JP6894866B2 - Power control system, power control device, and power control method - Google Patents

Description

The present disclosure relates to power control systems, power control devices, and power control methods.

For example, in a distributed power source such as photovoltaic power generation, if the power conversion operation is continued as it is in the event of a power failure of the system, the power output from the distributed power source may flow back to the system. If the power generated by the independent operation of such a distributed power source flows back to the system, there is a concern that the safety of humans and equipment may be affected. For this reason, among distributed power sources such as photovoltaic power generation, those that can supply power to the load by independent operation after disconnecting the system with a breaker or the like actively or passively detect independent operation and said the distributed power source. Measures will be taken to prevent independent operation, such as disconnecting the power from the system. For example, Patent Document 1 proposes a technique for detecting the independent operation of an inverter device connected to an electric power system.

JP-A-2007-318928

It would be extremely advantageous if the distributed power source with measures to prevent independent operation as described above could be adopted and the degree of utilization of the electric power generated by the distributed power source during independent operation could be increased.

The present disclosure relates to the provision of a power control system, a power control device, and a power control method that enhance the utilization of the power generated by the distributed power source during independent operation.

The electric power control system according to one embodiment is configured to be able to supply the electric power output from the first distributed power source and the second distributed power source to the load at the time of independent operation disconnected from the system.
The power control system includes a first power control device and a second power control device.
The first power control device controls the power output by the first distributed power source.
The first power control device has a function of self-sustaining operation output.
The second power control device controls the power output by the second distributed power source.
The second power control device has an independent operation prevention function for preventing the independent operation of the second distributed power source.
The first power control device has an independent operation prevention function of the second power control device based on the magnitude of the power supplied by the second distributed power source among the currents supplied to the load during self-sustaining operation. The magnitude of the electric power output by the first distributed power source is controlled so as not to operate.

The power control device according to the embodiment is a power control system capable of supplying power output from the first distributed power source and the second distributed power source to a load during independent operation disconnected from the system, and the first distributed power source outputs the power. Control the power to be generated.
The second power control device that controls the power output by the second distributed power source has an independent operation prevention function that prevents the independent operation of the second distributed power source.
The power control device has a function of self-sustaining operation output.
In the power control device, the independent operation prevention function of the second power control device does not operate based on the magnitude of the power supplied by the second distributed power source among the power supplied to the load during self-sustaining operation. As described above, the magnitude of the electric power output by the first distributed power source is controlled.

The power control method according to one embodiment is such that the first distributed power source outputs the power output from the first distributed power source and the second distributed power source to the load in a power control system capable of supplying the load with the power output by the first distributed power source and the second distributed power source during independent operation. Controls the amount of power generated.
In the power control method, the second power control device that controls the power output by the second distributed power source has an independent operation prevention function for preventing the independent operation of the second distributed power source.
In the power control method, the independent operation prevention function of the second power control device does not operate based on the magnitude of the power supplied by the second distributed power source among the power supplied to the load during self-sustaining operation. As described above, the magnitude of the electric power output by the first distributed power source is controlled.

According to one embodiment, it is possible to provide a power control system, a power control device, and a power control method that enhance the utilization of the power generated by the distributed power source during independent operation.

It is a figure which shows the example of the schematic structure and operation of the known power control system. It is a figure which shows the example of the schematic structure and operation of the known power control system. It is a figure which shows the example of the schematic structure and operation of the power control system which concerns on 1st Embodiment. It is a block diagram which shows the example of the schematic structure of the electric power control device which concerns on 1st Embodiment. It is a figure which shows the example of the schematic structure and operation of the power control system which concerns on 1st Embodiment. It is a flowchart which shows the example of the operation of the power control device which concerns on 1st Embodiment. It is a figure explaining the example of the operation of the electric power control apparatus which concerns on 1st Embodiment. It is a flowchart which shows the example of the operation of the power control apparatus which concerns on 2nd Embodiment. It is a flowchart which shows the example of the operation of the power control device which concerns on 3rd Embodiment.

Hereinafter, in order to explain the power control system according to the embodiment, first, the operation of the known power control system will be described.

FIG. 1 is a block diagram showing a schematic configuration example of a known power control system. In the following disclosure, detailed description of conventionally known functional parts will be omitted as appropriate.

The power control system shown in FIG. 1 includes a first distributed power source 100, a second distributed power source 20, and a distribution board 40. The first distributed power source 100 includes a first power source 11 and a first power control device 120. The second distributed power source 20 includes a second power source 21 and a second power control device 22.

The first distributed power source 100 can be a non-renewable energy power source, and for example, a storage battery (denoted as BT in FIG. 1) may be used as the power source. Hereinafter, the first distributed power source 100 will be described as being a power storage device using a storage battery as a power source, such as the first power supply 11. Further, the second distributed power source 20 can be a renewable energy power source, and for example, a solar cell (denoted as PV in FIG. 1) may be used as the power source. Hereinafter, the second distributed power source 20 will be described as being a photovoltaic power generation device using a solar cell as a power source, such as the second power source 21.

As shown in FIG. 1, the electric power output by the first power source 11 is supplied to the first electric power control device 120. The first power control device 120 can be configured by a known power conditioner (inverter). The first power control device 120 boosts or lowers the voltage of the DC power output (discharged) from the storage battery, which is the first power source 11, and converts it into AC power. The electric power converted into alternating current in the first electric power control device 120 is supplied to the distribution board 40 via the interconnection relay 32 or the self-sustaining operation relay 34. The distribution board 40 is connected to the system 50 and the load 60.

The interconnection relay 32 and the self-sustaining operation relay 34 can be configured by an arbitrary changeover switch or the like. The interconnection relay 32 and the self-sustaining operation relay 34 are basically controlled so that one is open and the other is closed. That is, at the time of grid interconnection, the interconnection relay 32 is closed and the self-sustained operation relay 34 is opened (see FIG. 1). Further, during self-sustaining operation, the interconnection relay 32 is opened and the self-sustaining operation relay 34 is closed (see FIG. 2). Such control may be performed by the first power control device 120, or may be performed by another control unit or control device.

The distribution board 40 includes a load 60 and a main breaker 31 that disconnects the system 50 from the first distributed power source 100 and the second distributed power source 20. The self-sustaining operation of the first distributed power source 100 is performed when the system 50 is disconnected by the main breaker 31. In recent years, some distribution boards 40 are provided with a power failure detection function to automatically disconnect the main breaker 31. In this example, the distribution board 40 includes a switching relay 42 that switches between interconnection operation and independent operation by a command transmitted by the first distributed power source 100. As a result, even if the main breaker 31 is not automatically disconnected, the output of the self-sustaining operation of the first distributed power source 100 can be supplied to the load 60.

