JP2019083667A - Energy management system, power conversion control device, and power conversion control method - Google Patents

Abstract

To efficiently use power from a power source.SOLUTION: An energy management system includes: a power conversion device that is connected with a power system and a load via an AC power line, is connected with a power supply via a DC power line, stores a first power threshold value, and converts DC power from the DC power line into AC power to output it to the AC power line if power supplied from the power system to the load is equal to or more than the first power threshold value; and a power conversion control device that is connected with the power conversion device via a communication path, receives measurement information measured at the DC power line and the AC power line from the power conversion device, determines whether the measurement information satisfies a change condition, and if it is determined that the measurement information satisfies the change condition, generates control information to give instructions to change the first power threshold value, and transmits the control information to the power conversion device.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an energy management system.

  In recent years, electric vehicles that run by driving a motor with electric power supplied from a battery have come to be used, and cases of charging the battery from a household outlet, and conversely, electric power charged in the battery There are known cases of supplying equipment.

  Patent Document 1 describes that the charge and discharge device charges the electric vehicle from the grid power and the solar power generation device, and supplies the electric power discharged from the electric vehicle to the electric device through the power distribution device. There is.

  Moreover, HEMS (Home Energy Management System) is a system which monitors, displays, and controls the power consumption of each home. In the HEMS, the HEMS controller (HEMS controller) is an electric vehicle such as an EV (Electric Vehicle) or a PV (Photovoltaic Power Generation) via a PCS (Power Conditioning Subsystem). Connected to The PCS is a device that regulates direct current and alternating current power among various power devices and power systems. The HEMS controller constantly obtains status information of various power devices for monitoring, and sends control information to the power devices for control.

Unexamined-Japanese-Patent No. 2014-054010

  However, assuming that the power from the power source in the home including the EV is supplied to the load in the home, it is necessary to consider the balance of power supply and demand between the grid power, the power source and the load. Also, due to the operation of the PCS, power from the power supply may not be efficiently used.

  Then, an object of this invention is to provide the technique which utilizes the electric power from a power supply efficiently.

  In order to solve the above problems, an energy management system according to an aspect of the present invention is connected to a power system and a load via an AC power line, connected to a power supply via a DC power line, and stores a first power threshold. A power conversion device for converting DC power from the DC power line into AC power and outputting the AC power to the AC power line when the power supplied from the power system to the load is equal to or greater than the first power threshold; And the measurement information measured on the DC power line and the AC power line is received from the power converter, and it is determined whether the measurement information satisfies the change condition, and the measurement is performed. If it is determined that the information satisfies the change condition, control information is generated to instruct changing the first power threshold, and the control information is transmitted to the power conversion device. It comprises a force converter control device. The power converter changes the first power threshold stored in the power converter according to the control information.

  According to one aspect of the present invention, power from the power supply can be efficiently used.

1 shows the configuration of a regional energy management system according to an embodiment of the present invention. The configuration of the HEMS controller 100 is shown. 7 shows the configuration of the PCS 300. 9 shows a PCS result information table 111. 7 shows a PCS power threshold table 112. The charge and discharge plan table 113 is shown. FIG. 16 shows suppression of EV discharge power by UPR power threshold. FIG. 7 shows the improvement of EV discharge power due to the reduction of UPR power threshold. 17 shows outage of PCS 300 by UPR power threshold. 8 illustrates avoiding a stop of the PCS 300 by increasing the UPR power threshold. 7 illustrates a power threshold management process. 11 shows a variation of the power threshold management process.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows the configuration of a regional energy management system according to an embodiment of the present invention.

  The regional energy management system of the present embodiment includes the HEMS center 500 and a plurality of HEMSs 400. The plurality of HEMSs 400 are respectively provided to a plurality of homes located in a specific area. The HEMS 400 includes the HEMS controller 100, the PCS 300, the PV 14, the charge and discharge stand 15, and the EV 16. In this figure, a solid line represents a power line and a broken line represents a communication line. The communication line may be a wired communication path or a wireless communication path.

  The HEMS controller 100 is connected to the PCS 300 via a communication line. The HEMS controller 100 is connected to the router 520 via a communication line. The PCS 300 is connected to the distribution board 410 via a power line (AC power line). The PCS 300 is connected to the PV 14 via a power line (DC power line). The PCS 300 is connected to the charge and discharge stand 15 via a power line (DC power line). The charge and discharge stand 15 is connected to the EV 16 through a power line. The distribution board 410 is connected to the power meter 420 via a power line and to the load 150 via a power line. The power meter 420 is connected to the power system 600 via a power line, and is connected to the PCS 300 via a communication line. The power meter 420 measures the purchased system power (purchased power) flowing from the power system 600 to the distribution board 410 as a purchased system power measurement value, and sells power (reverse flow power) flowing from the distribution board 410 to the power system 600 Is measured as the sale power measurement value, and the purchased system power measurement value and the sale sale power measurement value are transmitted to the PCS 300 via the communication line. The router 520 is connected to the communication network 510. The HEMS center 500 is connected to the communication network 510. Hereinafter, a device capable of supplying DC power to the PCS 300 by power generation or discharge in the HEMS 400, such as the PV 14 and the EV 16, is referred to as a power supply. The power source may be both or one of the PV 14 and the EV 16. The power source may include another renewable energy power generation device such as a wind power generation device, or may include a storage battery.

