JP2014131413A - Power control device, power control method, program, and energy management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further simplify a control on a direct-current bus.SOLUTION: A power control device comprises: a direct-current bus serving as a path for supplying direct-current power; and plural power source apparatuses of inputting, outputting, or inputting/outputting the direct-current power to the direct-current bus. Then, it is judged whether each of the plural power source apparatuses serves as a control main body on the basis of a priority of the power source apparatus serving as a control main body for controlling a voltage of the direct-current bus to be constant, so as to determine a power source apparatus serving as a control main body. This technique can be applied, for example, to a power control device in which plural power source apparatuses are connected to the direct-current bus.

Description

  The present disclosure relates to a power control device, a power control method, a program, and an energy management system, and in particular, a power control device, a power control method, a program, and energy management that can more easily control a DC bus. About the system.

  Conventionally, in order to efficiently use not only the power from the power system that supplies commercial power but also the power supplied from multiple power sources, such as the power generated by solar power generation and the power stored in the battery An energy management system that performs optimal power management has been developed.

  For example, Patent Document 1 discloses a system that can stably use power even when a power failure occurs.

  In the future, considering that energy conversion systems will promote higher conversion efficiency, smaller systems, and lower costs, multiple devices such as batteries and PV (Photovoltaics) will be used in the future. Is assumed to be connected to a DC (Direct Current) bus serving as a path for supplying DC power.

  FIG. 1 shows a configuration example of the energy management system.

  As shown in FIG. 1, in the energy management system 11, a power control device 12 is connected to a power system 14 via an ammeter 13, and a PV 15, a battery 16, and an AC (Alternating Current) load 17 are connected to the power control device 12. Are connected and configured.

  The power control device 12 includes an AC / DC conversion unit 21, a PV DC / DC conversion unit 22, a battery DC / DC conversion unit 23, and a control unit 24. The AC terminal of the AC / DC converter 21 is connected to the power system 14 and the AC load 17. On the other hand, the DC-side terminal of the AC / DC converter 21 is connected to the PV 15 via the PV DC / DC converter 22 and to the battery 16 via the battery DC / DC converter 23. . Here, the wiring connected to the DC side terminal of the AC / DC conversion unit 21 and supplying DC power between the PV DC / DC conversion unit 22 and the battery DC / DC conversion unit 23 is as follows. This will be referred to as a DC bus 25 as appropriate.

The control unit 24 controls the AC / DC conversion unit 21, the PV DC / DC conversion unit 22, and the battery DC / DC conversion unit 23 according to the state of the energy management system 11.
For example, the operation mode of the energy management system 11 includes a self-sufficient operation mode in which power management is performed without depending on power supplied from the power system 14 as much as possible, and the control unit 24 performs control according to the operation mode. I do. Moreover, the control part 24 is in the self-sufficiency operation mode, the electric power state of the energy management system 11 (For example, the grid connection which is a state which can supply electric power to the energy management system 11 from the electric power system 14, or a power failure is carried out. Control is performed according to the self-sustained operation in a state where power cannot be supplied from the power system 14 to the energy management system 11 by being generated.

  With reference to FIG. 2, the power supply path in the self-sufficient operation mode will be described. In addition, illustration of the control part 24 is abbreviate | omitted in FIG.

  At the normal time of self-sufficiency operation mode (at the time of grid connection and non-full charge), the power generated by the PV 15 is DC / DC converted by the PV DC / DC converter 22 as shown in FIG. 2A. The voltage is supplied to the AC / DC converter 21 and the battery DC / DC converter 23 via the DC bus 25. Then, the power AC / DC converted by the AC / DC converter 21 is supplied to the AC load 17, and the battery 16 is charged with the power DC / DC converted by the battery DC / DC converter 23.

