JP7096865B2 - Private power generation equipment equipped with power storage means and control device for private power generation equipment - Google Patents

Description

The present invention relates to a private power generation facility equipped with a power storage means and a control device for the private power generation facility.

Patent Document 1 controls a generator connected to a commercial system at normal times and independently driven by a prime mover from the commercial system in the event of a power failure of the commercial system, a power storage means, and charging / discharging of the power storage means. When an increase in load is detected in the operation method of a private power generation facility equipped with a charge / discharge control device, the power storage means outputs (discharges) and temporarily causes the power storage means to bear the entire amount of the increase in load. , The output of the power storage means is gradually reduced at a speed equal to or less than the allowable variable load of the generator, and when the output of the power storage means becomes 0, the load sharing process is terminated to improve the load input rate of the private power generation facility. The operation method of the private power generation facility, which is characterized by the above, is described.

JP-A-2007-6595

In the conventional operation method, when an increase in load is detected, the increased amount is temporarily borne by the power storage means, so that there is a problem that the capacity required for the power storage means becomes large.
An object of the present invention is to reduce the capacity of the power storage means even when the power storage means temporarily bears the increased load.

The invention according to claim 1 is a control device for controlling a private power generation facility including a prime mover for driving a generator and a power storage means, the measuring means for measuring a load, and the electricity generated by the generator. The output of the prime mover is controlled so that it becomes the rated frequency, which is the frequency of electricity that should be when the private power generator is in operation, based on the measured frequency. It is provided with a control means for controlling the power storage means based on a predetermined reference and a measured amount measured by the measuring means, and the predetermined standard is different from the rated frequency and is subject to load fluctuation. It is a standard determined based on whether the prime mover can withstand, and the control means is used until the measured amount exceeds the specified standard when the load is increased and the frequency is below the rated frequency . It is a control device characterized in that power is not output from the power storage means, and power is output from the power storage means when the measured amount exceeds the specified standard.
According to the second aspect of the present invention, when the control means outputs electric power from the electric power storage means and the measured amount falls within the specified standard, the electric power from the electric power storage means is used. The control device according to claim 1, wherein the output is stopped.
The invention according to claim 3 is a control device for controlling a private power generation facility including a prime mover for driving a generator and a power storage means, the measuring means for measuring a load, and the electricity generated by the generator. The output of the prime mover is controlled so that it becomes the rated frequency, which is the frequency of electricity that should be when the private power generation facility is in operation, based on the measured frequency. It is provided with a control means for controlling the power storage means based on a predetermined reference and a measured amount measured by the measuring means, and the predetermined standard is different from the rated frequency and is subject to load fluctuation. It is a standard determined based on whether the prime mover can withstand, and the control means is used until the measured amount exceeds the specified standard when the load is reduced and the frequency exceeds the rated frequency . It is a control device characterized in that the power storage means is not charged, and the power storage means is charged when the measured amount exceeds the predetermined standard.
According to a fourth aspect of the present invention, when the control means is charging the power storage means, the power storage means is charged when the measured amount falls within the specified standard. The control device according to claim 3, wherein the control device is stopped.
The invention according to claim 5 is the invention in which the prime mover is a gas engine, and the predetermined standard is a standard determined based on the number of revolutions per unit time of the engine allowed for the gas engine. The control device according to any one of 1 to 4.
The invention according to claim 6 is the control device according to any one of claims 1 to 5, wherein the measuring means measures the frequency of electricity generated by the generator.
The invention according to claim 7 is the control device according to claim 5, wherein the prime mover is a gas engine, and the measuring means measures the rotation speed of the gas engine.
The invention according to claim 8 is a private power generation facility including a prime mover for driving a generator and a power storage means, in which a measuring means for measuring a load and a frequency of electricity generated by the generator are measured. Based on the measured frequency, the output of the prime mover is controlled so that it becomes the rated frequency, which is the frequency of electricity that should be during the operation of the private power generation facility, and the standard predetermined for each prime mover is determined by increasing or decreasing the load. And the control means for controlling the power storage means based on the measured amount measured by the measuring means, and the predetermined standard is different from the rated frequency, and whether the prime mover can withstand the load fluctuation. A reference determined on the basis of the control means from the power storage means until the measured amount exceeds the defined reference when the load is increased and the frequency is below the rated frequency. It is a private power generation facility characterized in that power is output from the power storage means when the measured amount exceeds the specified standard without outputting power.

According to the invention of the present application, the capacity of the power storage means can be reduced even when the power storage means temporarily bears the increased load.