  The HEMS 400 is a system that monitors, displays, and controls the power supply and demand of each home. If the home has power, monitoring, display and control of the power is provided by the HEMS 400. The PCS 300, the PV 14, the charge and discharge stand 15, the EV 16, and the power meter 420 are targets of monitoring, display, and control by the HEMS.

  The PV 14 is a power device that generates electric power by sunlight. The power generated by the PV 14 is supplied to the EV 16 in the home, the load 150, or the power system 600 via the PCS 300.

  The charge and discharge stand 15 has a connector for connecting to the EV 16. Instead of the charge and discharge stand 15, a connector may be provided in the PCS 300.

  The EV 16 is an electric car that travels with the power stored in a built-in storage battery. The EV 16 is connected to the PCS 300 via the charge and discharge stand 15. PCS 300 can charge the storage battery of EV 16 using power from power system 600 and PV 14. In addition, the power stored in the storage battery of the EV 16 can be supplied to the load 150 and the power system 600 via the PCS 300. The start and stop of charging to the EV 16 can be controlled from both the charge and discharge stand 15 and the HEMS controller 100. Note that, instead of the EV 15, another transport machine such as a plug-in hybrid vehicle or an electric two-wheeled vehicle, which includes a storage battery and can be connected to a power line to charge the storage battery may be used. Thus, the PV 14 and the EV 16 can be effectively used by charging the EV 15 using the surplus of the power generated by the PV 14 or reducing the power from the electric power system 600 by discharging the EV 15 or the like. .

  The PCS 300 is connected to power devices such as the PV 14, the charge and discharge stand 15, and the EV 16, adjusts the power input / output by these power devices, and measures the state of the power input / output by each power device. The power input to and output from the power equipment and the PCS 300 includes DC power and AC power, so the PCS 300 also performs conversion between DC and AC. In addition, since the HEMS 400 of the present embodiment includes the EV 16 that performs discharge, the PCS 300 can handle both the power flow in the direction from the power system 600 to the power supply and in the direction from the power supply to the power system 600. It is facing PCS. The PCS 300 generates and stores PCS performance information indicating the state measured by the PCS 300 and the power meter 420, and transmits the generated information to the HEMS controller 100. For example, the PCS 300 generates a PV generated power measurement value by measuring the PV generated power output from the PV 14 to the distribution board 410 by the power generation of the PV 14, and an EV output from the PCS 300 to the EV 16 for charging the EV 16 By measuring the charging power, an EV charging power measurement value is generated, and by measuring the EV discharging power output from the EV 16 to the distribution board 410 by the discharge of the EV 16, an EV discharging power measurement value is generated.

  The HEMS center 500 externally acquires power related information that affects the power supply and demand in the area, such as regional weather information, and acquires PCS performance information from a plurality of HEMSs 400. The HEMS center 500 further creates charge / discharge plan information of the EVs 16 in the plurality of HEMSs 400 based on the power supply / demand information and the PCS performance information, and transmits the charge / discharge plan information to the plurality of HEMSs 400 via the communication network 510. That is, the HEMS center 500 adjusts the power supply and demand in the area by planning charge and discharge in the area.

  The HEMS controller 100 is a controller that controls the HEMS 400. The HEMS controller 100 acquires and stores state information from the PCS 300 at a preset timing, and controls the power supply using the PCS 300 at the preset timing.

  FIG. 2 shows the configuration of the HEMS controller 100.

  The HEMS controller 100 includes a central processing unit (CPU) 101, an input unit 103, an output unit 104, a storage unit 110, and a communication unit 109. The input unit 103 is, for example, an input device such as a keyboard and buttons. The output unit 104 is, for example, a display device such as a display. The communication unit 109 communicates with the PCS 300, the router 520, and the like according to an instruction from the CPU 101.

  The storage unit 110 is a random access memory (RAM), a hard disk drive (HDD), a flash memory, or the like. The storage unit 110 stores programs for the control instruction unit 106, the screen display unit 107, and the control instruction calculation unit 108. The storage unit 110 further stores a PCS performance information table 111, a PCS power threshold table 112, a charge and discharge plan table 113, and the like.

  The CPU 101 executes the control instruction unit 106, the screen display unit 107, and the control instruction calculation unit 108 in accordance with the program stored in the storage unit 110.