As shown in FIG. 1, the power transmission line connecting the interconnection relay 32 and the switching relay 42 is referred to as a power transmission line PL1. The power transmission line PL1 is further connected to the system 50. Further, the power transmission line connecting the self-sustaining operation relay 34 and the switching relay 42 is referred to as a power transmission line PL2. Further, the power transmission line connecting the switching relay 42 and the load 60 is referred to as a power transmission line PL3. The switching relay 42 connects the power transmission line PL1 and the power transmission line PL3 during the interconnection operation (see FIG. 1). Further, the switching relay 42 connects the power transmission line PL2 and the power transmission line PL3 during self-sustaining operation (see FIG. 2). Such control of the switching relay 42 may also be performed by the first power control device 120, or may be performed by another control unit or control device.

The system 50 can be a general commercial power system (grid).

The load 60 can be various devices such as home appliances used by the user to which power is supplied from the power control system. In FIG. 1, the load 60 is shown as one configuration, but the load 60 is not limited to one configuration, and any number of various devices can be used. Further, the load 60 may be an outlet for indoor wiring.

Further, the first power control device 120 may be a bidirectional inverter. In this case, the first power control device 120 converts, for example, the AC power supplied from the system 50 into DC, boosts or lowers the voltage of the DC power, and supplies (charges) the storage battery which is the first power source 11. You can also do it.

The electric power output from the second power source 21 is supplied to the second electric power control device 22. The second power control device 22 can also be configured with a known power conditioner (inverter). The second power control device 22 boosts or lowers the voltage of the DC power output from the second power source 21 and converts it into AC power. The AC power output from the second power control device 22 is connected to the power transmission line PL1.

The power control system shown in FIG. 1 shows a state during interconnection operation. That is, as described above, in FIG. 1, the interconnection relay 32 is closed, the self-sustaining operation relay 34 is opened, and the switching relay 42 connects the power transmission line PL1 and the power transmission line PL3. In such an operating state, at least one of the output of the first distributed power source 100 and the output of the second distributed power source 20 can be supplied to the load 60. Further, the load 60 may be supplied with electric power from the system 50. Further, the first distributed power source 100 can also charge the electric power supplied from at least one of the system 50 and the second distributed power source 20. Further, the electric power generated by the second distributed power source 20 can be sold to the system 50 depending on the situation. As described above, according to the power control system shown in FIG. 1, it is possible to control the power of a plurality of distributed power sources.

FIG. 2 is a block diagram showing a schematic configuration example of the power control system shown in FIG. 1 during independent operation.

The power control system shown in FIG. 1 goes into an operating state as shown in FIG. 2 when, for example, a power failure is detected. The power control system shown in FIG. 2 shows a state during independent operation. That is, as described above, in FIG. 2, the interconnection relay 32 is opened, the self-sustained operation relay 34 is closed, and the switching relay 42 connects the power transmission line PL2 and the power transmission line PL3.

More specifically, when a power failure is detected in the power control system shown in FIG. 1, the first power control device 120 opens the interconnection relay 32. Then, when the power transmission line PL2 and the power transmission line PL3 are connected by the switching relay 42 and the self-sustaining operation relay 34 is closed (see FIG. 2), the first distributed power source 100 starts the output of the self-sustaining operation. Power is supplied to the load 60. At this time, the switching relay 42 can be operated by obtaining electric power from the output of the independent operation of the first distributed power source 100. In the power control system shown in FIG. 1, the operation from the detection of the power failure to the operation of the switching relay 42 can be about 10 seconds. In such an operating state, even during a power failure, the electric power charged in the storage battery of the first distributed power source 100 can be supplied to the load 60 by the independent operation output.

Here, it is assumed that the first power control device 120 (or the first distributed power source 100) and the second power control device 22 (or the second distributed power source 20) do not have a function of communicating with each other. Further, the second power control device 22 shown in FIG. 2 is assumed to have an independent operation prevention function. Further, the second power control device 22 can independently detect a power failure of the system 50. Therefore, the second power control device 22 independently detects the power failure of the system 50, and the independent operation of the second distributed power source 20 is avoided by the independent operation prevention function. Therefore, the electric power generated by the second distributed power source 20 at the time of a power failure does not flow back to the system 50.

However, in the power control system shown in FIG. 2, the second distributed power source 20 is not connected to the load 60. Therefore, in the operating state shown in FIG. 2, even if the second distributed power source 20 is in a state where it can generate power, the power output by the second distributed power source 20 cannot be supplied to the load 60. In this case, if the second power control device 22 is provided with a dedicated outlet capable of self-sustaining operation output, the power generated by the solar cell, which is the second power source 21, can be supplied from the dedicated outlet. However, the power output by the second distributed power source 20 cannot be supplied to the load 60 as it is.

Therefore, in the power control system according to the embodiment, the connection mode of the second distributed power source 20 is changed. Further, in the power control system according to the embodiment, the configuration of the first power control device 120 is changed.

(First Embodiment)
Hereinafter, the power control system according to the first embodiment will be described. FIG. 3 is a block diagram showing a schematic configuration example of the power control system according to the first embodiment.

As shown in FIG. 3, the power control system 1 according to the first embodiment changes the configuration of the first power control device 120 in the known power control system shown in FIG. As shown in FIG. 3, the power control system 1 according to the first embodiment includes a first power control device 12 instead of the first power control device 120 shown in FIG. As described above, in one embodiment, the power control system 1 includes a first distributed power source 10 and a second distributed power source 20. The first distributed power source 10 includes a first power source 11 and a first power control device 12. The second distributed power source 20 includes a second power source 21 and a second power control device 22. Here, the first power control device 12 controls the power output by the first power supply 11. Further, the second power control device 22 controls the power output by the second power supply 21.

Further, in the power control system shown in FIG. 1, the second distributed power source 20 was connected to the power transmission line PL1. On the other hand, as shown in FIG. 3, in the power control system 1 according to the first embodiment, the second distributed power source 20 is connected to the power transmission line PL3.

Further, as shown in FIG. 3, in the power control system 1 according to the first embodiment, the first current detection unit CT1 for detecting the current flowing from the first power control device 12 to the power transmission line PL2 may be provided. Further, in the power control system 1 according to the first embodiment, a second current detection unit CT2 for detecting the current flowing through the load 60 via the power transmission line PL3 may be provided. The first current detection unit CT1 and the second current detection unit CT2 can be, for example, a current sensor such as a CT (Current Transformer). However, as the first current detection unit CT1 and the second current detection unit CT2, any element can be adopted as long as it is an element capable of detecting the current. Further, the first current detection unit CT1 and the second current detection unit CT2 may calculate the electric power based on the detected current and transmit the calculated electric power information to the first electric power control device 12. ..