  At this time, the control unit 24 controls the AC / DC conversion unit 21 so as to output power following the power consumption of the AC load 17. Further, the control unit 24 controls the PV DC / DC conversion unit 22 so as to output power in accordance with MPPT (Maximum. Power Point Tracker) control for extracting power from the PV 15 at the output voltage that is the maximum power. Then, the control unit 24 performs charging control so that the voltage of the DC bus 25 becomes constant (that is, charging is performed when the voltage of the DC bus 25 is high, and discharging is performed when the voltage of the DC bus 25 is low). Control is performed on the battery DC / DC converter 23. Therefore, for example, when the PV 15 is generating 4 kW and the power consumption of the AC load 17 is 1 kW, the battery 16 is charged with 3 kW.

  In addition, when the battery 16 is fully charged (SOC (state of charge) = 100%) in the self-sufficient operation mode during grid connection, the battery DC / DC conversion unit 23 cannot charge the battery 16. . In this case, as shown in FIG. 2B, the power generated by the PV 15 is DC / DC converted by the PV DC / DC converter 22 and supplied to the AC / DC converter 21 via the DC bus 25. AC / DC converted by the / DC converter 21 and supplied to the AC load 17, and surplus power is reversely flowed to the power system 14.

  At this time, the control unit 24 controls the PV DC / DC conversion unit 22 so as to output electric power according to the MPPT control. In addition, the control unit 24 controls the AC / DC conversion unit 21 so as to perform output control so that the voltage of the DC bus 25 becomes constant (that is, control for surplus power to flow backward to the power system 14). . Also, the battery DC / DC converter 23 is in a stopped state. Therefore, for example, when the PV 15 is generating 4 kW and the power consumption of the AC load 17 is 1 kW, 3 kW of power is reversely flowed through the power system 14.

  Furthermore, when a power failure occurs when the battery 16 is fully charged (SOC = 100%) and the self-sufficiency operation mode during self-sustained operation is entered, charging of the battery 16 and reverse power flow to the power system 14 may be performed. become unable. In this case, as shown in FIG. 2C, the power generated by the PV 15 is DC / DC converted by the PV DC / DC converter 22 and supplied to the AC / DC converter 21 via the DC bus 25. AC / DC converted by the / DC converter 21 and supplied to the AC load 17.

  At this time, the control unit 24 performs output control so that the voltage of the DC bus 25 becomes constant (that is, control using the output of the PV 15 in accordance with the AC load 17). Control over. Further, the AC / DC converter 21 outputs power following the power consumption of the AC load 17, and the battery DC / DC converter 23 is in a stopped state. Therefore, for example, when the power consumption of the AC load 17 is 1 kW, control is performed such that the PV 15 generates 1 kW.

  As described above, the control unit 24 determines whether the AC / DC conversion unit 21, PV use is based on the power state of the energy management system 11, the power generation state of the PV 15, the charging state of the battery 16, the power consumption state of the AC load 17, and the like. The control contents for the DC / DC converter 22 and the battery DC / DC converter 23 are selected. At that time, any one of the AC / DC conversion unit 21, the PV DC / DC conversion unit 22, and the battery DC / DC conversion unit 23 is controlled to control the voltage of the DC bus 25 to be constant ( Hereinafter, the control contents are set so as to perform DC bus voltage control as appropriate.

  FIG. 3 shows the control content selected by the control unit 24.

  For example, when the power state of the energy management system 11 is grid connection, the power generation state of the PV 15 is generating power, and the charge state of the battery 16 is chargeable / dischargeable, the control unit 24 performs the first control. Select content. In the first control content, the battery DC / DC converter 23 performs DC bus voltage control, and the AC / DC converter 21 performs output control to output power to the AC load 17 so as not to reversely flow to the power system 14. The battery DC / DC conversion unit 23 is set to perform MPPT control.