  Control instruction calculation unit 108 periodically receives the PCS performance information from PCS 300 at preset time intervals using communication unit 109, and stores the received PCS performance information as PCS performance information table 111 as storage unit 110. Save to Control instruction calculation unit 108 further calculates a PCS power threshold which is a settling value of PCS 300 based on PCS performance information table 111 and PCS power threshold table 112, and stores the calculated PCS power threshold in PCS power threshold table 112. . The PCS power threshold is a power threshold for detecting reverse flow power from the HEMS 400 to the power system 600. RPR (reverse power relay) power threshold, power failure of the power system 600, etc. The power threshold for detecting the power shortage to the UPR (underpower relay) is a power threshold or the like. Control instruction calculation unit 108 further receives the charge / discharge plan from HEMS center 500 using communication unit 109, and stores it as charge / discharge plan table 113 in storage unit 110.

  Control instructing unit 106 transmits PCS control information including the PCS power threshold to PCS 300 using communication unit 109. Control instructing unit 106 further transmits PCS control information including a charge / discharge power plan value, which is a planned value of current charge / discharge power, from charge / discharge plan table 113 to PCS 300 using communication unit 109. The charge / discharge power plan value is either a charge power plan value which is a plan value of charge power of the EV 16 or a discharge power plan value which is a plan value of discharge power of the EV 16.

  The screen display unit 107 causes the output unit 104 to display the contents of the PCS performance information table 111, the PCS power threshold table 112, the charge and discharge plan table 113, and the like. For example, the screen display unit 107 may display the PCS power threshold on the output unit 104, or may display the charge / discharge power planned value on the output unit 104.

  The present invention can be applied to various energy management systems (xEMS) such as a factory energy management system (FEMS) provided in a factory and a building energy management system provided in a building instead of the HEMS 400. Moreover, the HEMS center 500 may be a controller of a community energy management system (CEMS) provided in a region.

  The PCS 300 will be described below.

  FIG. 3 shows the configuration of the PCS 300.

  The PCS 300 includes a photovoltaic power input unit 20, a grid power input / output unit 21, a vehicle power input / output unit 22, a DC-DC power conversion unit 23a, an AC-DC power conversion unit 23b, a DC-DC power conversion unit 23c, And a communication unit 27 and a storage unit 28. In this figure, a solid line represents a power line, and a broken line represents a communication line.

  The photovoltaic power input unit 20 is connected to the PV 14 via a power line, and receives DC power generated by the PV 14. The grid power input / output unit 21 is connected to the distribution board 410 via a power line, receives AC power from the power system 600 from the distribution board 410, and outputs AC power output from the AC-DC power conversion unit 23b. It is sent to the distribution board 410 or the like. The automobile power input / output unit 22 is connected to the charge / discharge stand 15 via a power line, receives from the DC power discharged by the EV 16 via the charge / discharge stand 15, or is direct current output by the DC-DC power conversion unit 23c. The electric power is sent to the EV 16 through the charge and discharge stand 15. The DC-DC power converter 23 a converts the voltage of the DC power from the photovoltaic power input unit 20. The DC-DC power converter 23c converts the voltage of the DC power from the automobile power input / output unit 22 and sends it to the AC-DC power converter 23b, or the DC-DC power converter 23a and the AC-DC power converter It converts the voltage of the DC power from 23 b and sends it to the vehicle power input / output unit 22. The AC-DC power converter 23 b converts DC power from the DC-DC power converter 23 a and the DC-DC power converter 23 c into AC power as an inverter and sends it to the grid power input / output unit 21, or as an converter The AC power from the grid power input / output unit 21 is converted into DC power and sent to the DC-DC power conversion unit 23c.

  The grid power input / output unit 21 of the present embodiment is connected to the distribution board 410 by a single-phase two-wire power line. The power line may be a single-phase three-wire system, a three-phase three-wire system, or the like. Also, the PCS power threshold may be represented by a power amount, a current or the like instead of the power.

  The communication unit 27 is connected to the HEMS controller 100 via the communication line, receives the PCS control information from the HEMS controller 100, stores the PCS control information in the storage unit 28, and transmits the PCS performance information stored in the storage unit 28 to the HEMS controller 100. Send. Further, the communication unit 27 receives the measurement value of the power from the power meter 420.

  The control unit 25 stores the measured values of the power measured by the DC-DC power conversion unit 23a, the AC-DC power conversion unit 23b, the DC-DC power conversion unit 23c, and the power meter 420 in the storage unit 28 as PCS performance information. Do.

  The control unit 25 stores the PCS control information received from the HEMS controller 100 in the storage unit 28, and based on the PCS control information, the DC-DC power converter 23a, the AC-DC power converter 23b, and the DC-DC power. The conversion unit 23c is controlled. The PCS control information indicates a PCS power threshold set in the PCS 300 or a charge / discharge power plan value for the EV 16. When the charge / discharge power plan value indicates a charge power plan value which is a plan value of charge power of EV 16, control unit 25 controls DC-DC power converter 23a, AC-DC power converter 23b, DC-DC power converter By controlling 23 c, the power whose upper limit is the charging power planned value is converted to the DC-DC power converter 23 c and sent to the vehicle power input / output unit 22. When the charge / discharge power plan value indicates a discharge power plan value which is a plan value of discharge power of EV 16, control unit 25 controls DC-DC power converter 23a, AC-DC power converter 23b, DC-DC power converter By controlling 23c, the power with the discharge power planned value as the upper limit is received from the vehicle power input / output unit 22 and converted into the DC-DC power conversion unit 23c.

