JP7736992B2 - Microgrid supply and demand control device and microgrid supply and demand control method - Google Patents

Description

This disclosure relates to a microgrid supply and demand control device and a microgrid supply and demand control method.

A microgrid is an energy system that can be suitably applied to, for example, remote islands, and is equipped with storage batteries, load equipment that consumes electricity, and power generation equipment that generates electricity. In order to control the flow of electricity in interconnected lines that include external power systems, it has been proposed to provide a supply and demand control device to control the charging and discharging of power storage devices (storage batteries).

Patent No. 5402566

In a microgrid, the power consumption or power generation in load equipment and power generation equipment can fluctuate on a second-by-second basis, causing changes in power flow. However, conventional microgrid supply and demand control devices such as those described above do not take into consideration the supply and demand balance of the microgrid in response to changes in power flow on a second-by-second basis.

This disclosure has been made in consideration of the above-mentioned problems, and aims to provide a microgrid supply and demand control device and a microgrid supply and demand control method that can appropriately respond to changes in power flow on the order of seconds and balance the supply and demand of a microgrid.

In order to solve the above problem, a supply and demand control device for a microgrid according to one aspect of the present disclosure is a supply and demand control device for a microgrid equipped with a storage battery, and includes a received power acquisition unit that acquires received power received by the microgrid from an external power grid, a transmitted power acquisition unit that acquires transmitted power transmitted by the microgrid to the external power grid, an integrated received power calculation unit that calculates integrated received power by integrating the received power acquired by the received power acquisition unit over a predetermined period, an integrated transmitted power calculation unit that calculates integrated transmitted power by integrating the transmitted power acquired by the transmitted power acquisition unit over the predetermined period, and a power calculation unit that calculates an integrated received power by the integrated received power calculation unit. and a battery control unit that outputs charge/discharge command values to the battery at each control timing that is shorter than the width of the predetermined period, and the battery control unit determines and outputs charge/discharge command values at each control timing so that the difference calculated by the difference calculation unit is offset by charging/discharging in accordance with the charge/discharge command value at each control timing in the next predetermined period, and so that the fluctuation range of the charge/discharge command value at each control timing from the previous charge/discharge command value is equal to or less than a predetermined value.

Furthermore, a microgrid supply and demand control method according to one aspect of the present disclosure is a supply and demand control method for a microgrid equipped with a storage battery, comprising: a received power acquisition step of acquiring received power received by the microgrid from an external power grid; a transmitted power acquisition step of acquiring transmitted power transmitted by the microgrid to the external power grid; an integrated received power calculation step of calculating integrated received power by integrating the received power acquired in the received power acquisition step over a predetermined period; an integrated transmitted power calculation step of calculating integrated transmitted power by integrating the transmitted power acquired in the transmitted power acquisition step over the predetermined period; a difference calculation step of calculating the difference between the output accumulated received power and the accumulated transmitted power calculated in the accumulated transmitted power calculation step; and an output step of outputting a charge/discharge command value to the storage battery at each control timing that is shorter than the width of the predetermined period, wherein the output step determines and outputs a charge/discharge command value for each control timing so that the difference calculated in the difference calculation step is offset by charging/discharging in accordance with the charge/discharge command value for each control timing in the next predetermined period, and so that the fluctuation range of the charge/discharge command value for each control timing from the previous charge/discharge command value is equal to or less than a predetermined value.

One aspect of the present disclosure provides a microgrid supply and demand control device and a microgrid supply and demand control method that can appropriately respond to changes in power flow on the order of seconds and balance the supply and demand of a microgrid.

1 is a diagram illustrating a configuration example of a microgrid that is a control target of a supply and demand control device according to an embodiment of the present disclosure. FIG. 2 is a block diagram showing a specific configuration of a supply and demand control device. 4 is a flowchart showing a specific example of the operation of the supply and demand control device. 10 is a diagram illustrating an example of a specific operation result of the supply and demand control device. FIG. FIG. 10 is a diagram illustrating another example of a specific operation result of the supply and demand control device.