  Further, for example, the power state of the energy management system 11 is during grid connection, the power generation state of the PV 15 is generating power, the charge state of the battery 16 cannot be charged, and the power consumption state of the AC load 17 is PV 15. When the power generation amount is equal to or less than the power generation amount, the control unit 24 selects the second control content. In the second control content, the AC / DC converter 21 performs DC bus voltage control, the battery DC / DC converter 23 performs MPPT control, and the battery DC / DC converter 23 is set to stop. ing.

  Hereinafter, as shown in FIG. 3, in the self-sufficient operation mode, the control unit 24 operates in accordance with the power state of the energy management system 11, the power generation state of the PV 15, the charge state of the battery 16, and the power consumption state of the AC load 17. The thirteenth control content can be selected from the three control details.

  FIG. 4 and FIG. 5 show flowcharts in which the control unit 24 executes processing for selecting the control content. FIG. 4 shows a flowchart in the case where the power state of the energy management system 11 is during grid connection, and FIG. 5 shows a flowchart in the case where the power state of the energy management system 11 is during autonomous operation. It is shown.

  As shown in FIG. 4, when the power state of the energy management system 11 is grid connection, in step S11, the control unit 24 determines whether or not the power generation state of the PV 15 is generating power, and the power generation of the PV 15 is performed. If it is determined that the state is generating power, the process proceeds to step S12. In step S <b> 12, the control unit 24 determines whether the charging state of the battery 16 is chargeable / dischargeable, chargeable, or not dischargeable.

  In step S12, when the control unit 24 determines that the state of charge of the battery 16 is chargeable / dischargeable, the process proceeds to step S13. In step S <b> 13, the control unit 24 controls the AC load so that the battery DC / DC conversion unit 23 performs DC bus voltage control (surplus charging and insufficient discharge) and the AC / DC conversion unit 21 does not reversely flow into the power system 14. The output control (maximum discharge when the power is insufficient) is performed in 17 and the PV DC / DC conversion unit 22 selects the first control content to perform the MPPT control, and the process ends.

  On the other hand, when the control unit 24 determines in step S12 that the charge state of the battery 16 is not chargeable, the process proceeds to step S14, and the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount. It is determined whether or not there is.

  In step S14, when the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount, the process proceeds to step S15. In step S15, the control unit 24 performs DC bus voltage control (the surplus power is reverse flow to the power system 14), the PV DC / DC conversion unit 22 performs MPPT control, and the AC / DC conversion unit 21 performs battery power control. The second control content to be stopped by the DC / DC converter 23 is selected, and the process is terminated.

  On the other hand, when the control unit 24 determines in step S14 that the power consumption state of the AC load 17 is not less than or equal to the power generation amount (greater than the power generation amount), the process proceeds to step S16. In step S <b> 16, the control unit 24 performs DC bus voltage control (insufficient discharge) by the battery DC / DC conversion unit 23, and the AC / DC conversion unit 21 supplies power to the AC load 17 so as not to flow backward to the power system 14. Is output, the PV DC / DC conversion unit 22 selects the third control content for performing the MPPT control, and the process ends.

  Furthermore, in step S12, when the control unit 24 determines that the state of charge of the battery 16 is not dischargeable, the process proceeds to step S17, and the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount. It is determined whether or not there is.

  In step S17, when the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount, the process proceeds to step S18. In step S <b> 18, the control unit 24 performs DC bus voltage control (surplus charging) by the battery DC / DC conversion unit 23, and the AC / DC conversion unit 21 supplies power to the AC load 17 so as not to flow backward to the power system 14. Is output, the PV DC / DC conversion unit 22 selects the fourth control content for performing the MPPT control, and the process is terminated.

  On the other hand, when the control unit 24 determines in step S17 that the power consumption state of the AC load 17 is not less than or equal to the power generation amount (greater than the power generation amount), the process proceeds to step S19. In step S19, the control unit 24 performs DC bus voltage control (the insufficient power is supplemented from the power system 14) by the AC / DC conversion unit 21, the PV DC / DC conversion unit 22 performs MPPT control, and the battery DC The fifth control content to be stopped by the / DC converter 23 is selected, and the process is terminated.