Since the configuration other than the above can be the same as that of the power control system shown in FIG. 1, a more detailed description will be omitted. Further, in the following embodiments, the description and illustration of the main breaker will be omitted.

Next, the first power control device 12 included in the power control system 1 according to the first embodiment will be further described. FIG. 4 is a block diagram showing a schematic configuration example of the power control system according to the first embodiment.

As shown in FIG. 4, the first power control device 12 includes a DC / DC converter 13, a DC / AC inverter 14, a control unit 15, and a storage unit 16. The first power control device 12 is, for example, a power conditioner.

The DC / DC converter 13 boosts or lowers the voltage of the DC power supplied from the first power supply 11. The DC power whose voltage is boosted or stepped down by the DC / DC converter 13 is supplied to the DC / AC inverter 14. The DC / DC converter 13 can be configured by using a known one.

The DC / AC inverter 14 converts the DC power supplied from the DC / DC converter 13 into AC power. The AC power converted by the DC / AC inverter 14 is supplied to the load 60 (omitted in FIG. 4) via the interconnection relay 32 and the power transmission line PL1 and the distribution board 40 during the interconnection operation. To. Further, the AC power converted by the DC / AC inverter 14 passes through the self-sustaining operation relay 34 and the power transmission line PL2 to the load 60 (omitted in FIG. 4) via the distribution board 40 at the time of self-sustaining operation output. Be supplied.

When the first power source 11 is a storage battery, the electric power supplied from the system 50 via the distribution board can be charged. In this case, the DC / AC inverter 14 converts the AC power supplied from the system 50 into DC power. Then, the DC / DC converter 13 boosts or lowers the voltage of the DC power supplied from the DC / AC inverter 14 and supplies it to the first power supply 11 which is a storage battery. The first power source 11 can charge the DC power supplied in this way.

The control unit 15 controls and manages the entire first power control device 12, including each functional unit constituting the first power control device 12. The control unit 15 can be configured to include, for example, a CPU (Central Processing Unit). The operation of the control unit 15 according to the first embodiment will be further described later.

The first power control device 12 may include at least one processor as the control unit 15 in order to provide control and processing power for performing various functions. According to various embodiments, at least one processor may be implemented as a single integrated circuit (IC) or as multiple communicable integrated circuits and / or discrete circuits. Good. At least one processor can be implemented according to various known techniques.

In one embodiment, the processor comprises one or more circuits or units configured to perform one or more data computation procedures or processes. For example, the processor may be one or more processors, controllers, microprocessors, microcontrollers, application specific integrated circuits (ASICs), digital signal processing devices, programmable logic devices, field programmable gate arrays, or any of these devices or configurations. The functions described below may be performed by including combinations or combinations of other known devices or configurations.

The storage unit 16 may be composed of a semiconductor memory, a magnetic memory, or the like. The storage unit 16 stores various information and programs executed by the control unit 15. The storage unit 16 may function as a work memory of the control unit 15. Further, the storage unit 16 may be included in the control unit 15.

As shown in FIG. 4, the first current detection unit CT1 detects the current flowing from the DC / AC inverter 14 of the first power control device 12 to the power transmission line PL2. The result detected by the first current detection unit CT1 is transmitted to the control unit 15 and multiplied by the output side voltage of the DC / AC inverter 14 to calculate the power value. Further, as shown in FIG. 3, the second current detection unit CT2 detects the current flowing through the power transmission line PL3 and the load 60. The result detected by the second current detection unit CT2 is also transmitted to the control unit 15 and multiplied by the output side voltage of the DC / AC inverter 14 to calculate the power value. In this example, the subsequent control in the control unit 15 is performed based on the calculated power value. In one embodiment, the power value may be calculated based on the current detected by a current detection unit such as the first current detection unit CT1 and / or the second current detection unit CT2. Further, the electric power value may be obtained by a wattmeter that uniquely measures the electric power.

The control unit 15 may control the switching of the switching relay 42 on the distribution board 40. Further, the control unit 15 may control switching between the interconnection relay 32 and / or the self-sustaining operation relay 34.

The power control system 1 shown in FIG. 3 shows a state during interconnection operation. That is, in FIG. 3, the interconnection relay 32 is closed, the self-sustained operation relay 34 is opened, and the switching relay 42 connects the power transmission line PL1 and the power transmission line PL3. In such an operating state, at least one of the output of the first distributed power source 10 and the output of the second distributed power source 20 can be supplied to the load 60. Further, the load 60 may be supplied with electric power from the system 50. Further, the storage battery which is the first power source 11 can also charge the electric power supplied from at least one of the system 50 and the second distributed power source 20. Further, the electric power generated by the photovoltaic power generation device, which is the second distributed power source 20, can be sold to the system 50 depending on the situation. As described above, according to the power control system 1 shown in FIG. 3, the power of a plurality of distributed power sources can be controlled in the same manner as the power control shown in FIG. 1 during the interconnection operation.

FIG. 5 is a block diagram showing a schematic configuration example of the power control system 1 shown in FIG. 3 during independent operation.

When the power control system 1 shown in FIG. 3 detects, for example, a power failure, the power control system 1 enters the operating state as shown in FIG. The power control system shown in FIG. 5 shows a state during independent operation. That is, in FIG. 5, after the first power control device 12 and the second power control device 22 detect a power failure and stop the output, the interconnection relay 32 is opened and the self-sustaining operation relay 34 is closed. The switching relay 42 connects the power transmission line PL2 and the power transmission line PL3.

Here, the first power control device 12 and the second power control device 22 may not have a function of communicating with each other. Further, the second power control device 22 shown in FIG. 5 shall have an independent operation prevention function. Further, the second power control device 22 can independently detect a power failure of the system 50.

As shown in FIG. 5, the second distributed power source 20 is connected to the load 60 even during independent operation. Therefore, in the operating state shown in FIG. 5, if the solar cell as the second power source 21 can generate electricity, the power output by the second distributed power source 20 can be supplied to the load 60. As described above, in one embodiment, the power control system 1 outputs the power output by the first power source 11 (for example, a storage battery) and the second power source 21 (for example, a solar cell) during the self-sustained operation disconnected from the system 50. It is configured to be able to supply the load 60.

On the other hand, as described above, the second power control device 22 has an independent operation prevention function, and can independently detect a power failure of the system 50. That is, in one embodiment, the second power control device 22 has an independent operation prevention function for preventing the independent operation of the second distributed power source 20. Therefore, when the second power control device 22 independently detects a power failure in the system 50, the output of the second distributed power source 20 is stopped by the independent operation prevention function. In such a case, the power generated by the solar cell, which is the second power source 21, cannot be supplied to the load 60 at the time of a power failure.