[Embodiment]
Hereinafter, an embodiment of the present disclosure will be described in detail with reference to Fig. 1 and Fig. 2. Fig. 1 is a diagram showing an example of the configuration of a microgrid MG that is a control target of a supply and demand control device 10 according to an embodiment of the present disclosure. Fig. 2 is a block diagram showing a specific configuration of the supply and demand control device 10.

The following explanation will be given of the application to a supply and demand control device included in an EMS (Energy Management System) of a microgrid installed on a remote island. However, the supply and demand control device disclosed herein can also be applied to a supply and demand control device that controls supply and demand for power flow in a microgrid that creates a small-scale energy network, for example, in an industrial area.

<Microgrid MG>
As shown in FIG. 1 , the microgrid MG includes load equipment 1 that consumes power, power generation equipment 2 that generates power, and storage battery 3 that charges and discharges the power. The load equipment 1, power generation equipment 2, and storage battery 3 are interconnected by power lines. The load equipment 1 includes facilities that generate power loads, such as factories and private homes. The power generation equipment 2 includes, for example, renewable energy power generation sources such as solar power generation and wind power generation, and fuel energy power generation sources such as diesel power generation and micro gas turbine power generation. The storage battery 3 is a secondary battery, and charging and discharging are controlled by the supply and demand control device 10 of this embodiment.

An external first power system K1 is connected to the microgrid MG at a connection point C1, and the microgrid MG is capable of receiving power from the first power system K1. An external second power system K2 is connected to the microgrid MG at a connection point C2, and the microgrid MG is capable of transmitting power to the second power system K2. The first power system K1 is, for example, a power company's transmission system and includes at least one transmission system. The second power system K2 is, for example, a power receiving system of a power company, factory, etc. and includes at least one receiving system.

The supply and demand control device 10 of this embodiment acquires received power from the first power system K1 measured at connection point C1. The supply and demand control device 10 of this embodiment also acquires transmitted power from the second power system K2 measured at connection point C2. Using the acquired received power and transmitted power, the supply and demand control device 10 controls the charging and discharging of the storage battery 3 so that the received power and transmitted power are offset over a fixed period of time.

<Supply and demand control device 10>
2 , the supply and demand control device 10 of this embodiment includes a received power acquisition unit 11, a transmitted power acquisition unit 12, an integrated received power calculation unit 13, an integrated transmitted power calculation unit 14, a difference calculation unit 15, and a storage battery control unit 16. The received power acquisition unit 11 is a functional block that acquires received power received by the microgrid MG from a first power system K1 as an external power system. The transmitted power acquisition unit 12 is a functional block that acquires transmitted power transmitted by the microgrid MG to a second power system K2 as an external power system.

The cumulative received power calculation unit 13 is a functional block that calculates the cumulative received power by integrating the received power acquired by the received power acquisition unit 11 over a predetermined period. The cumulative transmitted power calculation unit 14 is a functional block that calculates the cumulative transmitted power by integrating the transmitted power acquired by the transmitted power acquisition unit 12 over a predetermined period. The predetermined period is, for example, any value within a range of 1 second to 60 seconds (e.g., 6 seconds).

The difference calculation unit 15 is a functional block that calculates the difference between the accumulated received power calculated by the accumulated received power calculation unit 13 and the accumulated transmitted power calculated by the accumulated transmitted power calculation unit 14. The battery control unit 16 is a functional block that outputs a charge/discharge command value to the battery 3 at each control timing that is shorter than the width of a predetermined period. As will be described in detail later, the battery control unit 16 determines the charge/discharge command value for each control timing using the difference calculated by the difference calculation unit 15.

The control timing interval is set to any value within a range of 0.1 seconds or more and less than 60 seconds (for example, 1 second). In other words, the control timing is the output timing at which the supply and demand control device 10 outputs charge/discharge command values to the storage battery 3 at predetermined time intervals, and is the output timing of charge/discharge command values for driving the storage battery 3 with the charge/discharge command values output until the next control timing. Furthermore, the control timing interval is set to an interval shorter than the width of the above-mentioned predetermined period, and a value smaller than the value of the predetermined period is selected.