It is an overall view of the private power generation facility to which the control device which concerns on this invention is applied. It is a flowchart about the control procedure when the load on a generator increases. It is a figure which showed the relationship between the output by control by an embodiment, and a frequency when the load on a generator increased. It is a figure which showed the relationship between the output of a conventional control, and a frequency when the load on a generator increased. It is a flowchart about the procedure of different control of the power storage means when the load on a generator increases. It is a figure showing the relationship between the output and the frequency by different control of the power storage means when the load on a generator increases. It is a flowchart about the control procedure when the load to a generator is reduced. It is a figure which showed the relationship between the output by control by an embodiment, and a frequency when the load on a generator is reduced. It is a figure which showed the relationship between the output of a conventional control, and a frequency when the load on a generator is reduced. It is a flowchart about the procedure of different control of the power storage means when the load on a generator is reduced. It is a figure showing the relationship between the output and the frequency by different control of the power storage means when the load on a generator is reduced.

Hereinafter, the control device according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is an overall view of an embodiment of the present invention.
There are a plurality of consumer devices 2 that consume electric power. Then, the private power generation device 1 and the commercial power system 3 supply electric power to the plurality of demanders 2. When the power from the commercial power system 3 cannot be supplied due to a power outage or the like, the power is supplied to the plurality of demanders 2 only by the private power generation device 1.

The private power generator 1 includes a prime mover 11, a generator 12 driven by the prime mover 11, a frequency control device 13 that measures the frequency of electricity generated by the generator 12 and controls the rotation speed of the prime mover 11, and power generation. A voltage control device 14 that measures the output voltage of the machine 12 to control the output voltage of the generator, a power storage means 15 that can store or discharge electric power, and a charge / discharge control device that controls the charge / discharge of the power storage means 15. 16 and.

As the prime mover 11, a gas engine, a gas turbine engine, a diesel engine, or the like can be used, and can be applied to a cogeneration system.

The generator 12 is driven by the prime mover 11, and the rotation speed of the prime mover 11 per second and the frequency of the electricity generated by the generator 12 have a predetermined relationship. For example, the number of revolutions per second of the prime mover 11 is converted into a frequency tripled by a gear or the like to generate electricity. In the following description, the frequency of electricity means the frequency of electricity generated by the generator 12, and the number of revolutions means the number of revolutions per second.
When the output of the prime mover 11 is constant, the demand for electric power of the demand device 2 increases, and when the supply of electric power from the generator 12 to the demand device 2 increases, the rotation speed of the prime mover 11 decreases.

Therefore, it is possible to detect whether the load on the prime mover 11 is decreasing or increasing by increasing or decreasing the frequency of electricity, and it is possible to detect the relationship between the supply and demand of electric power. When the rotation speed of the engine of the prime mover 11 decreases, it is necessary to increase the output of the prime mover 11 because the demand is larger than the output of the prime mover 11. On the other hand, when the rotation speed of the prime mover 11 is increasing, the demand for electric power is smaller than the output of the prime mover 11, so it is necessary to reduce the output of the prime mover 11.
Further, the magnitude of the difference between the load on the motor 11 and the output of the motor 11 can be grasped by the speed at which the frequency of electricity increases or decreases. For example, it can be said that the load on the prime mover 11 is larger when the speed at which the frequency of electricity decreases is faster than when the speed at which the frequency of electricity decreases is fast and slow.

The frequency control device 13 measures the frequency of electricity at predetermined intervals and controls the output of the prime mover 11 so that the generator 12 operates at a constant frequency. Hereinafter, the frequency of electricity that should be when the private power generation device 1 is operated is referred to as a rated frequency.
When the frequency of electricity falls below the rated frequency, the frequency control device 13 increases the output of the prime mover 11 in order to return to the rated frequency, and controls to increase the frequency of the decreased electricity. When the frequency of electricity exceeds the rated frequency, the output of the prime mover 11 is reduced in order to return to the rated frequency, and control is performed to reduce the increased frequency of electricity.

The power storage means 15 is a means having an ability to store power, and may be any equipment as long as it has high-speed response characteristics. For example, a lead storage battery, a nickel hydrogen storage battery, a lithium ion capacitor, and a lithium ion secondary can be used. Batteries and the like can be used. Here, the high-speed response characteristic refers to a characteristic that the amount of charge and discharge of the power storage means 15 can be increased in a shorter time than the time required for the prime mover 11 to increase the output.

The charge / discharge control device 16 can use a power conversion device that converts the DC power of the power storage means 15 into AC power and also converts the AC output power of the generator 12 into DC power, based on the load applied to the prime mover 11. And control charging and discharging. The load of the motor 11 can be monitored, for example, based on the frequency of electricity and the rotation speed of the motor 11.