  Moreover, in step S11, when the control part 24 determines with the electric power generation state of PV15 not generating electric power, a process progresses to step S20. In step S <b> 20, the control unit 24 determines whether the state of charge of the battery 16 is unchargeable or undischargeable.

  In step S20, when the control unit 24 determines that the state of charge of the battery 16 is not chargeable, the process proceeds to step S21. In step S <b> 21, the control unit 24 controls the AC load 17 so that the battery DC / DC conversion unit 23 performs DC bus voltage control (load following discharge) and the AC / DC conversion unit 21 does not reversely flow into the power system 14. Output control for outputting electric power (maximum discharge when electric power is insufficient) is performed, and the sixth control content in which the PV DC / DC conversion unit 22 is stopped is selected, and the process ends.

  On the other hand, when the control unit 24 determines in step S20 that the charge state of the battery 16 is not dischargeable, the process proceeds to step S22, and the control unit 24 determines whether or not the battery 16 needs to be charged. Determine whether.

  In step S22, when the control unit 24 determines that it is necessary to charge the battery 16, the process proceeds to step S23. In step S23, in the control unit 24, the AC / DC conversion unit 21 performs DC bus voltage control, the PV DC / DC conversion unit 22 is stopped, and the battery DC / DC conversion unit 23 is CPCV (constant power-constant). The seventh control content to be charged is selected according to the voltage (Constant Power-Constant Voltage) control, and the process is terminated.

  On the other hand, when the control unit 24 determines in step S22 that it is not necessary to charge the battery 16, the process proceeds to step S24. In step S24, the control unit 24 selects to stop the operation of the AC / DC conversion unit 21, the PV DC / DC conversion unit 22, and the battery DC / DC conversion unit 23, and the process is ended.

  Moreover, when the electric power state of the energy management system 11 is at the time of a self-sustained operation, as shown in FIG. 5, in step S31, the control unit 24 determines whether or not the power generation state of the PV 15 is generating power. If it is determined that the power generation state is generating power, the process proceeds to step S32. In step S32, the control unit 24 determines whether the state of charge of the battery 16 is chargeable / dischargeable, not chargeable, or not dischargeable.

  In step S32, when the control unit 24 determines that the state of charge of the battery 16 is chargeable / dischargeable, the process proceeds to step S33. In step S33, the control unit 24 controls the battery DC / DC conversion unit 23 to perform DC bus voltage control (excessive charge and insufficient discharge), and the AC / DC conversion unit 21 makes the AC voltage of the self-sustained output constant. Output control for outputting electric power is performed, and the PV DC / DC conversion unit 22 selects the eighth control content for performing MPPT control, and the process ends.

  On the other hand, when the control unit 24 determines in step S32 that the charging state of the battery 16 is not chargeable, the process proceeds to step S34, and the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount. It is determined whether or not there is.

  In step S34, when the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount, the process proceeds to step S35. In step S35, the control unit 24 performs DC bus voltage control (output limitation) by the PV DC / DC conversion unit 22, and the AC / DC conversion unit 21 outputs power so that the AC voltage of the independent output is constant. The output control is performed, the ninth control content for the battery DC / DC conversion unit 23 to stop is selected, and the process ends.

  On the other hand, when the control unit 24 determines in step S34 that the power consumption state of the AC load 17 is not less than or equal to the power generation amount (greater than the power generation amount), the process proceeds to step S36. In step S36, the control unit 24 controls the battery DC / DC conversion unit 23 to perform DC bus voltage control (insufficient discharge), and the AC / DC conversion unit 21 outputs power so that the AC voltage of the independent output is constant. The PV DC / DC conversion unit 22 selects the tenth control content for performing the MPPT control, and the process ends.

  Furthermore, when the control unit 24 determines in step S32 that the state of charge of the battery 16 is not dischargeable, the process proceeds to step S37, and the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount. It is determined whether or not there is.