  Hereinafter, the information stored in the HEMS controller 100 will be described.

  FIG. 4 shows the PCS performance information table 111.

  The PCS result information table 111 has an entry for each measured time. The entry corresponding to a certain time is measured at the time, the PV generated power measurement value [W] measured at the time, the purchased system power measurement value [W] measured at the time, and the time It includes the sold electricity power measurement value [W], the EV charge power measurement value [W] measured at the time, and the EV discharge power measurement value [W] measured at the time. Note that the PCS performance information table 111 may have an entry of the latest time, or may have a plurality of entries respectively corresponding to a plurality of times. The power meter 420 may be connected to the HEMS controller 100 via a communication line. In this case, the HEMS controller 100 receives the purchased system power measurement value and the power sale power measurement value measured by the power meter 420, and registers them in the PCS performance information table 112.

  FIG. 5 shows the PCS power threshold table 112.

  The PCS power threshold table 112 indicates the PCS power threshold set in the PCS 300. The PCS power threshold includes the RPR power threshold and the UPR power threshold. Note that the RPR power threshold may be referred to as the RPR settling value. The UPR power threshold may be referred to as the UPR settling value.

  FIG. 6 shows the charge and discharge plan table 113.

  The charge and discharge plan table 113 shows the charge and discharge plan received from the HEMS center 500, and has an entry for each time. The entry corresponding to a certain time is the relevant time, the charge power planned value [W] which is the planned value of the EV charging power at the relevant time, and the discharged power plan value [W] which is the planned value of the EV discharged power at the relevant time. And]. If one of the charge power plan value and the discharge power plan value is positive, the other is zero.

  Hereinafter, the operation of the PCS 300 based on the PCS power threshold will be described.

  The PCS power threshold may be, for example, a UPR power threshold defined by a standard such as a grid connection specification, and is about 3% of the rated power of the output (inverter) from the PCS 300 to the distribution board 410. The RPR power threshold is, for example, about 5% of the rated power.

  In the present embodiment, the UPR standard value and the UPR tolerance are defined for the UPR power threshold based on the standard, and the UPR tolerance is defined based on them. The UPR allowable range is defined by the UPR lower limit value and the UPR upper limit value. The UPR lower limit is UPR standard value-UPR tolerance, and the UPR upper limit is UPR standard value + UPR tolerance. For example, the UPR standard value is 3% of the rated power and the UPR tolerance is 1% of the rated power.

  Further, in the present embodiment, the RPR standard value and the RPR tolerance are determined with respect to the RPR power threshold based on the standard, and the RPR tolerance is determined based on them. The RPR allowable range is determined by the RPR lower limit value and the RPR upper limit value. The RPR lower limit is RPR standard value-RPR tolerance, and the RPR upper limit is RPR standard value + RPR tolerance. For example, the RPR standard value is 5% of the rated power, and the RPR tolerance is 1% of the rated power.

  Based on the PCS performance information, the PCS 300 stops the PCS 300 when the power sale power measurement value exceeds the RPR power threshold for a certain period of time. After that, the PCS 300 resumes operation by the user performing a return operation on the PCS 300.

  Here, the power consumption by the load 150 is called household power consumption. When home power consumption is equal to or less than the UPR power threshold, the PCS 300 does not convert or output power from the power supply in order to prioritize purchased grid power over EV discharge power or PV generated power. In addition, when the UPR power threshold is insufficient with respect to home power consumption, the PCS 300 compensates the shortfall by the EV discharge power with the discharge power planned value as the upper limit. In other words, when the purchased system power is equal to or greater than the UPR power threshold, the PCS 300 converts the power from the power supply and outputs the converted power to the distribution board 410. As a result, the EV discharge power becomes the lower one of the difference value obtained by subtracting the UPR power threshold value from the home power consumption and the discharge power planned value. In addition, when the sum of the UPR power threshold and the EV discharge power is insufficient for home power consumption, the shortage is compensated by the purchased grid power. When the UPR power threshold is insufficient for household power consumption, the PCS 300 may compensate for the shortage by the PV generated power. In this case, if the sum of the UPR power threshold, the EV discharge power, and the PV generated power is insufficient with respect to the household power consumption, the shortage is compensated by the purchased grid power.

  Hereinafter, a specific example of the operation of the PCS 300 based on the PCS power threshold will be described. Here, the PV generated power is set to 0 for simplicity.

  First, as a comparative example, the operation of the PCS when the change of the UPR power threshold is not performed is shown.

  FIG. 7 shows the suppression of the EV discharge power by the UPR power threshold of the comparative example.

  State A1 shows a state in which the UPR power threshold is set to 100 W, the discharge power planned value is set to 70 W, and the household power consumption is 170 W. In this state A1, the purchased system power is 100 W equal to the UPR power threshold, and the EV discharge power is 70 W equal to the difference between household power consumption and the UPR power threshold.