When the load applied to the prime mover 11 suddenly increases, the rotation speed of the engine of the prime mover 11 decreases, and the engine causes an abnormal operation such as slipping and stops. As described above, the rotation speed of the motor 11 is set to an allowable value according to the load fluctuation of the motor 11. Hereinafter, the frequency of electricity generated by the generator 12 when the prime mover 11 is operated at a set allowable value rotation speed is referred to as a limit frequency. The charge / discharge control device 16 controls charge / discharge with reference to an electric frequency determined based on the limit frequency.

Hereinafter, the frequency that serves as a reference for charge / discharge control determined based on the permissible value of the rotation speed of the prime mover 11 according to the load fluctuation is referred to as a control frequency. Further, the load fluctuation of the prime mover 11 may increase or decrease, and when the load of the prime mover 11 suddenly increases, the rotation speed of the prime mover 11 decreases, so that the rotation of the prime mover 11 according to the load fluctuation characteristic There is a lower limit to the number tolerance. Hereinafter, the control frequency determined based on the lower limit of the allowable value of the rotation speed of the prime mover 11 is referred to as a lower limit control frequency.

On the contrary, when the load of the prime mover 11 suddenly decreases, the rotation speed of the prime mover 11 increases, so that there is an upper limit of the allowable value of the rotation speed of the prime mover 11 according to the load fluctuation characteristic. Hereinafter, the control frequency determined based on the upper limit of the allowable value of the rotation speed of the prime mover 11 is referred to as an upper limit control frequency.
When the frequency of the prime mover 11 and the frequency of the generator 12 match or are related to each other, the rotation speed of the prime mover 11 may be grasped by measuring the frequency of the generated electricity. When the frequency of electricity exceeds the control frequency, the charge / discharge control device 16 discharges or charges electric power from the electric power storage means 15.

As will be described in detail later, when the frequency of electricity exceeds the limiting frequency and power is discharged from the power storage means 15, the frequency control device 13 controls to increase the output of the prime mover 11. The charge / discharge control device 16 that discharges electric power from the electric power storage means 15 controls to reduce the amount of electric power discharged from the electric power storage means 15 as the output of the prime mover 11 increases. On the contrary, when the electric power storage means 15 is charging the electric power, the control is performed to reduce the output of the motor 11. The charge / discharge control device 16 that charges the electric power storage means 15 with electric power controls to reduce the amount of electric power charged by the electric power storage means 15 as the output of the prime mover 11 decreases.

As described above, in the charge / discharge control device 16, when the frequency of electricity changes to the vicinity of the upper limit of the characteristics of the prime mover 11 when a momentary load fluctuation occurs, the high-speed response characteristics of the power storage means 15 are utilized. The charging and discharging of the power storage means 15 are controlled so as not to exceed the characteristic upper limit of the prime mover 11.

During self-sustaining operation due to system separation, the generator output increases sharply and the load on the prime mover 11 increases, so that the rotation speed of the prime mover 11 decreases. If the rotation speed of the prime mover 11 exceeds the permissible rotation speed due to a sudden decrease, an abnormal operation such as slipping occurs and the motor stops.
The engine used in the cogeneration system generally has an allowance for load fluctuation characteristics (momentary load fluctuations), and cannot respond to momentary load fluctuations that exceed the characteristics during independent operation due to system separation.

Therefore, in the present embodiment, when the load on the generator 12 fluctuates, the electric frequency of the generator 12 is measured, and the electric power is stored based on the electric frequency determined from the allowable amount for the load fluctuation characteristic of the prime mover 11. By controlling the charging and discharging of electric power from the means 15, it is possible to prevent the prime mover 11 from causing an abnormal operation such as slipping and stopping due to a momentary load fluctuation.

When the load on the generator 12 fluctuates, the load may increase or decrease. First, the case where the load increases will be described with reference to the flowchart of FIG.

(Control procedure when the load on the generator 12 increases)
In this flowchart, for example, the operation of the private power generation device 1 when the power supply from the commercial power system is stopped due to a power failure and the load on the generator 12 increases will be described.
When the load on the generator 12 increases, the load on the prime mover 11 increases. When the output of the prime mover 11 is constant and the load on the prime mover 11 increases, the rotation speed of the prime mover 11 decreases. And when the rotation speed of the prime mover 11 decreases, the frequency of electricity also decreases.

In step S1001, the frequency control device 13 that measures the frequency of electricity at predetermined intervals detects that the frequency of electricity is decreasing.