<Example of operation>
Next, a characteristic operation of the supply and demand control device 10 of this embodiment will be described with reference to Fig. 3. Fig. 3 is a flowchart showing a specific example of the operation of the supply and demand control device 10. The supply and demand control device 10 performs the operation shown in the flowchart of Fig. 3 at predetermined intervals.

In the supply and demand control device 10 of this embodiment, the received power acquisition unit 11 acquires the received power from the first power system K1 measured at connection point C1 at each control timing during a predetermined period (step S1). Next, the transmitted power acquisition unit 12 acquires the transmitted power to the second power system K2 measured at connection point C2 at each control timing during a predetermined period (step S2).

Next, the integrated received power calculation unit 13 calculates the integrated received power by accumulating the received power for each control timing during the specified period acquired by the received power acquisition unit 11 (step S3). Next, the integrated transmitted power calculation unit 14 calculates the integrated transmitted power by accumulating the transmitted power for each control timing during the specified period acquired by the transmitted power acquisition unit 12 (step S4).

Next, the difference calculation unit 15 calculates the difference between the integrated received power calculated by the integrated received power calculation unit 13 and the integrated transmitted power calculated by the integrated transmitted power calculation unit 14 for a predetermined period (step S5).

The battery control unit 16 then determines the charge/discharge command value to be output to the battery 3 at each control timing during the next specified period. In this case, the battery control unit 16 determines the charge/discharge command value so that the difference value calculated by the difference calculation unit 15 is offset by charging/discharging in accordance with the charge/discharge command value at each control timing during the next specified period.

Furthermore, the battery control unit 16 determines each charge/discharge command value so that the fluctuation range of the charge/discharge command value at each control timing from the previous charge/discharge command value is equal to or less than a predetermined value (e.g., 10 kW) (step S6). The fluctuation range refers to the magnitude (absolute value) of the fluctuation of the charge/discharge command value from the charge/discharge command value at the previous control timing.

<Operation results>
Next, the operational results of the supply and demand control device 10 of this embodiment will be specifically described with reference to Figures 4 and 5. Figure 4 is a diagram illustrating an example of a specific operational result of the supply and demand control device 10. Figure 5 is a diagram illustrating another example of a specific operational result of the supply and demand control device 10.

First, referring to Figure 4, we will explain an example in which the received power P1 and the transmitted power P2 do not fluctuate within each specified period.

As shown in FIG. 4, in the supply and demand control device 10 of this embodiment, the received power acquisition unit 11 acquires 110 kW as received power P1 every second (every control timing) during a predetermined period of six seconds, for example, from 9:58:54 to 9:59:00. Similarly, the transmitted power acquisition unit 12 acquires 100 kW as transmitted power P2 every second (every control timing).

As shown schematically by arrow A1 in Figure 4, the integrated received power calculation unit 13 calculates 660 kW as the integrated received power (P1 integrated value P1S) for the specified period. As shown schematically by arrow A2 in Figure 4, the integrated transmitted power calculation unit 14 calculates 600 kW as the integrated transmitted power (P2 integrated value P2S) for the specified period.

The difference calculation unit 15 calculates a difference value PD (= P1S - P2S) of 60 kW by subtracting the P2 integrated value P2S from the P1 integrated value P1S. The battery control unit 16 determines the charge/discharge command value for each control timing so that the difference value PD is offset by charging/discharging in accordance with the charge/discharge command value for each control timing in the next predetermined period (the period from 9:59:00 to 9:59:06). Furthermore, when determining the charge/discharge command value for each control timing, the battery control unit 16 determines the charge/discharge command value so that the fluctuation range of the charge/discharge command value from the charge/discharge command value at the previous control timing is 10 kW (predetermined value) or less.