  In the subsequent state A2, when the household power consumption is reduced to 120 W, since the EV discharge power is 70 W, the purchased system power is temporarily reduced to 50 W.

  In state A3 after that, the purchased system power increases to 100 W equal to the UPR power threshold, and the difference value obtained by subtracting the UPR power threshold from the household power consumption becomes 20 W, so the PCS 300 makes the EV discharge power equal to or less than the difference value To suppress the EV discharge power. As a result, the EV discharge power is 20 W.

  According to this operation, the EV discharge power becomes significantly lower than the discharge power planned value.

  Next, the case where the UPR power threshold is reduced by the HEMS controller 100 of the present embodiment will be described.

  FIG. 8 shows the improvement of the EV discharge power due to the reduction of the UPR power threshold.

  In the state B1, the discharge power plan value and the home power consumption are the same as the state A1, but reduce the UPR power threshold from 100 W to 70 W. In this state B1, similarly to the state A1, the purchased system power is 70 W equal to the UPR power threshold, and the EV discharge power is 100 W equal to the difference value obtained by subtracting the UPR power threshold from the home power consumption.

In the subsequent state B2, when the home power consumption is reduced to 120 W, since the EV discharge power is 100 W, the purchased system power is temporarily reduced to 20 W.

  In the subsequent state B3, the purchased system power is increased to 70 W equal to the UPR power threshold, and the difference value obtained by subtracting the UPR power threshold from the home power consumption becomes 50 W. Therefore, the PCS 300 matches the power received from the EV 16 with the difference value. So as to suppress. As a result, the EV discharge power is 50 W.

  According to this operation, the EV discharge power can be increased and the purchased system power can be decreased by reducing the UPR power threshold as compared with the state A3.

  Next, as a comparative example, the operation of the PCS when the UPR power threshold is not changed is shown.

  FIG. 9 shows the shutdown of the PCS 300 by the UPR power threshold of the comparative example.

  The state C1 shows a state in which the UPR power threshold is set to 50 W, the RPR power threshold is set to 80 W, the discharge power planned value is set to 150 W, and the household power consumption is 200 W. In this state C1, the purchased system power is 50 W equal to the UPR power threshold, and the EV discharge power is 150 W equal to the difference between household power consumption and the UPR power threshold.

  In the subsequent state C2, when the household power consumption is reduced to 50 W, the EV discharge power is 150 W, so that the reverse flow power to power system 600 is temporarily a value obtained by subtracting household power consumption from EV discharge power. It will be 100W.

  In the subsequent state C3, since the backward flow power exceeds the RPR power threshold, the PCS 300 stops and does not convert the power from the EV 16. As a result, the EV discharge power is 0 W, and the purchased system power is 50 W, which is equal to household power consumption.

  According to this operation, since the PCS 300 is stopped, power from the EV 16 can not be utilized even if home power consumption exceeds the UPR power threshold thereafter. Furthermore, in order to use the power from the EV 16 thereafter, work and time are required to restore the PCS 300.

  Next, a case where the UPR power threshold is increased by the HEMS controller 100 of the present embodiment will be described.

  FIG. 10 illustrates the avoidance of outages of the PCS 300 by increasing the UPR power threshold.

  In the state D1, the RPR power threshold, the discharge power planned value, and the home power consumption are the same as the state C1, but the UPR power threshold is increased from 50 W to 80 W. In this state D1, as in the state C1, the purchased system power is 80 W equal to the UPR power threshold, and the EV discharge power is 120 W equal to the difference between home power consumption and the UPR power threshold.

  In the subsequent state D2, when the household power consumption is reduced to 50 W, the EV discharge power is 120 W, so that the reverse flow power to power system 600 temporarily reduces the household power consumption from the EV discharge power. It will be 70W.

  In subsequent state D3, the PCS 300 does not stop because the reverse flow power does not exceed the RPR power threshold. In addition, the PCS 300 receives no power from the EV 16 because the home power consumption is lower than the UPR power threshold. As a result, the EV discharge power is 0 W, and the purchased grid power is 50 W, which is equal to household power consumption.

  According to this operation, as compared with the state C3, the PCS 300 does not stop, and therefore, the task of returning the PCS 300 is not required. Also, if the home power consumption subsequently exceeds the UPR power threshold, the power from the EV 16 can be converted immediately and supplied to the load 150.

  As described above, when the UPR power threshold is too high, the ratio of purchased system power to home power consumption increases, and the EV discharge power is suppressed. Also, if the UPR power threshold is too low, the PCS 300 will stop when reverse power flow occurs.

  Hereinafter, a power threshold management process in which the HEMS controller 100 manages the UPR power threshold of the PCS 300 to prevent the suppression of the EV discharge power and the stop of the PCS 300 will be described.

  FIG. 11 shows a power threshold management process.

  The HEMS controller 100 starts the power threshold management process at intervals of a predetermined management time. The management time is, for example, one minute.