In step S1002, the frequency control device 13 increases the output of the prime mover 11.
By controlling the frequency control device 13 to increase the output of the prime mover, the output of the prime mover 11 is increased. Increasing the output of the prime mover 11 acts to increase the rotation speed of the prime mover 11, but when the load increase on the generator 12 is large, the effect of decreasing the rotation speed of the prime mover 11 due to the increase in load is large, and further electricity. Frequency may drop.

In step S1003, the frequency control device 13 measures the frequency of electricity, determines whether or not the frequency of electricity has reached the rated frequency, and if the frequency of electricity reaches the rated frequency, the process proceeds to step S1009. If the frequency of electricity is not the rated frequency, the process proceeds to step S1004.

In step S1004, the charge / discharge control device 16 measures the frequency of electricity, and determines whether or not it is below the lower limit control frequency determined by the rotation speed of the upper limit of the characteristics of the prime mover 11. If the measured electric frequency is not lower than the lower limit control frequency, the process returns to step S1003. If the measured electric frequency is lower than the lower limit control frequency, the process proceeds to step S1005.

In step S1005, the charge / discharge control device 16 controls the power storage means 15 to discharge the power amount corresponding to the rate at which the frequency decreases to the power storage means 15.
By discharging from the power storage means 15, the load is shared between the generator 12 and the power storage means 15.

In step S1006, the charge / discharge control device 16 reduces the amount of discharge from the power storage means 15 as the output of the prime mover 11 increases, and gradually increases the load ratio of the generator 12.

In step S1007, when the charge / discharge control device 16 gradually reduces the amount of discharge from the power storage means 15, the amount of discharge from the power storage means 15 becomes 0, and the generator 12 receives all the loads. End the load sharing.
Then, the process returns to step S1003, the frequency of electricity is measured, and when the rated frequency is reached, the process proceeds to step 1009.

In step S1009, the frequency control device 13 stops the increase in the output of the prime mover 11. Then, this processing flow ends.

The relationship between the load, output, and frequency in the above processing will be described with reference to FIG. FIG. 3 is a graph showing the magnitude of the load, the generator output, the prime mover output, the power storage means output, and the frequency of electricity from the top.
The load in FIG. 3 is the magnitude of the electric power required by the demand device 2. In FIG. 3, when the load graph goes up, it is necessary to increase the power supplied by the private power generation device 1. The sum of the generator output and the power storage means output is the power supplied by the private power generation device 1 to the demand device 2.

The generator output of FIG. 3 is the magnitude of the electricity generated by the generator 12.
The prime mover output in FIG. 3 is the output of the prime mover 11 that drives the generator 12. The relationship between the generator output and the prime mover output is such that when the prime mover output is smaller than the generator output, the rotation speed of the prime mover 11 decreases. On the other hand, when the prime mover output is larger than the generator output, the rotation speed of the prime mover 11 increases.

The output of the electric storage means of FIG. 3 is the magnitude of the electric power discharged from the electric power storage means 17 according to the instruction of the charge / discharge control device 16. At the first position of the graph of the power storage means output of FIG. 3, charging and discharging are not performed, and when the graph of the power storage means output is above the position, the power storage means 15 is discharging. On the contrary, when there is a graph of the power storage means output below the first position of the graph of the power storage means output, the power storage means 15 is charging.

The frequency in FIG. 3 is the frequency of electricity measured by the frequency control device 13. In FIG. 3, the rated frequency is 50.0 Hz, the limit frequency is 47.5 Hz, and the lower limit control frequency is 48.0 Hz.

In FIG. 3, at first, the load, the generator output, the prime mover output, the power storage means output, the frequency, and all the graphs are operating horizontally and stably. Then, at time t11, the output of the generator 12 increases due to the increase in the load, and the output of the generator 12 increases, so that the rotation speed of the prime mover 11 decreases and the frequency of electricity decreases. .. At time t12, the frequency control device 13 detects that the frequency of electricity is decreasing, and the output of the prime mover 11 is increasing.

Then, at time t13, when the frequency of electricity falls below the lower limit control frequency of 48.0 Hz, electric power is output from the power storage means 15.
The load of the generator 12 is shared by the electric power output from the power storage means 15. Since the prime mover output is increased after time t12, the power output from the power storage means 15 at time t13 is less than the generator output increased at time t11 by the amount of w1 in FIG.

From time t13 to time t14, the prime mover output increases, the amount of power discharged from the power storage means 15 decreases, the amount of power discharged from the power storage means 15 decreases, and the generator output increases. is doing.