Specifically, when the battery control unit 16 obtains the difference value PD of 60 kW from the difference calculation unit 15, it obtains an average value of 10 kW by dividing the difference value PD of 60 kW by the number of control timings during the specified period, which is six. The battery control unit 16 then determines that the fluctuation range of the obtained average value 10 kW from the charge/discharge command value (0 kW) at the previous control timing (the last control timing of the previous specified period: 9:58:59) is less than the specified value of 10 kW. The battery control unit 16 then determines the obtained average value 10 kW as the charge/discharge command value at each control timing during the next specified period, and outputs it to the battery 3 at each control timing.

As shown schematically by arrow F1 in Figure 4, the battery control unit 16 allocates the integrated charging power of 60 kW to offset the difference value PD to the charge/discharge command value at each control timing for the predetermined 6-second period from 9:59:00 to 9:59:06, and determines 10 kW as the charge/discharge command value at each control timing.

In other words, the battery control unit 16 outputs a charge/discharge command value to the battery 3 instructing it to charge at 10 kW at each control timing during the next specified period. As a result, the battery 3 is controlled to charge at 10 kW at each control timing from 9:59:00 to 9:59:05.

As shown in FIG. 4, the received power acquisition unit 11 acquires 80 kW as received power P1 every second (each control timing) during a predetermined period of six seconds, for example, from 9:59:00 to 9:59:06. Similarly, the transmitted power acquisition unit 12 acquires 100 kW as transmitted power P2 every second (each control timing).

As shown schematically by arrow A3 in Figure 4, the integrated received power calculation unit 13 calculates 480 kW as the integrated received power (P1 integrated value P1S) for the specified period. As shown schematically by arrow A4 in Figure 4, the integrated transmitted power calculation unit 14 calculates 600 kW as the integrated transmitted power (P2 integrated value P2S) for the specified period.

The difference calculation unit 15 calculates the difference value PD (= P1S - P2S) by subtracting the P2 integrated value P2S from the P1 integrated value P1S, resulting in -120 kW. The battery control unit 16 determines the charge/discharge command value for each control timing so that the difference value PD is offset by charging/discharging in accordance with the charge/discharge command value for each control timing in the next predetermined period (the period from 9:59:06 to 9:59:12). Furthermore, when determining the charge/discharge command value for each control timing, the battery control unit 16 determines the charge/discharge command value so that the fluctuation range of the charge/discharge command value from the charge/discharge command value at the previous control timing is 10 kW (predetermined value) or less.

Specifically, if the difference between the calculated average value and the charge/discharge command value at the previous control timing exceeds a predetermined value, the battery control unit 16 determines the charge/discharge command value at the first control timing in the next predetermined period so that the fluctuation range from the previous charge/discharge command value is equal to or less than the predetermined value. The battery control unit 16 then subtracts the determined charge/discharge command value from the difference value PD to update the average value and sequentially determine the charge/discharge command value at the next control timing.

As shown schematically by arrow F2 in Figure 4, the battery control unit 16 appropriately allocates the integrated discharge power of -120 kW to offset the difference value PD for the 6-second period from 9:59:06 to 9:59:12 to determine the charge/discharge command value at each control timing.

The battery control unit 16 obtains the difference value PD of -120 kW for the specified period of 6 seconds from 9:59:00 to 9:59:06 from the difference calculation unit 15, and then calculates the average value of -20 kW by dividing the difference value PD of -120 kW by the number of control timings during the specified period, which is 6.

The battery control unit 16 then determines that the difference between the calculated average value of -20 kW and the charge/discharge command value of 10 kW at the previous control timing (the last control timing of the previous specified period: 9:59:05) exceeds the specified value of 10 kW. The battery control unit 16 then determines the charge/discharge command value at 9:59:06 to be 0 kW so that the fluctuation range of the charge/discharge command value from 10 kW at 9:59:05 is the maximum specified value of 10 kW, and outputs this command to the battery 3. As a result, the battery 3 will not charge or discharge from the control timing at 9:59:06.

Next, to determine the charge/discharge command value at 9:59:07, the battery control unit 16 subtracts the charge/discharge command value of 0 kW at 9:59:06 from the difference value PD (-120 kW), and then divides the subtracted value by the remaining number of control timings (5) to calculate an average value of -24 kW. The battery control unit 16 determines that the fluctuation range of the determined average value of -24 kW from the charge/discharge command value (0 kW) at the previous control timing (the last control timing of the previous specified period: 9:59:06) exceeds the specified value of 10 kW.