  In S110, the HEMS controller 100 performs PCS performance information collection processing for collecting PCS performance information from the PCS 300. The PCS performance information includes a PV generated power measurement value, a purchased system power measurement value, a power sale power measurement value, an EV charge power measurement value, and an EV discharge power measurement value. Thereafter, in S120, the HEMS controller 100 performs PCS performance information registration processing for registering the collected PCS performance information in the PCS performance information table.

  After that, in S210, the HEMS controller 100 acquires the PV generated power measurement value, the purchased system power measurement value, the sale electric power measurement value, the EV charge power measurement value, and the EV discharge power measurement value from the PCS performance information table. Perform acquisition processing. Thereafter, in S220, the HEMS controller 100 performs PCS power threshold value acquisition processing for acquiring the UPR power threshold value from the PCS power threshold value table.

  Then, in S310, the HEMS controller 100 determines the power sale power measurement value as the reverse flow power, and determines whether the reverse flow power is positive.

  When it is determined that the backward flow power is positive (S310: Y), the HEMS controller 100 adds a predetermined UPR addition value to the UPR power threshold in S320 to thereby generate a new UPR power threshold (instruction value). Perform UPR power threshold addition processing to calculate This allows the UPR power threshold to be increased. If the UPR addition value is excessively large, this leads to an increase in purchased system power and suppression of the EV discharge power, so it is desirable that the UPR addition value be smaller than the UPR tolerance.

  After that, the HEMS controller 100 saves the new UPR power threshold in the PCS 300 by transmitting PCS control information indicating the new UPR power threshold to the PCS 300 in S410, and the new UPR power threshold in the PCS power threshold table 112 Perform UPR power threshold update processing to be stored, and end this flow. Here, the HEMS controller 100 limits the new UPR power threshold to the UPR tolerance if the new UPR power threshold is outside the UPR tolerance. For example, if the new UPR power threshold falls below the UPR lower limit, the HEMS controller 100 makes the new UPR power threshold equal to the UPR lower limit. Also, if the new UPR power threshold exceeds the UPR upper limit, the HEMS controller 100 makes the new UPR power threshold equal to the UPR upper limit.

  When it is determined that the reverse flow power is not positive (S310: N), the HEMS controller 100 calculates a new UPR power threshold (instruction value) by subtracting the UPR subtraction value from the UPR power threshold in S350. Perform threshold subtraction processing. It is desirable that the UPR subtraction value be smaller than the UPR tolerance, as an excessively large UPR subtraction value leads to an increase in backward flow power and a stop of the PCS.

  After that, in S360, the HEMS controller 100 calculates a home power consumption measurement value which is a measurement value of home consumption power based on the PCS performance information table, and UPR which is a target value of UPR power threshold value based on the home power consumption measurement value. The power threshold target value is calculated, and it is determined whether the UPR power threshold is smaller than the UPR power threshold target value. Here, the HEMS controller 100 calculates the home power consumption measurement value by the following equation.

Household power consumption measurement value = PV generated power measurement value + purchased system power measurement value-selling power power measurement value-EV charge power measurement value + EV discharge power measurement value

  Furthermore, the HEMS controller 100 calculates a UPR power threshold target value by multiplying the home power consumption measurement value by a predetermined UPR coefficient. The UPR factor is greater than zero and less than one, for example 0.6.

  If it is determined that the UPR power threshold is equal to or higher than the UPR power threshold target value (S360: N), the HEMS controller 100 shifts the processing to S350. This allows the HEMS controller 100 to reduce the UPR power threshold until the UPR power threshold is less than the UPR power threshold target value. In other words, if the current UPR power threshold is smaller than the UPR power threshold target value, the HEMS controller 100 does not decrease the UPR power threshold. The HEMS controller 100 may make the UPR power threshold equal to the UPR power threshold target value.

  When it is determined that the UPR power threshold is smaller than the UPR power threshold target value (S360: Y), the HEMS controller 100 transmits the PCS control information indicating the UPR power threshold to the PCS 300 in S410 to thereby set the UPR power threshold PCS300. Save to and exit this flow.

  Note that, in S410, the HEMS controller 100 may transmit PCS control information indicating the amount of change of the UPR power threshold to the PCS 300 instead of the UPR power threshold. Also, the PCS 300 may store the amount of increase and decrease of the UPR power threshold. In this case, the HEMS controller 100 transmits PCS control information indicating increase or decrease of the UPR power threshold to the PCS 300 instead of the UPR power threshold in S410, and the PCS 300 increases the UPR power threshold according to the PCS control information. Increasing by an amount or decreasing the UPR power threshold by a decreasing amount may be performed.

  The screen display unit 107 causes the output unit 104 to display a screen indicating the state of the HEMS 400. For example, the screen displays a UPR power threshold value, an EV discharge power measurement value, a purchased grid power measurement value, a home power consumption measurement value, and the like.