  In step S37, when the control unit 24 determines that the power consumption state of the AC load 17 is equal to or less than the power generation amount, the process proceeds to step S38. In step S38, the control unit 24 performs DC bus voltage control (surplus charging) by the battery DC / DC conversion unit 23, and the AC / DC conversion unit 21 outputs power so that the AC voltage of the independent output is constant. The PV DC / DC conversion unit 22 selects the eleventh control content for performing the MPPT control, and the process ends.

  On the other hand, when the control unit 24 determines in step S37 that the power consumption state of the AC load 17 is not less than or equal to the power generation amount (greater than the power generation amount), the process proceeds to step S39. In step S39, the control unit 24 determines, for example, a control for the AC / DC conversion unit 21, the PV DC / DC conversion unit 22, and the battery DC / DC conversion unit 23 according to a higher order instruction. The content is selected and the process is terminated.

  Moreover, in step S31, when the control part 24 determines with the electric power generation state of PV15 not generating electric power, a process progresses to step S40. In step S40, the control unit 24 determines whether the state of charge of the battery 16 is unchargeable or undischargeable.

  In step S40, when the control unit 24 determines that the state of charge of the battery 16 is not chargeable, the process proceeds to step S41. In step S41, the control unit 24 controls the battery DC / DC conversion unit 23 to perform DC bus voltage control (load following discharge), and the AC / DC conversion unit 21 supplies power so that the AC voltage of the independent output is constant. The thirteenth control content for performing output control is selected, and the process ends.

  On the other hand, when the control unit 24 determines in step S40 that the state of charge of the battery 16 is not dischargeable, the process proceeds to step S42. In step S42, the control unit 24 selects to stop the operation of the AC / DC conversion unit 21, the PV DC / DC conversion unit 22, and the battery DC / DC conversion unit 23, and the process is ended.

  As described above, in the conventional energy management system 11, the control unit 24 performs DC bus voltage control by selecting a control content by dividing the case according to the conditions shown in FIG. 4 and FIG. The controlling subject was determined.

JP 2011-135763 A

  By the way, in the configuration in which a plurality of power sources are connected to the DC bus 25 as described above, when the voltage of the DC bus 25 is controlled by a plurality of control entities, hunting or the like occurs due to interference between these controls. Since there is a possibility, basically, it is desirable to have one control entity. However, since it is necessary to change the control subject of the DC bus 25 according to the state of the energy management system 11, the process by which the control unit 24 selects the control content is complicated.

  In the future, it is assumed that the types and number of devices connected to the DC bus 25 will increase. In that case, the case division in the process of selecting the control content by the control unit 24 increases exponentially, and the process of selecting the control content by the control unit 24 may be complicated and complicated.

  Furthermore, it is assumed that the order of the case classification as described above is changed, or the number of devices connected to the DC bus 25 is increased or reduced. In order to cope with such a change, it is difficult for the control unit 24 to change the process of selecting the control content (re-creating the control algorithm), and it is assumed that much labor is required.

  This indication is made in view of such a situation, and makes it possible to simplify control to a direct-current bus.

  A power control device according to one aspect of the present disclosure includes a DC bus serving as a path for supplying DC power, an output of DC power connected to the DC bus, and output of DC power from the DC bus. A plurality of power supply devices that perform at least one of inputs, and for each of the plurality of power supply devices, based on the priority order of the power supply device that is a control body that controls the voltage of the DC bus to be constant, The power supply device to be a control subject is determined.

  A power control method or program according to an aspect of the present disclosure includes a direct current bus serving as a path for supplying direct current power, an output of direct current power to the direct current bus, and direct current from the direct current bus. A power control method of a power control device including a plurality of power supply devices that perform at least one of input of power, or a program executed by a computer that controls the power control device, for each of the plurality of power supply devices, The method includes a step of determining the power supply device to be the control entity based on the priority order of the power supply device to be the control entity that controls the DC bus voltage to be constant.