More specifically, in the operating state shown in FIG. 5, the first power control device 12 switches the control to the self-sustaining operation mode, and outputs the AC output from the first power control device 12 based on the output of the first power supply 11 which is a storage battery. Start. In the self-sustaining operation mode, the independent operation prevention function is not detected, so that the first power control device 12 continues the output. Using the AC output of the first power control device 12 as a reference waveform, the second power control device 22 of the second distributed power source 20 starts the output. However, the second power control device 22 determines that the reference waveform is due to a power source other than the system 50 by the active detection of the independent operation prevention function. In this case, the second power control device 22 determines that the system 50 is out of power and stops the output of the second power control device 22.

In this way, even if the second distributed power source 20 is connected to the power transmission line PL3 so that the generated power can be supplied to the load 60, the power output by the second distributed power source 20 can be transmitted to the power transmission line PL3 in the event of a power failure. It is also assumed that the load 60 cannot be supplied after that. In particular, when the second power control device 22 cannot acquire the information that the second power control device 22 is in the self-sustaining operation state from the first power control device 12 or the distribution board 40 or the like, the output of the second power supply 21 cannot be supplied to the load 60 in the event of a power failure. Is expected. Further, even when the second power control device 22 is a device that cannot disable the independent operation prevention function (there is no function to stop the active detection), the output of the second power supply 21 cannot be supplied to the load 60 in the event of a power failure. Further, in such a case, there may be a problem that the chattering operation in which the second power control device 22 temporarily outputs the generated power of the second power source 21 and then stops is repeated.

Further, in recent years, it has been desired to supply electric power to the power transmission line PL3 side so that the output of independent operation can be supplied to, for example, a household outlet even in the event of a power failure. However, in the event of a power outage, since the capacity of non-renewable energy power sources such as storage batteries is limited, it may be difficult to continue to cover the load only with the output of the storage batteries. Therefore, if the degree of utilization of the generated power of a renewable energy power source such as a solar cell can be increased according to the output of the storage battery, the superiority of the power control system can be enhanced.

Therefore, in the first embodiment, the first power control device 12 controls so that the independent operation prevention function of the second power control device 22 does not operate during the self-sustaining operation. Hereinafter, the operation of the first power control device 12 according to the first embodiment will be further described.

Here, the independent operation prevention function of the second power control device 22 is a function installed for reasons such as safety. Therefore, in the following description, it is assumed that the second distributed power source 20 is disconnected from the system 50 when the independent operation prevention function of the second power control device 22 is controlled so as not to operate during the independent operation.

FIG. 6 is a flowchart illustrating the operation of the first power control device 12 according to the first embodiment.

In the following description, the power output from the first power source 11 and the power supplied to the load 60 by the first power control device 12 is abbreviated as “output of the first distributed power source 10”. The current value of the output of the first distributed power source 10 can be detected by the first current detection unit CT1. Similarly, the power output from the second power source 21 and the power supplied to the load 60 by the second power control device 22 is abbreviated as “output of the second distributed power source 20”. The current value of the output of the second distributed power source 20 can be calculated by subtracting the value detected by the first current detection unit CT1 from the value detected by the second current detection unit CT2. Each current value is converted into power value or power waveform information in the first power control device 12 and used for control.

The operation shown in FIG. 6 may start at a time when power is no longer supplied from the system 50 to the power control system 1 due to, for example, a power failure of the system 50. Further, the operation shown in FIG. 6 starts when the operation of the power control system 1 is temporarily stopped due to, for example, a power failure of the system 50, and then the power output from the first power supply 11 by the first power control device 12. It may be the time to resume the supply of. Here, when the operation of the power control system 1 is temporarily stopped, the first power control device 12 stops the supply of the power output from the first power supply 11, and the second power control device 22 further stops the supply of the power. The supply of electric power output from the power source 21 may be stopped.

When the operation shown in FIG. 6 starts, the control unit 15 of the first power control device 12 invalidates the independent operation prevention function of the own machine, that is, the first power control device 12 (step S11). As described above, the first power control device 12 according to the first embodiment can invalidate the independent operation prevention function of its own device, that is, the first power control device 12 by the control of the control unit 15. On the other hand, the first power control device 12 and the second power control device 22 do not have a function of communicating with each other. Therefore, the first power control device 12 (control unit 15) cannot perform control that invalidates the independent operation prevention function of the second power control device 22.

After disabling the independent operation prevention function in step S11, the control unit 15 controls the first power control device 12 so as to start the output (discharge) of the first power supply 11 (step S12). In step S12, it is assumed that the output of the second distributed power source 20 has not been started yet.

When the output of the first distributed power source 10 (in other words, the output of the first power control device 12) is started in step S12, the control unit 15 performs the process of step S13. In step S13, the control unit 15 determines the ratio of the output of the first distributed power source 10 to the output of the second distributed power source 20 (in other words, the output of the second power control device 22) (hereinafter, referred to as “predetermined ratio”). Is read from the storage unit 16. Hereinafter, the predetermined ratio is 200% as an example. It is assumed that the storage unit 16 stores that the predetermined ratio is 200%. Then, in step S13, the control unit 15 calculates the output of the first distributed power source 10 which is equal to or more than a predetermined ratio with respect to the output of the second distributed power source 20.

Hereinafter, the above-mentioned example will be further described. FIG. 7 is a diagram illustrating an example of step S13. In FIG. 7, the power value of the output of the first distributed power source 10 is 200% or more of the power value of the output of the second distributed power source 20.

FIG. 7 shows the power value supplied to the load 60, the power value of the output of the second distributed power source 20, and the power value of the output of the first distributed power source 10 in order from the left column to the right column. There is. In step S13, the control unit 15 may calculate the power value of the output of the first distributed power source 10 based on the power value of the output of the second distributed power source 20.

As shown in FIG. 7, when the power value of the output of the second distributed power source 20 is 500 [W], the control unit 15 may set the power value of the output of the first distributed power source 10 to 1000 [W] or more. .. That is, the power value of the output of the first distributed power source 10 is set to be 200% or more of the power value of the output of the second distributed power source 20. In this case, the power supplied to the load 60 is 1500 [W]. When the power value of the output of the second distributed power source 20 is 300 [W], the control unit 15 may set the power value of the output of the first distributed power source 10 to 600 [W] or more. In the example of FIG. 7, the power value of the output of the first distributed power source 10 is 700 [W], and in this case, the power supplied to the load 60 is 1000 [W]. When the power value of the output of the second distributed power source 20 is 150 [W], the control unit 15 may set the power value of the output of the first distributed power source 10 to 300 [W] or more. In the example of FIG. 7, the power value of the output of the first distributed power source 10 is 350 [W], and in this case, the power supplied to the load 60 is 500 [W]. When the power value of the output of the second distributed power source 20 is 100 [W], the control unit 15 may set the power value of the output of the first distributed power source 10 to 200 [W] or more. In this case, the power supplied to the load 60 is 300 [W].