The battery control unit 16 then determines the charge/discharge command value at 9:59:07 to be -10 kW, and outputs this command to the battery 3 so that the fluctuation range of the charge/discharge command value from 0 kW at 9:59:06 is the maximum predetermined value of 10 kW. As a result, the battery 3 will discharge 10 kW from the control timing at 9:59:07.

Next, to determine the charge/discharge command value at 9:59:08, the battery control unit 16 subtracts the charge/discharge command value of 0 kW at 9:59:06 and the charge/discharge command value of -10 kW at 9:59:07 from the difference value PD (-120 kW), and then divides the subtracted value by the remaining number of control timings, which is four, to calculate an average value of -27.5 kW. The battery control unit 16 determines that the fluctuation range of the determined average value of -27.5 kW from the charge/discharge command value (-10 kW) at the previous control timing (the last control timing of the previous specified period: 9:59:07) exceeds the specified value of 10 kW.

Then, the battery control unit 16 determines the charge/discharge command value at 9:59:08 to be -20 kW so that the fluctuation range of the charge/discharge command value at 9:59:07 from -10 kW is the maximum predetermined value of 10 kW, and outputs this to the battery 3. As a result, the battery 3 will discharge 20 kW from the control timing at 9:59:08.

Next, to determine the charge/discharge command value at 9:59:09, the battery control unit 16 subtracts the charge/discharge command value of 0 kW at 9:59:06, the charge/discharge command value of -10 kW at 9:59:07, and the charge/discharge command value of -20 kW at 9:59:08 from the difference value PD (-120 kW), and calculates an average value of -30 kW by dividing the subtracted value by the remaining number of control timings (3). The battery control unit 16 determines that the fluctuation range of the determined average value of -30 kW from the charge/discharge command value (-20 kW) at the previous control timing (the last control timing of the previous specified period: 9:59:08) is less than the specified value of 10 kW.

The battery control unit 16 then determines the calculated average value of -30 kW as the charge/discharge command value for each remaining control timing in the specified period and outputs it to the battery 3. As a result, the battery 3 will discharge 30 kW from the control timings of 9:59:09, 9:59:10, and 9:59:11.

Next, referring to Figure 5, we will explain an example in which the transmission power P2 fluctuates within each specified period.

As shown in FIG. 5, in the supply and demand control device 10 of this embodiment, the received power acquisition unit 11 acquires 110 kW as the received power P1 every second (every control timing) during a predetermined period of six seconds, for example, from 9:58:54 to 9:59:00. Similarly, the transmitted power acquisition unit 12 acquires 80 kW, 120 kW, 110 kW, 100 kW, 90 kW, and 120 kW as the transmitted power P2 every second (every control timing).

As shown schematically by arrow A5 in Figure 5, the integrated received power calculation unit 13 calculates 660 kW as the integrated received power (P1 integrated value P1S) for the specified period. As shown schematically by arrow A6 in Figure 5, the integrated transmitted power calculation unit 14 calculates 620 kW as the integrated transmitted power (P2 integrated value P2S) for the specified period.

The difference calculation unit 15 calculates a difference value PD of 40 kW by subtracting the P2 integrated value P2S from the P1 integrated value P1S. The battery control unit 16 determines the charge/discharge command value for each control timing so that the difference value PD is offset by charging/discharging in accordance with the charge/discharge command value for each control timing in the next predetermined period (the period from 9:59:00 to 9:59:06). Furthermore, when determining the charge/discharge command value for each control timing, the battery control unit 16 determines the charge/discharge command value so that the fluctuation range of the charge/discharge command value from the charge/discharge command value at the previous control timing is 10 kW (predetermined value) or less.