When the amount of electric power discharged from the electric power storage means 15 gradually decreases according to the instruction of the charge / discharge control layer 16 and the amount of electric power discharged by the electric power storage means 15 becomes 0 at time t14, the generator 12 causes all the loads 2. Power to. When the generator 12 supplies electric power to all the loads and the frequency of electricity reaches the rated frequency, the increase in the output of the prime mover 11 ends.
After time t14, the load, the generator output, the prime mover output, the power storage means output, and the frequency become constant, and stable operation is achieved.

Further, an example of control by the conventional control method will be described with reference to FIG. FIG. 4 shows the relationship between load, output, and frequency. In the conventional control method, when an increase in the load is detected, the electric power is immediately discharged from the energy storage means, and the increase in the load is temporarily borne by the energy storage means. After that, the output of the power storage means was gradually reduced, and when the output of the power storage means became 0, the load sharing process was terminated.

In FIG. 4, at time t21, when the load increases, the generator output increases and the frequency of electricity begins to decrease. Next, at time t22, the electric power corresponding to the entire amount of the increased load is discharged from the energy storage means. Further, at time t22, the output of the prime mover begins to increase. Between time t22 and time t23, the discharge from the power storage means is gradually reduced according to the increase in the output of the prime mover. At t23, when the amount of discharge from the power storage means becomes 0 and the generator takes on all the increased load, the frequency returns to the rated frequency and the increase in the output of the prime mover is completed. After time t23, the load, the generator output, the prime mover output, the power storage means output, and the frequency are constant, and stable operation is achieved.

As described above, in the conventional control method, at time t22, the power is discharged from the power storage means at the same time as the prime mover output is increased. The increase in the generator output at time t21 and the decrease in the generator output at time t22 are the same. The output of the power storage means bears the total power for the increased load.

On the other hand, the control according to the present embodiment does not output from the power storage means 15 until the frequency of electricity falls below the lower limit control frequency. By increasing the prime mover output until it falls below the lower limit control frequency, the amount of electric power output from the power storage means 15 is reduced. As a result, the total amount of electric power output from the electric power storage means 15 becomes smaller than the total amount of electric power output by the conventional control, and the capacity of the electric power storage means 15 can be reduced.

Further, in the control in the present embodiment, when the frequency of electricity falls below the lower limit control frequency, the electric power is discharged from the power storage means 15, and the power is discharged from the power storage means 15 until the prime mover output compensates for the load increment. Here, the control for stopping the discharge of the electric power from the electric power storage means 15 when the frequency of the electric power exceeds the lower limit control frequency while the electric power is being discharged from the electric power storage means 15 will be further described with reference to FIG. ..

In the flowchart of FIG. 5, the same steps as those of the flowchart of FIG. 2 are assigned the same step numbers, and the description thereof will be omitted.
In this flowchart, when the charge / discharge control device 16 gradually reduces the output from the power storage means 15 as the prime mover output increases in step S1006, the charge / discharge control device 16 uses electricity in step S2007. Determine if the frequency is above the lower limit control frequency. If the frequency of electricity is higher than the lower limit control frequency, the process proceeds to step S2008. In step S2007, if the frequency of electricity does not exceed the lower limit control frequency, the process returns to step S1006.

In step S2008, the charge / discharge control device 16 controls the power storage means 15 and ends the discharge of the power storage means 15. Then, the process returns to step S1003.

The frequency of electricity is measured in step S1003, and when it is determined that the rated frequency has been reached, the process proceeds to step S1009, and the frequency control device 13 controls to stop the increase in the output of the prime mover 11.
Then, this processing flow ends.

The relationship between the load, output, and frequency in the above processing will be described with reference to FIG.
In FIG. 6, at time t31, the output of the generator 12 increases due to the increase in the load. Due to the increase in the output of the generator 12, the rotation speed of the prime mover 11 is reduced and the frequency of electricity is reduced.
Next, at time t32, the prime mover output is increasing.

Then, at time t33, when the frequency of electricity falls below the lower limit control frequency of 48.0 Hz, electric power is output from the power storage means 15. The generator output is reduced by the amount of electric power output from the electric power storage means 15.
At time t34, the frequency of electricity exceeds the lower limit control frequency of 48.0 Hz, and the output of the power storage means is zero. Since the output of the power storage means has become 0, the output of the generator is increasing.

At time t35 and time t37, as in time t33, when the frequency of electricity falls below the lower limit control frequency of 48.0 Hz, electric power is output from the power storage means. The generator output is reduced by the amount of power output from the power storage means.
Further, at time t36 and time t38, the frequency exceeds the lower limit control frequency of 48.0 Hz and the power storage means output is 0, as in the case of time t34. Since the output of the power storage means has become 0, the output of the generator is increasing.