In the above-described embodiment, the predetermined ratio is assumed to be 200%. However, in one embodiment, the predetermined percentage is not limited to 200%. For example, the predetermined ratio may be appropriately increased or decreased within a range in which the independent operation prevention function of the second power control device 22 connected to the second power source 21 (solar cell) does not detect a power failure by active detection. The predetermined ratio is determined by grasping in advance the power value capable of disabling the AC waveform of the ineffective power generated when the independent operation prevention function of the second power control device 22 actively detects the independent operation. Can be done. In the above example, if the output of the first distributed power source 10 is 200% or more of the output of the second distributed power source 20, the second power control device 22 of the second distributed power source 20 does not operate the independent operation prevention function. It was explained as.

After the processing of step S13 is performed, the control unit 15 controls so as to reduce the output of the first distributed power source 10 toward the output of the ratio calculated in step S13 (step S14). In step S14, the control unit 15 controls the first power control device 12 so that the output of the first distributed power source 10 is reduced. In step S14, the control unit 15 may control the power output from the first distributed power source 10 by the power value.

In step S14, the control unit 15 reduces the output of the first distributed power source 10 toward the output of the ratio calculated in step S13. At this time, when the output of the first distributed power source 10 is reduced, the control unit 15 controls so as not to fall below the output of the ratio calculated in step S13. This is because when the output of the first distributed power source 10 is less than the output of the ratio calculated in step S13, the independent operation prevention function of the second power control device 22 of the second distributed power source 20 can be activated.

Further, in step S14, the control unit 15 may gradually reduce the output of the first distributed power source 10 without sharply reducing it. If the output of the first distributed power source 10 suddenly decreases in step S14, the power consumption of the load 60 becomes insufficient and the voltage drops. Therefore, the overload protection function of the first power control device 12 of the first distributed power source 10 is activated. There is a possibility that it will operate and the output will be stopped in an emergency. Therefore, in one embodiment, the control unit 15 may gradually reduce the output of the first distributed power source 10 by a loop based on step S16 described later. For example, in step S14, the output of the first distributed power source 10 may be gradually reduced so that the load devices constituting the load 60 do not stop. The amount of reduction in this case may be, for example, several tens of watts. Further, the loop for reducing the output may be repeated every second, for example.

When the output of the first distributed power source 10 is reduced in step S14, the control unit 15 acquires the output of the second distributed power source 20 (step S15). In step S15, the control unit 15 subtracts the current value (power value) detected by the first current detection unit CT1 from the current value (power value) detected by the second current detection unit CT2, thereby causing the second distributed power source. The power value of 20 outputs can be obtained.

When the output of the second distributed power source 20 is acquired in step S15, the control unit 15 determines whether or not the increase in the output of the second distributed power source 20 is smaller than the decrease in the output of the first distributed power source 10. (Step S16).

If the determination in step S16 is denied (No), the control unit 15 returns to step S14 and continues the process. The determination in step S16 is denied when the increase in the output of the second distributed power source 20 is equal to or greater than the decrease in the output of the first distributed power source 10. In this case, even if the output of the first distributed power source 10 is reduced, the decrease can be compensated for by the output of the second distributed power source 20. Therefore, in this case, assuming that the output of the second distributed power source 20 still has a margin, the output of the first distributed power source 10 is reduced. Therefore, the control unit 15 returns to step S14 and further reduces the output of the first distributed power source 10 toward the output of the ratio calculated in step S13.

On the other hand, if the determination in step S16 is affirmative (Yes), the control unit 15 increases the output of the first distributed power source 10 (step S17). The determination in step S16 is affirmed when the increase in the output of the second distributed power source 20 is smaller than the decrease in the output of the first distributed power source 10. The determination in step S16 is affirmed because, for example, the output of the second distributed power source 20 is not sufficient due to insufficient solar radiation. Further, the determination in step S16 may be affirmed when, for example, the power consumption of the load 60 increases. In such a case, the decrease in the output of the first distributed power source 10 cannot be compensated for by the output of the second distributed power source 20, that is, the output of the second distributed power source 20 is insufficient. Therefore, in this case, the shortage of the output of the second distributed power source 20 may be compensated by increasing the output of the first distributed power source 10.

In step S17, the control unit 15 may increase the output of the first distributed power source 10 by returning it to a predetermined initial value or the like. Further, the control unit 15 may store, for example, the output before reducing the output of the first distributed power source 10 in the storage unit 16 in step S14. In this case, when the output of the first distributed power source 10 is increased in step S17, the control unit 15 may increase the output of the first distributed power source 10 so as to return to the output before the decrease in step S14.

The procedure for the control unit 15 to perform the operation as described above may be stored in the storage unit 16 as a program in advance.

As described above, the first power control device 12 (in other words, the first distributed power source 10 including the first power source 11) according to the first embodiment is the second power control device 22 (in other words, the second power control device 22) during self-sustaining operation. The independent operation prevention function of the second distributed power source 20) including the power source 21 is controlled so as not to operate. In this case, the first power control device 12 according to the first embodiment outputs the first distributed power source 10 based on the magnitude of the power supplied by the second distributed power source 20 among the power supplied to the load 60. Controls the amount of power generated.

Here, the power output by the first distributed power source 10 is defined as the first power. Further, the power obtained by subtracting the first power from the power calculated from the current detected by the second current detection unit CT2 is defined as the second power. As described above, in the first electric power control device 12 according to the first embodiment, the control unit 15 outputs the first distributed power source 10 so that the ratio of the first electric power to the second electric power becomes equal to or more than a predetermined value. You may control the power.

According to the first power control device 12 according to the first embodiment, the output of the distributed power source is the output of the self-sustaining operation of the power storage device without activating the independent operation prevention function of the distributed power source such as the photovoltaic power generation device. The load 60 can be continuously supplied according to the above. Therefore, according to the first power control device 12 according to the first embodiment, it is possible to increase the degree of utilization of the generated power of a renewable energy power source such as a photovoltaic power generation device in accordance with the output of the power storage device. Therefore, the first power control device 12 according to the first embodiment can enhance the superiority of the power control system.