Specifically, when the battery control unit 16 obtains the difference value PD of 60 kW from the difference calculation unit 15, it calculates an average value of 6.7 kW by dividing the difference value PD of 40 kW by the number of control timings during the specified period, which is six. Then, the battery control unit 16 determines that the fluctuation range of the calculated average value of 6.7 kW from the charge/discharge command value (0 kW) at the previous control timing (the last control timing of the previous specified period: 9:58:59) is less than the specified value of 10 kW.

The battery control unit 16 then appropriately determines the charge/discharge command values at each control timing during the next specified period and outputs them to the battery 3 so that the average charge/discharge command value at each control timing during the next specified period becomes the calculated average value of 6.7 kW.

As shown by arrow F3 in Figure 5, the battery control unit 16 divides the integrated charging power of 40 kW to offset the difference value PD for the predetermined 6-second period from 9:59:00 to 9:59:06 into, for example, 6 kW, 6 kW, 7 kW, 7 kW, 7 kW, and 7 kW, and determines these as the charge/discharge command values for each control timing. In other words, the battery control unit 16 outputs charge/discharge command values to the battery 3 instructing it to charge 6 kW or 7 kW at each control timing from 9:59:00 to 9:59:05.

As shown in FIG. 5, the received power acquisition unit 11 acquires 80 kW as the received power P1 every second (each control timing) during a predetermined period of six seconds, for example, from 9:59:00 to 9:59:06. Similarly, the transmitted power acquisition unit 12 acquires 90 kW, 80 kW, 70 kW, 60 kW, 70 kW, and 80 kW as the transmitted power P2 every second (each control timing).

As shown schematically by arrow A7 in Figure 5, the integrated received power calculation unit 13 calculates 480 kW as the integrated received power (P1 integrated value P1S) for the specified period. As shown schematically by arrow A8 in Figure 5, the integrated transmitted power calculation unit 14 calculates 450 kW as the integrated transmitted power (P2 integrated value P2S) for the specified period.

The difference calculation unit 15 calculates a difference value PD of 30 kW by subtracting the P2 integrated value P2S from the P1 integrated value P1S. The battery control unit 16 determines the charge/discharge command value for each control timing in the next predetermined period (the period from 9:59:06 to 9:59:12) so that the difference value PD is offset by charging/discharging in accordance with the charge/discharge command value for each control timing. Furthermore, the battery control unit 16 determines the charge/discharge command value so that the fluctuation range of the charge/discharge command value from the charge/discharge command value at the previous control timing is 10 kW (predetermined value) or less.

Specifically, when the battery control unit 16 obtains the difference value PD of 30 kW from the difference calculation unit 15, it obtains an average value of 5 kW by dividing the difference value PD of 30 kW by the number of control timings during the specified period, which is six. The battery control unit 16 then determines that the fluctuation range of the obtained average value 5 kW from the charge/discharge command value (7 kW) at the previous control timing (the last control timing of the previous specified period: 9:59:05) is less than the specified value of 10 kW. The battery control unit 16 then determines the obtained average value 5 kW as the charge/discharge command value at each control timing during the next specified period, and outputs it to the battery 3 at each control timing.

As shown by arrow F4 in Figure 5, the battery control unit 16 allocates the integrated charging power of 30 kW to offset the difference value PD to the charge/discharge command value at each control timing for the predetermined 6-second period from 9:59:06 to 9:59:12, and determines 5 kW as the charge/discharge command value at each control timing. In other words, the battery control unit 16 outputs charge/discharge command values to the battery 3 instructing it to charge 5 kW at each control timing from 9:59:06 to 9:59:12.

As described above, the supply and demand control device 10 of the microgrid MG of this embodiment includes a battery control unit 16 that outputs charge and discharge command values to the storage batteries 3 provided in the microgrid MG at each control timing that is shorter than the width of the predetermined period. The battery control unit 16 determines and outputs charge and discharge command values at each control timing so that the difference value calculated by the difference calculation unit 15 is offset by charging and discharging in accordance with the charge and discharge command value at each control timing in the next predetermined period, and so that the fluctuation range of the charge and discharge command value at each control timing from the previous charge and discharge command value is equal to or less than a predetermined value. As a result, the supply and demand control device 10 of the microgrid MG of this embodiment can reliably balance supply and demand in the microgrid MG by appropriately responding to changes in power flow on the order of seconds, as shown by way of example in Figure 4 or Figure 5.