Between time t38 and time t39, the frequency increases because the prime mover output increases.
At time t39, the prime mover output is sufficiently increased and the frequency of electricity is set to the rated frequency of 50.0.
After time t39, the load, the generator output, the prime mover output, the electric storage means output, and the frequency are constant, and stable operation is performed.

As described above, when the frequency of electricity is higher than the lower limit limiting frequency, the amount of power released from the power storage means 15 is suppressed by not discharging the power from the power storage means 15.

Next, the case where the load is reduced will be described with reference to the flowchart of FIG.

(Control procedure when the load on the generator 12 is reduced)
In this flowchart, for example, when the power supply from the commercial power system 3 is stopped due to a power failure and a plurality of demanders 2 are operated by the private power generation device 1, the operation of a certain demander 2 is stopped and the power demand. The operation of the private power generation device 1 when is reduced will be described.
When the demand for electric power decreases and the amount of power generated by the generator 12 decreases, the load on the prime mover 11 decreases and the rotation speed of the prime mover 11 increases. As the number of revolutions of the prime mover 11 increases, so does the frequency of electricity.

In step S3001, the frequency control device 13 that measures the frequency of electricity at predetermined intervals detects that the frequency of electricity is increasing.

In step S3002, the frequency control device 13 reduces the output of the prime mover 11.
By controlling the frequency control device 13 to reduce the output of the prime mover 11, the output of the prime mover 11 is reduced. When the output of the prime mover 11 decreases, the rotation speed of the prime mover 11 decreases, but when the load decrease on the generator 12 is large, the effect of increasing the rotation speed of the prime mover 11 due to the load decrease is large, and further, the prime mover 11 The number of revolutions of the electricity may increase and the frequency of electricity may increase.

In step S3003, the frequency control device 13 measures the frequency of electricity, determines whether or not the frequency of electricity has reached the rated frequency, and if the frequency of electricity reaches the rated frequency, the process proceeds to step S3009. If the frequency of electricity is not the rated frequency, the process proceeds to step S3004.

In step S3004, the charge / discharge control device 16 measures the frequency of electricity and determines whether or not the frequency exceeds the upper limit control frequency. If the frequency of electricity does not exceed the upper limit control frequency, the process returns to step S3003. If the frequency is higher than the upper limit control frequency, the process proceeds to step S3005.

In step S3005, the charge / discharge control device 16 controls the power storage means 15 to charge the power storage means 15 with an amount of power corresponding to the speed at which the frequency increases.
By charging the power storage means 15, the load on the generator 12 increases.
In step 3006, as the output of the prime mover 11 decreases, the charge / discharge control device 16 reduces the amount of charge to the power storage means 15.
When the charge / discharge control device 16 reduces the amount charged to the power storage means 15 and the amount charged by the power storage means 15 becomes 0, in step S3007, the charge / discharge control device 16 ends charging by the power storage means 15. do.

When the charging by the power storage means 15 is completed, the process returns to step S3003, the frequency of electricity is measured, and if the frequency reaches the rated frequency, the process proceeds to step S3009, and the frequency control device 13 stops the decrease in the output of the prime mover 11. Take control.
Then, this processing flow ends.

The relationship between the load, the output, and the frequency in the above processing will be described with reference to FIG. In FIG. 8, the rated frequency is 50.0 Hz, the limit frequency is 52.5 Hz, and the upper limit control frequency is 52.0 Hz.

In FIG. 8, at first, the load, the generator output, the prime mover output, the power storage means output, the frequency, and all the graphs are operating horizontally and stably. Then, at time t41, the output of the generator 12 decreases due to the decrease in load, and the output of the generator 12 decreases, so that the rotation speed of the prime mover 11 increases and the frequency of electricity increases. .. At time t42, the frequency control device 13 detects that the frequency of electricity is increasing, and the output of the prime mover 11 is decreasing.

Then, at time t43, when the frequency of electricity exceeds the upper limit control frequency of 52.0 Hz, the electric power is charged by the electric power storage means 15. Since the output of the prime mover 11 is reduced after the time t42, the magnitude of the electric power charged by the power storage means 15 at the time t43 is only the amount of w2 in FIG. 8 from the amount of the generator output decreased at the time t41. Few.

Between time t43 and time t44, the prime mover output decreases, the amount of power charged by the power storage means 15 decreases, the amount of power charged by the power storage means 15 decreases, and the generator output decreases. is doing.