  According to the above power threshold management process, the HEMS controller 100 can optimize the UPR power threshold. This can prevent the stop of the PCS 300 due to the UPR power threshold being too low, and can prevent the excessive suppression of the EV discharge power due to the UPR power threshold being too high. Also, the HEMS controller 100 can change the UPR power threshold according to the home power consumption measurement value by calculating the UPR power threshold target value. The manager of the HEMS 400 can set the ratio between the purchased grid power and the power supplied from the power source by setting the UPR coefficient.

  Hereinafter, modifications of the power threshold management process will be described.

  FIG. 12 shows a modification of the power threshold management process.

  In a variation of the power threshold management process, the HEMS controller 100 starts the result collection process at predetermined collection time intervals and starts the power threshold adjustment process at predetermined adjustment time intervals. The collection time is, for example, one minute, and the adjustment time is sufficiently longer than the collection time, for example, one week.

  When the results collection process is started, the HEMS controller 100 executes S110 and S120 as in the power threshold management process, and ends this flow.

  According to the above PCS performance collection process, the HEMS controller 100 can collect and store PCS performance information at collection time intervals.

  When the power threshold adjustment process is started, the HEMS controller 100 sets the measurement period from the previous power threshold adjustment process to the present time in S210b, and the PV generated power measurement value, the purchased system power measurement value, and the power sale in the measurement period. The power measurement value, the EV charge power measurement value, and the EV discharge power measurement value are acquired from the PCS performance information table. Thereafter, at S220, the HEMS controller 100 acquires the UPR power threshold, the UPR addition value, and the UPR subtraction value from the PCS power threshold table.

  Thereafter, in S310b, the HEMS controller 100 sets the power sale power measurement value as reverse flow power, and determines whether or not the maximum value of the reverse flow power within the measurement period is positive.

  If it is determined that the maximum value of the backward flow power is positive (S310b: Y), S320 and S410 are executed as in the power threshold management process, and this flow is ended.

  If it is determined that the maximum value of the reverse flow power is not positive (S310b: N), the HEMS controller 100 calculates a new UPR power threshold by subtracting the UPR subtraction value from the UPR power threshold in S350.

  After that, in S360 b, the HEMS controller 100 calculates the maximum value of the home power consumption measurement value in the measurement period, calculates the UPR power threshold target value based on the maximum value of the home power consumption measurement value, and the UPR power threshold is UPR. It is determined whether it is smaller than the power threshold target value. Here, the HEMS controller 100 calculates the UPR power threshold target value by multiplying the maximum value of the home power consumption measurement value by the UPR coefficient.

  When it is determined that the UPR power threshold is smaller than the UPR power threshold target value (S360b: Y), the HEMS controller 100 stores the UPR power threshold in the PCS 300 by transmitting the UPR power threshold to the PCS 300 in S410. End the flow

  According to the above power threshold adjustment process, the HEMS controller 100 can optimize the UPR power threshold based on the PCS performance information in the measurement period. Further, compared to the power threshold management process, this modification can reduce the load on the HEMS controller 100.

  When the UPR power threshold is changed by the power threshold management process or the power threshold adjustment process, the screen display unit 107 may cause the output unit 104 to display information indicating the change of the UPR power threshold. Thereby, the administrator can recognize the change of the UPR power threshold and the current UPR power threshold.

  According to the present embodiment, the HEMS controller 100 can change the UPR power threshold of the PCS 300 when the measured value of the power in the HEMS 400 satisfies the change condition. The first change condition is, for example, that there is no reverse flow and the UPR power threshold exceeds the UPR power threshold target value. The second change condition is, for example, that there is a reverse flow. In addition, by changing the UPR power threshold according to the measurement value, the HEMS controller 100 can suppress the output of the power supply and prevent the stop of the PCS 300. Further, by using the EV 16 and the PV as the power source, the EV 16 can be charged using the generated power of the PV 14, and the discharged power of the EV 16 can be supplied to the load 150. Thereby, purchase system power can be reduced and PV14 and EV16 can be used efficiently. In addition, the HEMS center 500 creates a charge / discharge plan, and the HEMS controller 100 controls the charge / discharge of the EV 16 based on the charge / discharge plan, so that the regional power supply and demand can be adjusted.

  The terms for the expression of the present invention will be explained. The HEMS 400 or the like may be used as the energy management system. The HEMS controller 100 or the like may be used as the power conversion control device. As a power converter, PCS300 etc. may be used. As a power supply, EV16, PV14, etc. may be used. PCS performance information etc. may be used as measurement information. As control information, PCS control information etc. may be used. A UPR power threshold or the like may be used as the first power threshold. An RPR power threshold or the like may be used as the second power threshold. The HEMS center 500 or the like may be used as the host control device. A charge / discharge power plan value or the like may be used as the storage battery control information. Charge / discharge plan information or the like may be used as the plan information. As a coefficient, a UPR coefficient or the like may be used. A communication network 510, a router 520, etc. may be used as the communication network.