On the other hand, in the comparative example in which the charge/discharge command value is changed at each control timing, as shown in the comparative example column in Figure 5, the charge/discharge command value increases or decreases in accordance with changes in the value PD of the difference between the received power P1 and the transmitted power P2 at each control timing. For this reason, in the comparative example, the charge/discharge command value had to change, for example, from a charge/discharge command value for charging 30 kW at 9:58:55 to a charge/discharge command value for discharging 10 kW at 9:58:56, thereby increasing the fluctuations in the charge/discharge command value. For this reason, in the comparative example, the charge/discharge power of the storage battery fluctuated significantly on the order of seconds, placing an excessive burden on the storage battery, making it difficult to balance the supply and demand of the microgrid MG in an appropriate manner to respond to changes in power flow on the order of seconds.

Furthermore, in the supply and demand control device 10 of the microgrid MG of this embodiment, the predetermined period is any value within the range of 1 second to 60 seconds. As a result, the supply and demand control device 10 of the microgrid MG of this embodiment can appropriately respond to changes in power flow on the order of seconds and reliably adjust the supply and demand balance of the microgrid MG.

Furthermore, in the supply and demand control device 10 of the microgrid MG of this embodiment, the control timing interval is any value within the range of 0.1 seconds or more and less than 60 seconds. As a result, the supply and demand control device 10 of the microgrid MG of this embodiment can more reliably adjust the supply and demand balance of the microgrid MG by appropriately responding to changes in power flow on the order of seconds.

In the above explanation, the difference calculation unit 15 calculates the difference value by subtracting the integrated transmitted power from the integrated received power, but this embodiment is not limited to this. The difference calculation unit 15 may also be configured to calculate the difference value by subtracting the integrated received power from the integrated transmitted power.

〔summary〕
In order to solve the above-described problems, a supply and demand control device for a microgrid according to one aspect of the present disclosure is a supply and demand control device for a microgrid equipped with a storage battery, and includes a received power acquisition unit that acquires received power received by the microgrid from an external power system, a transmitted power acquisition unit that acquires transmitted power transmitted by the microgrid to the external power system, an integrated received power calculation unit that calculates integrated received power by integrating the received power acquired by the received power acquisition unit over a predetermined period, an integrated transmitted power calculation unit that calculates integrated transmitted power by integrating the transmitted power acquired by the transmitted power acquisition unit over the predetermined period, and an integrated received power calculation unit that calculates integrated received power by integrating the transmitted power acquired by the transmitted power acquisition unit over the predetermined period. and a battery control unit that outputs a charge/discharge command value to the storage battery at each control timing that is shorter than the width of the predetermined period, wherein the battery control unit determines and outputs a charge/discharge command value for each control timing so that the difference value calculated by the difference calculation unit is offset by charging/discharging in accordance with the charge/discharge command value for each control timing of the next predetermined period, and so that the fluctuation range of the charge/discharge command value for each control timing from the previous charge/discharge command value is equal to or less than a predetermined value.

The above configuration makes it possible to provide a microgrid supply and demand control device that can appropriately respond to changes in power flow on the order of seconds and balance the supply and demand of the microgrid.

In the microgrid supply and demand control device according to the above aspect, the predetermined period may be any value within a range of 1 second to 60 seconds.

The above configuration makes it possible to reliably balance supply and demand in the microgrid by appropriately responding to changes in power flow on the order of seconds.

In the microgrid supply and demand control device according to the above aspect, the control timing interval may be any value within a range of 0.1 seconds or more and less than 60 seconds.

The above configuration makes it possible to more reliably balance supply and demand in the microgrid by appropriately responding to changes in power flow on the order of seconds.