  In one aspect of the present disclosure, for each of a plurality of power supply devices, the power supply device that is a control entity is determined based on the priority order of the power supply device that is a control entity that controls the DC bus voltage to be constant. .

  According to one aspect of the present disclosure, it is possible to further simplify control of the DC bus.

It is a block diagram which shows the example of 1 structure of an energy management system. It is a figure which shows the electric power supply path | route in independent operation mode. It is a figure which shows the control content selected with an electric power control apparatus. It is a flowchart which performs the process which selects the control content in the case of grid connection. It is a flowchart which performs the process which selects the control content in the case of self-sustained operation. It is a block diagram showing an example of composition of an embodiment of an energy management system to which this art is applied. It is a figure which shows the simple structural example of an energy management system. It is a figure explaining the relationship between a priority and a control main body. It is a flowchart of the process which determines the control main body which performs DC bus voltage control which the DC / DC conversion part for batteries performs. It is a flowchart explaining a control subject determination process. It is a flowchart of the process which determines the control main body which performs DC bus voltage control which an AC / DC conversion part performs. It is a flowchart of the process which determines the control main body which performs DC bus voltage control which DC / DC conversion part for PV performs. It is a figure which shows the simple structural example of the energy management system to which EV and DC load were connected. It is a figure which shows the structural example of the contact for notifying whether DC bus voltage control can be performed. It is a block diagram which shows the structural example of an energy management system. It is a flowchart explaining the process which maintains the state which always supplies electric power with respect to DC bus. It is a block diagram which shows the 1st modification of an energy management system. It is a block diagram which shows the 2nd modification of an energy management system.

  Hereinafter, specific embodiments to which the present technology is applied will be described in detail with reference to the drawings.

  FIG. 6 is a block diagram illustrating a configuration example of an embodiment of an energy management system to which the present technology is applied.

  6, the energy management system 31 includes a power control device 32 connected to a power system 34 via an ammeter 33, a PV 35, a battery 36, an EV (Electric Vehicle) 37, an AC load 38, and a DC load 39−. 1 and 39-2 are connected to the power control device 32.

  The power control device 32 supplies power supplied from a plurality of power sources (power system 34, PV 35, battery 36, or EV 37) connected to the power control device 32 to a plurality of loads ( The control which supplies to AC load 38 and DC load 39-1 and 39-2) is performed.

  The ammeter 33 measures the power supplied from the power system 34 to the power control device 32 and the power supplied from the power control device 32 to the power system 34 (reverse power flow). The power system 34 supplies AC power to the energy management system 31.

  For example, the PV 35 is configured in a panel shape by connecting a plurality of solar cell modules, generates power according to the amount of received sunlight, and supplies the generated power to the power control device 32. The battery 36 stores the power supplied from the power control device 32 or supplies the stored power to the power control device 32. The EV 37 is appropriately connected to the power control device 32 according to the use of the EV 37 by the user, and incorporates a battery that stores the power supplied from the power control device 32.

  The AC load 38 is a device that consumes AC power and is driven, and the DC loads 39-1 and 39-2 are devices that consume and drive DC power. In the configuration example of FIG. 6, two DC loads 39-1 and 39-2 are connected to the power control device 32, but the number of the DC loads 39-1 and 39-2 can be increased or decreased.

  The power controller 32 includes an AC / DC converter 41, a PV DC / DC converter 42, a battery DC / DC converter 43, an EV DC / DC converter 44, and a load DC / DC converter 45-1. And 45-2, a distribution board 46, and a system control unit 47. Also, the distribution board 46 houses breakers 51-1 to 51-6, ammeters 52-1 to 52-4, and a DC bus 53.