14 ... PV 15 ... charge and discharge stand 16 ... EV 100 ... HEMS controller 101 ... CPU 103 ... input unit 104 ... output unit 109 ... communication unit 110 ... storage unit 150 ... load 300 ... PCS 410 ... distribution board 420 ... power meter 500 ... HEMS center 510 ... Communication network 520 ... Router 600 ... Power system

Claims (14)

It is connected to the power system and load via an AC power line, is connected to a power source via a DC power line, stores a first power threshold, and the power supplied from the power system to the load is equal to or higher than the first power threshold In some cases, a power conversion device that converts DC power from the DC power line into AC power and outputs the AC power to the AC power line,
It is connected to the power converter via a communication path, receives measurement information measured on the DC power line and the AC power line from the power converter, and determines whether the measurement information satisfies a change condition. A power conversion control device that generates control information instructing to change the first power threshold and transmits the control information to the power conversion device when it is determined that the measurement information satisfies the change condition;
Equipped with
The power converter changes a first power threshold stored in the power converter according to the control information.
Energy management system. The power conversion control device stores the first power threshold,
The power conversion control device calculates a target value of the first power threshold based on the measurement information, there is no reverse flow from the power conversion device to the power system, and the first power threshold is the target value. As the first change condition, it is determined whether or not the measurement information satisfies the first change condition, and when it is determined that the measurement information satisfies the first change condition, the first power threshold is Generating the control information instructing to decrease, and reducing a first power threshold stored in the power conversion control device based on the control information;
The energy management system according to claim 1. The power converter stores a second power threshold, and stops the conversion if the reverse flow exceeds the second power threshold.
The power conversion control device determines whether the measurement information satisfies the second change condition, with the reverse flow condition as a second change condition, and the measurement information satisfies the second change condition. When it is determined, the control information instructing to increase the first power threshold is generated, and the first power threshold stored in the power conversion control device is increased based on the control information.
The energy management system according to claim 2. The power conversion control device calculates the power consumption by the load based on the measurement information, and calculates the target value by multiplying the power consumption by a predetermined positive coefficient smaller than 1.
The energy management system according to claim 3. When the power conversion control device determines that the measurement information satisfies the first change condition, the power conversion control device subtracts the predetermined subtraction value from the first power threshold stored in the power conversion control device. An indication value of a first power threshold is calculated, the control information indicating the indication value is generated, and the first power threshold stored in the power conversion control device is replaced with the indication value.
The power converter replaces the first power threshold stored in the power converter according to the control information with the indication value.
The energy management system according to claim 4. When it is determined that the measurement information satisfies the second change condition, the power conversion control device adds the predetermined value to the first power threshold stored in the power conversion control device. Calculate the indicated value,
The energy management system according to claim 5. The power source includes a storage battery,
The power conversion control device generates storage battery control information indicating either charge power or discharge power of the storage battery, and transmits the storage battery control information to the power conversion device.
When the storage battery control information indicates the charging power, the power conversion device converts AC power from the AC power line into DC power and outputs the DC power line, and the storage battery control information indicates the discharging power. Converting DC power from the DC power line into AC power and outputting the AC power to the AC power line;
The energy management system according to any one of claims 1 to 6. The power source includes an electric vehicle incorporating the storage battery.
The energy management system according to claim 7. The power conversion control device is connected to a host control device through a communication network, receives from the host control device plan information indicating the plan of the charge power and the discharge power, and controls the storage battery based on the plan information Generate information,
The energy management system according to claim 8. The power conversion control device, when it is determined that the measurement information satisfies the change condition, causes the display device to display information indicating a change of the first power threshold value.
The energy management system according to any one of claims 1 to 9. The power source includes a photovoltaic device.
The energy management system according to any one of claims 1 to 10. The first power threshold is a UPR settling value,
An energy management system according to any one of the preceding claims. It is connected to the power system and load via an AC power line, is connected to a power source via a DC power line, stores a first power threshold, and the power supplied from the power system to the load is equal to or higher than the first power threshold In some cases, a power conversion apparatus that converts DC power from the DC power line into AC power and outputs the AC power to the AC power line is connected to the power converter through a communication path and measures the DC power line and the AC power line A communication unit that receives the measured information;
A calculation unit that determines whether the measurement information satisfies a change condition, and generates control information instructing change of the first power threshold when it is determined that the measurement information satisfies the change condition; ,
Equipped with
The communication unit transmits the control information to the power converter;
The first power threshold stored in the power converter is changed according to the control information.
Power conversion control device. It is connected to the power system and load via an AC power line, is connected to a power source via a DC power line, stores a first power threshold, and the power supplied from the power system to the load is equal to or higher than the first power threshold In some cases, the power conversion apparatus converts DC power from the DC power line into AC power and outputs the AC power to the AC power line, and receives measurement information measured on the DC power line and the AC power line,
It is determined whether the measurement information satisfies the change condition,
When it is determined that the measurement information satisfies the change condition, control information is generated that instructs to change the first power threshold,
A power conversion control method comprising: changing a first power threshold stored in the power converter according to the control information.

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