Furthermore, a microgrid supply and demand control method according to one aspect of the present disclosure is a supply and demand control method for a microgrid equipped with a storage battery, comprising: a received power acquisition step of acquiring received power received by the microgrid from an external power grid; a transmitted power acquisition step of acquiring transmitted power transmitted by the microgrid to the external power grid; an integrated received power calculation step of calculating integrated received power by integrating the received power acquired in the received power acquisition step over a predetermined period; an integrated transmitted power calculation step of calculating integrated transmitted power by integrating the transmitted power acquired in the transmitted power acquisition step over the predetermined period; a difference calculation step of calculating the difference between the output accumulated received power and the accumulated transmitted power calculated in the accumulated transmitted power calculation step; and an output step of outputting a charge/discharge command value to the storage battery at each control timing that is shorter than the width of the predetermined period, wherein the output step determines and outputs a charge/discharge command value for each control timing so that the difference calculated in the difference calculation step is offset by charging/discharging in accordance with the charge/discharge command value for each control timing in the next predetermined period, and so that the fluctuation range of the charge/discharge command value for each control timing from the previous charge/discharge command value is equal to or less than a predetermined value.

The above configuration provides a microgrid supply and demand control method that can appropriately respond to changes in power flow on the order of seconds and balance the supply and demand of the microgrid.

This disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in the embodiments are also included in the technical scope of this disclosure.

3 Storage battery 10 Supply and demand control device 11 Received power acquisition unit 12 Transmitted power acquisition unit 13 Accumulated received power calculation unit 14 Accumulated transmitted power calculation unit 15 Difference calculation unit 16 Storage battery control unit MG Microgrid K1 First power system K2 Second power system

Claims (4)

A supply and demand control device for a microgrid equipped with a storage battery,
a received power acquisition unit that acquires received power that the microgrid receives from an external power system;
a transmission power acquisition unit that acquires transmission power that the microgrid transmits to an external power system;
an integrated received power calculation unit that calculates an integrated received power by integrating the received power acquired by the received power acquisition unit over a predetermined period;
an integrated transmission power calculation unit that calculates an integrated transmission power by integrating the transmission power acquired by the transmission power acquisition unit over the predetermined period;
a difference calculation unit that calculates a difference between the integrated received power calculated by the integrated received power calculation unit and the integrated transmitted power calculated by the integrated transmitted power calculation unit;
a battery control unit that outputs a charge/discharge command value to the storage battery at each control timing that is shorter than the width of the predetermined period;
The battery control unit
The value of the difference calculated by the difference calculation unit is offset by charging/discharging in accordance with the charge/discharge command value at each control timing of the next predetermined period, and
The charge/discharge command value for each control timing is varied by a predetermined amount from the previous charge/discharge command value.
A supply and demand control device for a microgrid, characterized in that it determines and outputs a charge and discharge command value for each control timing. The microgrid supply and demand control device described in claim 1, characterized in that the predetermined period is any value within the range of 1 second to 60 seconds. The microgrid supply and demand control device described in claim 1 or 2, characterized in that the control timing interval is any value within the range of 0.1 seconds or more and less than 60 seconds. A supply and demand control method for a microgrid equipped with a storage battery, comprising:
a received power acquisition step of acquiring received power received by the microgrid from an external power system;
a transmission power acquisition step of acquiring transmission power to be transmitted by the microgrid to an external power system;
an integrated received power calculation step of calculating an integrated received power by integrating the received power acquired in the received power acquisition step over a predetermined period;
an integrated transmission power calculation step of calculating an integrated transmission power by integrating the transmission power acquired in the transmission power acquisition step over the predetermined period;
a difference calculation step of calculating a difference between the integrated received power calculated in the integrated received power calculation step and the integrated transmitted power calculated in the integrated transmitted power calculation step;
an output step of outputting a charge/discharge command value to the storage battery at each control timing interval shorter than the width of the predetermined period,
The output step includes:
The value of the difference calculated in the difference calculation step is offset by charging/discharging in accordance with the charge/discharge command value at each control timing of the next predetermined period, and
The charge/discharge command value for each control timing is varied by a predetermined amount from the previous charge/discharge command value.
A microgrid supply and demand control method, comprising determining and outputting a charge/discharge command value for each control timing.