Further, the first power control device 12 according to the first embodiment controls the output of the first power control device 12 by the ratio with the output of the second power control device 22 even if the power consumption of the load 60 increases or decreases. To do. Therefore, according to the first power control device 12 according to the first embodiment, it is possible to prevent the output from being biased toward the second distributed power source side, which is, for example, a solar power generation device.

(Second Embodiment)
Next, the power control system according to the second embodiment will be described.

The power control system according to the second embodiment can be realized by the same configuration as the power control system 1 according to the first embodiment described with reference to FIGS. 3 to 5. The power control system according to the second embodiment can be configured in the same manner as the power control system 1 according to the first embodiment described with reference to FIGS. 3 to 5, but with the power control system 1 according to the first embodiment. Performs some different controls. Hereinafter, the same description as that of the power control system 1 according to the first embodiment described with reference to FIGS. 3 to 5 will be simplified or omitted as appropriate.

As described above, the second power control device 22 of the second distributed power source 20 operates the independent operation prevention function by detecting the invalid power output by the own machine. Therefore, in the second embodiment, the first power control device 12 of the first distributed power source 10 has an output having a size capable of preventing the waveform (power or voltage phase) of the reactive power from being detected by the second power control device 22. The power value is determined based on the flowchart of FIG. However, in reality, the detection of the waveform of the invalid power of the second power control device 22 is generally provided with an allowable range, and the power at which the second power control device 22 does not operate the independent operation prevention function. Up to the value, the output can be increased. That is, although the first power control device 12 detects the invalid power waveform, the second power is up to the "upper limit value" defined as a preset upper limit value (hereinafter, simply referred to as "upper limit value"). The control device 22 is controlled so as not to operate the independent operation prevention function. Here, the first power control device 12 may determine the upper limit value without exchanging information with the second power control device 22. The upper limit value may be determined by, for example, the manufacturer of the first power control device 12 by actual measurement, and then stored in the storage unit 16 at the manufacturing stage, for example.

Next, in the second embodiment, the first power control device 12 of the first distributed power source 10 sets the "set value" of the disabled power as the value of the disabled power equal to or less than the above-mentioned "upper limit value". Since the invalid power up to this "set value" is the invalid power equal to or less than the above-mentioned upper limit value, the second power control device 22 does not operate the independent operation prevention function.

The above-mentioned "upper limit value" is a fixed value regardless of the output of the second distributed power source 20. On the other hand, in the second embodiment, the above-mentioned "set value" may be changed according to the output of the second distributed power source 20. When the output of the second distributed power source 20 is small, it is assumed that the output of the second power source 21 (solar cell) suddenly increases (suddenly recovers to the output that can originally generate power) due to, for example, a sudden change in solar radiation. In such a case, the ineffective power of the second power control device 22 connected to the second power source 21 (solar cell) can increase rapidly. Then, the first power control device 12 of the first distributed power source 10 may not complete the control for increasing the output in time, and the second power control device 22 may operate the independent operation prevention function.

Therefore, the first power control device 12 according to the second embodiment may set the above-mentioned set value in order to cope with the above-mentioned sudden change in the ineffective power. For example, the first power control device 12 according to the second embodiment may set a set value lower than the upper limit value as the output of the second distributed power source 20 is smaller. If the set value is set low, even if the output of the second power source 21 (solar cell) changes rapidly from a small state to a large value, the power margin until the upper limit is reached is increased, so that the first power control device 12 The risk is low because there is time to increase the output. Therefore, the risk that the second power control device 22 operates the independent operation prevention function is low.

As a specific example, the first power control device 12 may set the set value to 7 W when the output of the second distributed power source 20 is, for example, 3 kW. This set value may be an allowable value of invalid power suitable for the value of the output power determined based on the flowchart of FIG. Further, the first power control device 12 may set the set value to 12 W, for example, when the output of the second distributed power source 20 is 5 kW. Further, the first power control device 12 may set the set value to 25 W, for example, when the output of the second distributed power source 20 is 10 kW.

In the above example, the set value of the reactive power is set in the unit of [W]. However, in the second embodiment, the set value of the reactive power may be set as the reactive power according to the magnitude of the output of the second distributed power source 20 by using the phase shift width with respect to the ideal waveform.

As a specific example, the first power control device 12 may set the set value to 0.5 Hz, for example, when the output of the second distributed power source 20 is 1 kW. Further, the first power control device 12 may set the set value to 0.7 Hz, for example, when the output of the second distributed power source 20 is 3 kW. Further, the first power control device 12 may set the set value to 1.0 Hz, for example, when the output of the second distributed power source 20 is 5 kW.

FIG. 8 is a flowchart illustrating the operation of the first power control device 12 according to the second embodiment. Hereinafter, the operation of the first power control device 12 according to the second embodiment will be described. The premise of the operation shown in FIG. 8 can be the same as that of the first embodiment described in FIG.

The processing of steps S21 to S25 shown in FIG. 8 can be the same as the processing of steps S11 to S15 shown in FIG. Therefore, the description of steps S21 to S25 will be omitted.

When the output of the second distributed power source 20 is acquired in step S25, the control unit 15 determines whether or not the output of the second distributed power source 20 is increasing (step S26). In step S26, the control unit 15 may determine, for example, whether or not the output of the second distributed power source 20, which is constantly monitored, has increased by a predetermined amount or more in a predetermined time. Further, in step S26, the control unit 15 obtains, for example, the output of the second distributed power source 20 acquired when the operation shown in FIG. 8 was performed last time and the output of the second distributed power source 20 acquired this time. By comparison, it may be determined whether or not the increase has occurred.

If the determination in step S26 is affirmed (Yes), the control unit 15 sets the above-mentioned set value of the disabled power (step S27). In step S27, as described above, the control unit 15 may set a set value lower than the upper limit value as the output of the second distributed power source 20 is smaller.

When the set value is set in step S27, the control unit 15 determines whether or not the output of the second distributed power source 20 has reached the set value (step S28).

If the determination in step S28 is denied (No), the control unit 15 returns to step S24 and continues the process. If the determination in step S28 is denied, the output of the first distributed power source 10 is reduced, assuming that the output of the second distributed power source 20 still has a margin. Therefore, the control unit 15 returns to step S24 and further reduces the output of the first distributed power source 10 toward the output of the ratio calculated in step S23.

On the other hand, if the determination in step S28 is affirmative (Yes), the control unit 15 increases the output of the first distributed power source 10 (step S29). If the determination in step S28 is affirmed, it is assumed that if the output of the first distributed power source 10 is further reduced, the risk of operating the independent operation prevention function of the second power control device 22 increases. Therefore, in this case, the control unit 15 increases the output of the first distributed power source 10.