The amount of electric power charged from the electric power storage means 15 gradually decreases according to the instruction of the charge / discharge control layer 16, and when the amount of electric power charged by the electric power storage means 15 becomes 0 at time t44, the amount of electric power supplied by the generator 12 When the amount of load is balanced and the frequency of electricity reaches the rated frequency, the frequency control device 13 ends the control in which the output of the prime mover 11 is reduced.
After time t44, the load, the generator output, the prime mover output, the power storage means output, and the frequency become constant, and stable operation is achieved.

Further, with reference to FIG. 9, an example of control by the conventional control method will be described.
FIG. 9 shows the relationship between the load, the output, and the frequency. In the conventional control method, when the decrease in load is detected, the power storage means is immediately charged, and the reduced load is temporarily charged in full. After that, the amount of charge by the power storage means was gradually reduced, and when the amount of charge by the power storage means became 0, the charge by the power storage means was terminated.

In FIG. 9, at time t51, when the load decreases, the generator output decreases and the frequency of electricity begins to increase. Next, at time t52, the electric power for the entire amount of the reduced load is charged by the energy storage means. Further, at time t52, the output of the prime mover begins to decrease. Between time t52 and time t53, the amount of electricity charged by the power storage means is gradually reduced according to the decrease in the output of the prime mover. At time t53, when the amount of electricity charged by the electric power storage means becomes 0 and the generator output and the load are in a balanced state, the frequency returns to the rated frequency, and the decrease in the output of the prime mover is completed. After time t53, the load, the generator output, the prime mover output, the power storage means output, and the frequency become constant, and stable operation is achieved.

As described above, in the conventional control method, at time t52, the power storage means starts charging the electric power at the same time as reducing the motor output. The decrease in the generator output at time t51 and the increase in the generator output at time t22 are the same. By charging the power storage means, the load corresponding to the reduced total load is given to the generator.

On the other hand, in the control according to the present embodiment, the charge / discharge control device 16 does not control charging by the power storage means 15 until the frequency of electricity exceeds the upper limit control frequency. By reducing the prime mover output before it falls below the lower limit control frequency, the amount of electricity charged by the power storage means 15 is reduced. Thereby, the total amount of electric power charged by the electric power storage means 15 becomes smaller than the total amount of electric power charged by the conventional control, and the capacity of the electric power storage means 15 can be reduced.

Further, in the control in the present embodiment, when the frequency of electricity exceeds the upper limit control frequency, the power storage means 15 charges the power, and the power storage means 15 charges the power until the prime mover output reduces the output corresponding to the load reduction. Was there. Here, control for stopping the power storage means 15 from charging the power when the frequency of the electricity falls below the upper limit control frequency while the power storage means 15 is charging the power will be described with reference to FIG. ..

In the flowchart of FIG. 10, the same steps as those of FIG. 7 are assigned the same step numbers, and the description thereof will be omitted.
In this flowchart, when the charge / discharge control device 16 gradually reduces the amount of charge charged by the power storage means 15 as the prime mover output decreases in step S3006, the charge / discharge control device 16 determines in step S4007. Determine if the electricity frequency is below the upper and lower limits. If the frequency of electricity is lower than the upper limit control frequency, the process proceeds to step S4008. In step S4007, if the frequency of electricity does not fall below the upper limit control frequency, the process returns to step S3006.

In step S4008, the charge / discharge control device 16 controls the power storage means 15 and ends charging by the power storage means 15. Then, the process returns to step S3003.

The frequency of electricity is measured in step S3003, and when it is determined that the frequency has reached the rated frequency, the process proceeds to step S3009, and the frequency control device 13 controls to stop the decrease in the output of the prime mover 11.
Then, this processing flow ends.

The relationship between the load, the output, and the frequency in the above processing will be described with reference to FIG.
In FIG. 11, at time t61, the output of the generator 12 is reduced due to the decrease in load. Due to the decrease in the output of the generator 12, the rotation speed of the prime mover 11 has increased and the frequency of electricity has increased.
Next, at time t62, the prime mover output is decreasing.

Then, at time t63, when the frequency of electricity exceeds the upper limit control frequency of 52.0 Hz, the power storage means 15 charges the electric power. The generator output is increased by the amount of electric power charged by the electric power storage means 15.
At time t64, the frequency of electricity is below the upper limit control frequency of 52.0 Hz, and the output of the power storage means is 0. Since the output of the power storage means becomes 0, the output of the generator is decreasing.