  In the power control device 32, the AC side terminal of the AC / DC conversion unit 41 is connected to the power line 40 that connects the power system 34 and the AC load 38, and the DC side terminal of the AC / DC conversion unit 41 is Via the breaker 51-1, it is connected to a DC bus 53 which is a path for supplying DC power. The PV DC / DC converter 42 to which the PV 35 is connected is connected to the DC bus 53 via the breaker 51-2. Similarly, the battery DC / DC converter 43 to which the battery 36 is connected is connected to the DC bus 53 via the breaker 51-3, and the EV DC / DC converter 44 to which the EV 37 is connected is the breaker 51-4. And connected to the DC bus 53 via the ammeter 52-1.

  Also, the load DC / DC converter 45-1 to which the DC load 39-1 is connected is connected to the DC bus 53 via the breaker 51-5 and the ammeter 52-2, and the DC load 39-2 is connected. The load DC / DC conversion unit 45-2 is connected to the DC bus 53 via the breaker 51-6 and the ammeter 52-3. The AC load 38 is connected to the AC / DC conversion unit 41 via the breaker 51-7 and the ammeter 52-4.

  The AC / DC conversion unit 41 outputs DC power obtained by AC / DC converting AC power supplied from the power system 34 to the DC bus 53. Further, the AC / DC conversion unit 41 performs DC / AC conversion on the DC power supplied via the DC bus 53 and supplies it to the AC load 38 via the power line 40 or reversely flows to the power system 34. To do.

  The PV DC / DC conversion unit 42 performs DC / DC conversion (step-up / step-down) so that the electric power generated in the PV 35 becomes a predetermined voltage, and outputs it to the DC bus 53. For example, the PV DC / DC converter 42 can perform MPPT control for tracking the maximum output point so as to extract the maximum power from the PV 35.

  The battery DC / DC conversion unit 43 performs DC / DC conversion (step-up / step-down) on the electric power stored in the battery 36 and outputs it to the DC bus 53, or converts the electric power supplied via the DC bus 53 to DC / DC. The battery 36 is charged by DC conversion.

  When the EV 37 is connected to the power control device 32, the EV DC / DC conversion unit 44 DC / DC converts the electric power stored in the EV 37 and outputs it to the DC bus 53 or via the DC bus 53. The electric power supplied is DC / DC converted to charge the EV 37.

  The load DC / DC converters 45-1 and 45-2 convert the electric power supplied via the DC bus 53 into voltages necessary for driving the DC loads 39-1 and 39-2 connected thereto, respectively. DC / DC conversion is performed and supplied to DC loads 39-1 and 39-2, respectively.

  The system control unit 47 configures the power control device 32 based on, for example, the current measured by the ammeter 33 and the ammeters 52-1 to 52-4, the power generation state of the PV 35, the charge state of the battery 36, and the like. Control each block. Thereby, the system control part 47 controls the energy management system 31 whole. In FIG. 6, illustration of wirings that connect the system control unit 47 and each block is omitted.

  In the system control unit 47, in the energy management system 31, the priority order of the devices that are the control entities that perform DC bus voltage control is set in advance so that the voltage of the DC bus 53 is constant. And in the energy management system 31, the process for determining the control main body which performs DC bus voltage control separately for every apparatus which can become a control main body is performed.

  Here, in order to simplify description, it demonstrates using the structural example of the energy management system 31 as shown in FIG.

  As shown in FIG. 7, in the configuration in which the power system 34, PV 35, battery 36, and AC load 38 are connected to the power control device 32, for example, the priority order of the battery DC / DC conversion unit 43 is the highest. The priority of the AC / DC converter 41 is set to the second priority, and the priority of the PV DC / DC converter 42 is set to the third priority. In addition, this priority order is preset in the system control unit 47, for example, and can be exchanged according to an instruction from a higher-level device (not shown), for example.