In step S29, the control unit 15 may increase the output of the first distributed power source 10 by returning it to a predetermined initial value or the like. Further, the control unit 15 may store, for example, the output before reducing the output of the first distributed power source 10 in the storage unit 16 in step S24. In this case, when the output of the first distributed power source 10 is increased in step S29, the control unit 15 may increase the output of the first distributed power source 10 so as to return to the output before the decrease in step S24.

If the determination in step S26 is denied (No), the control unit 15 proceeds to step S29 to increase the output of the first distributed power source 10 (step S29). The case where the determination in step S26 is denied corresponds to the case where the output of the second distributed power source 20 is not increased. In this case, the power component whose output is reduced by the first distributed power source 10 in step 24 is not supplemented by the output of the second distributed power source 20, and when the output of the first distributed power source 10 is further reduced, the second It is assumed that the risk of operating the independent operation prevention function of the power control device 22 increases. Further, in this case, since there is not enough power to be supplied to the load, it is expected that the risk of the overload protection function operating when the load power consumption increases also increases. Therefore, in this case, the control unit 15 increases the output of the first distributed power source 10 in step S29.

As described above, the first power control device 12 according to the second embodiment has an invalid value equal to or less than the upper limit value based on the upper limit value of the invalid power in which the independent operation prevention function of the second power control device 22 does not operate. You may set the power setting value. Further, the first power control device 12 according to the second embodiment has a first distributed power source 10 so that the power supplied by the second distributed power source 20 among the power supplied to the load 60 does not exceed the set value. You may control the power output by. Further, the first power control device 12 according to the second embodiment may set the set value according to the power supplied by the second distributed power source 20 among the currents supplied to the load 60. Further, the first power control device 12 according to the second embodiment outputs the first distributed power source 10 when the power supplied by the second distributed power source 20 among the currents supplied to the load 60 reaches the set value. You may increase the power generated. Further, the first power control device 12 according to the second embodiment outputs the first distributed power source 10 until the power supplied by the second distributed power source 20 among the currents supplied to the load 60 reaches the set value. You may reduce the power generated.

According to the first power control device 12 according to the second embodiment, the output of the distributed power source is the output of the self-sustaining operation of the power storage device without activating the independent operation prevention function of the distributed power source such as the photovoltaic power generation device. The load 60 can be continuously supplied according to the above. Therefore, according to the first power control device 12 according to the second embodiment, it is possible to increase the degree of utilization of the generated power of a renewable energy power source such as a photovoltaic power generation device in accordance with the output of the power storage device. Therefore, the first power control device 12 according to the second embodiment can enhance the superiority of the power control system. Further, according to the first power control device 12 according to the second embodiment, even if the output of the second distributed power source 20 changes rapidly from a small state to a large value due to, for example, a sudden change in solar radiation, the second power control device 22 Reduces the risk of activating the stand-alone operation prevention function.

(Third Embodiment)
Next, the power control system according to the third embodiment will be described.

The power control system according to the third embodiment modifies a part of the control in the power control system according to the second embodiment described above. Hereinafter, the same description as that of the power control system according to the first embodiment or the second embodiment described with reference to FIGS. 3 to 8 will be simplified or omitted as appropriate.

In the power control system according to the second embodiment described above, the first power control device 12 sets a set value of the invalid power according to the output of the second distributed power source 20. In particular, in the second embodiment, the smaller the output of the second distributed power source 20, the lower the set value than the upper limit value is set.

On the other hand, in the power control system according to the third embodiment, the first power control device 12 sets a set value in advance regardless of the output of the second distributed power source 20. In particular, in the third embodiment, an arbitrary set value may be set as the value of the invalid power equal to or less than the above-mentioned upper limit value. For example, in the third embodiment, a value lower than the above-mentioned upper limit value by a predetermined value may be set as a set value. In this case, for example, a value slightly lower than the above-mentioned upper limit value may be set as the set value. This specified value may be specified by, for example, the manufacturer of the first power control device 12 by actual measurement, and then stored in the storage unit 16 at the manufacturing stage, for example. Further, this specified value may be set, for example, during the operation of the first power control device 12 and before the second power control device 22 starts the output of the second distributed power source 20.

FIG. 9 is a flowchart illustrating the operation of the first power control device 12 according to the third embodiment. Hereinafter, the operation of the first power control device 12 according to the third embodiment will be described. The premise of the operation shown in FIG. 9 can be the same as that of the first embodiment or the second embodiment described with reference to FIG. 6 or 8.

The processing of steps S31 to S36 shown in FIG. 9 can be the same as the processing of steps S21 to S26 shown in FIG. Therefore, the description of steps S31 to S36 will be omitted.

If the determination in step S36 is affirmative (Yes), the control unit 15 determines whether or not the output of the second distributed power source 20 has reached the set value (step S37).

If the determination in step S37 is denied (No), the control unit 15 returns to step S34 and continues the process. If the determination in step S37 is denied, the output of the first distributed power source 10 is reduced, assuming that the output of the second distributed power source 20 still has a margin. Therefore, the control unit 15 returns to step S34 and further reduces the output of the first distributed power source 10 toward the output of the ratio calculated in step S33.

On the other hand, when the determination in step S37 is affirmed (Yes), the control unit 15 increases the output of the first distributed power source 10 (step S38). If the determination in step S37 is affirmed, it is assumed that if the output of the first distributed power source 10 is further reduced, the risk of operating the independent operation prevention function of the second power control device 22 increases. Therefore, in this case, the control unit 15 increases the output of the first distributed power source 10.

In step S38, the control unit 15 can perform the same processing as in step S29 in the second embodiment shown in FIG.

If the determination in step S36 is denied (No), the control unit 15 proceeds to step S38 to increase the output of the first distributed power source 10 (step S38). The case where the determination in step S36 is denied corresponds to the case where the output of the second distributed power source 20 is not increased. In this case, the power component whose output is reduced by the first distributed power source 10 in step 34 is not supplemented by the output of the second distributed power source 20, and when the output of the first distributed power source 10 is further reduced, the second It is assumed that the risk of operating the independent operation prevention function of the power control device 22 increases. Further, in this case, since there is not enough power to be supplied to the load, it is expected that the risk of the overload protection function operating when the load power consumption increases also increases. Therefore, in this case, the control unit 15 increases the output of the first distributed power source 10 in step S38.

As described above, the first power control device 12 according to the second embodiment has an invalid value equal to or less than the upper limit value based on the upper limit value of the invalid power in which the independent operation prevention function of the second power control device 22 does not operate. You may set the power setting value. Further, the first power control device 12 according to the second embodiment has a first distributed power source 10 so that the power supplied by the second distributed power source 20 among the power supplied to the load 60 does not exceed the set value. You may control the power output by. Further, the first power control device 12 according to the second embodiment outputs the first distributed power source 10 when the power supplied by the second distributed power source 20 among the power supplied to the load 60 reaches the set value. You may increase the power generated. Further, the first power control device 12 according to the second embodiment outputs the first distributed power source 10 until the power supplied by the second distributed power source 20 among the power supplied to the load 60 reaches the set value. You may reduce the power generated.