At time t65 and time t67, similarly to time t63, when the frequency of electricity exceeds the upper limit control frequency 52.0 Hz, the power storage means 15 charges the electric power. The generator output is increasing by the amount of power charged by the power storage means.
Further, at time t66 and time t68, the frequency exceeds the upper limit control frequency 52.0 Hz as in time t64, and the power storage means output is 0. Since the output of the power storage means becomes 0, the output of the generator is decreasing.

Between time t68 and time t69, the frequency of electricity is decreasing because the prime mover output is decreasing.
At time t69, the prime mover output is sufficiently reduced and the electric frequency is set to the rated frequency of 50.0.
After time t69, the load, the generator output, the prime mover output, the electric storage means output, and the frequency are constant, and stable operation is performed.

As described above, when the frequency of electricity is lower than the upper limit frequency, the amount of electricity charged by the power storage means 15 is reduced by not charging the power by the power storage means 15.

In the present embodiment, since the control is performed based on the frequency of electricity without measuring the load of each demand device, the number of measurement points can be reduced.

In the present embodiment, the charge / discharge control device 16 controls the power storage means 15 based on the frequency of the generated electricity, but when the prime mover 11 is an engine, the rotation speed of the engine is measured. By doing so, the load fluctuation may be grasped and controlled.

1 ... Private power generator, 2 ... Demander, 3 ... Commercial power system, 11 ... Motor, 12 ... Generator, 13 ... Frequency control device, 14 ... Voltage control device, 15 ... Power storage means, 16 ... Charge / discharge control device

Claims (8)

It is a control device that controls a private power generation facility equipped with a prime mover for driving a generator and a power storage means.
Measuring means to measure the load and
The frequency of the electricity generated by the generator is measured, and based on the measured frequency, the output of the prime mover is controlled so that the rated frequency is the frequency of the electricity that should be when the private power generation facility is operated, and the load is applied. It is provided with a control means for controlling the power storage means according to a standard predetermined for each of the prime movers and a measured amount measured by the measuring means.
The predetermined standard is different from the rated frequency and is a standard determined based on whether the prime mover can withstand load fluctuations.
When the load increases and the frequency is below the rated frequency, the control means does not output power from the power storage means until the measured amount exceeds the predetermined reference, and the measured amount is not output. A control device characterized in that electric power is output from the electric power storage means when the frequency exceeds the specified standard. The control means stops the output of electric power from the electric power storage means when the measured amount falls within the predetermined standard while the electric power is being output from the electric power storage means. The control device according to claim 1. It is a control device that controls a private power generation facility equipped with a prime mover for driving a generator and a power storage means.
Measuring means to measure the load and
The frequency of the electricity generated by the generator is measured, and based on the measured frequency, the output of the prime mover is controlled so that the rated frequency is the frequency of the electricity that should be when the private power generation facility is operated, and the load is applied. It is provided with a control means for controlling the power storage means according to a standard predetermined for each of the prime movers and a measured amount measured by the measuring means.
The predetermined standard is different from the rated frequency and is a standard determined based on whether the prime mover can withstand load fluctuations.
The control means does not charge the power storage means until the measured amount exceeds the defined reference when the load is reduced and the frequency exceeds the rated frequency, and the measured amount is the measured amount. A control device characterized in that the power storage means is charged when a specified standard is exceeded. The claim is characterized in that, when the power storage means is being charged, the power storage means is stopped from being charged when the measured amount falls within the predetermined standard. Item 3. The control device according to item 3. The prime mover is a gas engine.
The control device according to any one of claims 1 to 4, wherein the predetermined standard is a standard determined based on the number of revolutions per unit time of the engine allowed for the gas engine. The control device according to any one of claims 1 to 5, wherein the measuring means measures the frequency of electricity generated by the generator. The control device according to claim 5, wherein the measuring means measures the rotation speed of the gas engine. It is a private power generation facility equipped with a prime mover to drive a generator and a power storage means.
Measuring means to measure the load and
The frequency of the electricity generated by the generator is measured, and based on the measured frequency, the output of the prime mover is controlled so that the rated frequency is the frequency of the electricity that should be when the private power generation facility is operated, and the load is applied. It is provided with a control means for controlling the power storage means according to a standard predetermined for each of the prime movers and a measured amount measured by the measuring means.
The predetermined standard is different from the rated frequency and is a standard determined based on whether the prime mover can withstand load fluctuations.
When the load increases and the frequency is below the rated frequency, the control means does not output power from the power storage means until the measured amount exceeds the predetermined reference, and the measured amount is not output. A private power generation facility characterized in that power is output from the power storage means when the power exceeds the specified standard.

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