According to the first power control device 12 according to the third embodiment, similarly to the first embodiment and the second embodiment, the distributed power source such as the photovoltaic power generation device does not operate the independent operation prevention function. The output of the distributed power source can be continuously supplied to the load 60 in accordance with the output of the self-sustaining operation of the power storage device. Therefore, according to the first power control device 12 according to the third embodiment, it is possible to increase the degree of utilization of the generated power of a renewable energy power source such as a photovoltaic power generation device in accordance with the output of the power storage device. Further, according to the first power control device 12 according to the third embodiment, the operation according to the power control system according to the second embodiment is performed by simpler control than the first power control device 12 according to the second embodiment. It can be performed. Therefore, the first power control device 12 according to the third embodiment can enhance the superiority of the power control system.

Although the present disclosure has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications or modifications based on the present disclosure. It should be noted, therefore, that these modifications or modifications are within the scope of this disclosure. For example, the functions included in each functional unit can be rearranged so as not to be logically inconsistent. A plurality of functional parts and the like may be combined or divided into one. Each of the above-described embodiments according to the present disclosure is not limited to the implementation faithful to each of the embodiments described above, and may be implemented by combining the features or omitting a part thereof as appropriate. ..

In each of the above-described embodiments, the first distributed power source 10 has been described as being a power storage device. Further, in each of the above-described embodiments, the second distributed power source 20 has been described as being a photovoltaic power generation device. However, in one embodiment, the first distributed power source 10 is not limited to the power storage device, and the second distributed power source 20 is not limited to the photovoltaic power generation device. In one embodiment, the first distributed power source 10 can be various non-renewable energy power sources. Further, in one embodiment, the second distributed power source 20 can be various renewable energy power sources. For example, in one embodiment, the second distributed power source 20 is a fuel such as a solid oxide fuel cell (SOFC) or a polymer electrolyte fuel cell (PEFC). It may be a battery device. Further, for example, in one embodiment, when the first distributed power source 10 is a power storage device, the second distributed power source 20 may be another power storage device.

Further, the above-described embodiment is not limited to the implementation as the power control system 1. For example, the above-described embodiment may be implemented as a power control device such as the first power control device 12 included in the power control system 1. Further, for example, the above-described embodiment may be implemented as a power control method for a power control device such as the first power control device 12.

Further, the above-described embodiment is not limited to the embodiment as one first power control device or one second power control device. For example, two second power control devices may be connected to one first power control device. In this case, the first power control device may perform control based on the sum of the output powers of the plurality of second power control devices and the combined value of the ineffective power.

1 Power control system 10 1st distributed power supply 11 1st power supply 12 1st power control device 13 DC / DC converter 14 DC / AC inverter 15 Control unit 16 Storage unit 20 2nd distributed power supply 21 2nd power supply 22 2nd power control device 31 Main breaker 32 Interconnect relay 34 Independent operation relay 40 Distribution board 42 Switching relay 50 system 60 Load CT1 1st current detector CT2 2nd current detector PL1, PL2, PL3 Transmission line

Claims (10)

It is a power control system that can supply the power output from the first distributed power source and the second distributed power source to the load during independent operation that is disconnected from the grid.
A first power control device that controls the power output by the first distributed power source, and
A second power control device for controlling the power output by the second distributed power source is provided.
The first power control device has a function of self-sustaining operation output, and has a function of self-sustaining operation output.
The second power control device has an independent operation prevention function for preventing the independent operation of the second distributed power source.
The first power control device has an independent operation prevention function of the second power control device based on the magnitude of the power supplied by the second distributed power source among the power supplied to the load during self-sustaining operation. A power control system that controls the amount of power output by the first distributed power source so that it does not operate. The first distributed power source is a non-renewable energy power source.
The power control system according to claim 1, wherein the second distributed power source is a renewable energy power source. The first distributed power source is a storage battery.
The power control system according to claim 1 or 2, wherein the second distributed power source is a solar cell. A first current detection unit that detects the current output by the first distributed power source, and
A second current detection unit that detects a total current of the current output by the first distributed power source and the current output by the second distributed power source is provided.
The power value based on the current detected by the first current detection unit is defined as the first power, and the current value obtained by subtracting the current detected by the first current detection unit from the current detected by the second current detection unit is used. The power output by the first distributed power source is controlled so that the ratio of the first power to the second power is equal to or greater than a predetermined value, with the power value based on the second power as the second power.
The power control system according to any one of claims 1 to 3. The first power control device sets an invalid power setting value that is equal to or less than the upper limit value based on the upper limit value of the invalid power in which the independent operation prevention function of the second power control device does not operate.
The first power control device controls the power output by the first distributed power source so that the power supplied by the second distributed power source among the power supplied to the load does not exceed the set value.
The power control system according to any one of claims 1 to 3. The power control system according to claim 5, wherein the first power control device sets a plurality of the set values according to the power supplied by the second distributed power source among the power supplied to the load. The first power control device increases the power output by the first distributed power source when the ineffective power supplied by the second distributed power source among the power supplied to the load reaches the set value. Item 5. The power control system according to item 5 or 6. The first power control device reduces the power output by the first distributed power source until the invalid power supplied by the second distributed power source among the power supplied to the load reaches the set value. Item 6. The power control system according to Item 6. It is a power control device that controls the power output by the first distributed power source in a power control system capable of supplying the power output by the first distributed power source and the second distributed power source to the load during independent operation disconnected from the grid. hand,
The power control device has a function of independent operation output, and has a function of self-sustaining operation output.
The power control device controls the power output by the second distributed power source based on the magnitude of the power supplied by the second distributed power source among the power supplied to the load during self-sustaining operation. A power control device that controls the magnitude of power output by the first distributed power source so that the independent operation prevention function of the power control device that prevents the independent operation of the second distributed power source does not operate. It is a power control method that controls the power output by the first distributed power source in a power control system capable of supplying the power output by the first distributed power source and the second distributed power source to the load during independent operation disconnected from the grid. hand,
A second power control device that controls the power output by the second distributed power source based on the magnitude of the power supplied by the second distributed power source among the power supplied to the load during self-sustaining operation. A power control method for controlling the magnitude of power output by the first distributed power source so that the independent operation prevention function for preventing the independent operation of the second distributed power source does not operate.

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