  By setting such priorities, the battery DC / DC converter 43 having the highest priority basically performs DC bus voltage control. If the battery DC / DC converter 43 cannot perform DC bus voltage control due to the state of the battery 36 or a higher-level instruction, as shown in FIG. 8A, the control entity that performs DC bus voltage control is The priority is shifted to the second AC / DC conversion unit 41.

  Furthermore, when the AC / DC conversion unit 41 cannot perform DC bus voltage control, the control entity that performs DC bus voltage control has the third highest priority DC / DC for PV as shown in FIG. 8B. The conversion unit 42 is moved to. In addition, when other devices that can be a control entity that performs DC bus voltage control are connected and the priority of the device is lower than that of the PV DC / DC conversion unit 42, the PV DC / DC conversion unit 42 When it becomes impossible to perform the DC bus voltage control, the control subject that performs the DC bus voltage control moves to a lower-level device.

  That is, as shown in FIG. 8, a device that can be a control entity determines that a device having a higher priority than the device itself cannot perform DC bus voltage control. On the other hand, when a device that can be a control subject cannot perform DC bus voltage control by a device having a higher priority than the device itself, and the device itself can perform DC bus voltage control. And decide to become the controlling entity.

  In addition, the priority order of the control subject that performs DC bus voltage control is set such that, for example, a device that wants to use the power to the maximum extent effectively has a lower priority order. For example, in the configuration shown in FIG. 7, the power generated by the PV 35 is used to the maximum, and the AC / DC converter 41 matches the power consumption of the AC load 38, the power generation state of the PV 35, the charging state of the battery 36, etc. It is desirable that the battery 36 be used in a buffering role such that the surplus power is charged or discharged when the power is insufficient. Therefore, in the effective utilization degree, the order is the DC / DC conversion unit for PV 42, the AC / DC conversion unit 41, and the DC / DC conversion unit 43 for battery. Accordingly, it is preferable that the priority order of the control subject performing the DC bus voltage control is the order of the battery DC / DC conversion unit 43, the AC / DC conversion unit 41, and the PV DC / DC conversion unit 42. .

  In the power control device 32, the process for determining the control subject that performs the DC bus voltage control is not performed by the system control unit 47, but the AC / DC conversion unit 41, the PV DC / DC conversion unit 42, And it is performed individually in the DC / DC converter 43 for battery.

  Next, referring to FIG. 9 to FIG. 12, control for performing DC bus voltage control individually performed in the AC / DC converter 41, the PV DC / DC converter 42, and the battery DC / DC converter 43. Processing for determining the subject will be described.

  For example, in the energy management system 31, when the priority of a control subject that performs DC bus voltage control is changed, when the power state of the energy management system 31 is switched, or control that performs DC bus voltage control When the main body cannot perform the DC bus voltage control, a process of determining a control main body that performs the DC bus voltage control is started. Further, in the following description, the priority order of the control entity that performs DC bus voltage control is such that the priority order of the battery DC / DC conversion unit 43 is the highest priority and the priority order of the AC / DC conversion unit 41 is 2. It is assumed that the priority of the PV DC / DC converter 42 is set as the third.

  FIG. 9 shows a flowchart of processing for determining a control subject that performs DC bus voltage control executed by the battery DC / DC converter 43.

  In step S <b> 51, the battery DC / DC conversion unit 43 determines whether the power state of the energy management system 11 is during grid connection or during independent operation.

  In step S51, when the battery DC / DC conversion unit 43 determines that the power state of the energy management system 11 is grid connection, the process proceeds to step S52. In step S52, the battery DC / DC conversion unit 43 acquires priority order information in which the priority order of the device that is the control entity that performs DC bus voltage control is set. For example, the priority order information is stored in the memory of the system control unit 47, and the battery DC / DC conversion unit 43 acquires the priority order information from the memory by communicating with the system control unit 47.

  In step S <b> 53, the battery DC / DC converter 43 performs a control body determination process for determining whether the battery DC / DC converter 43 itself is a control body that performs DC bus voltage control. The control subject determination process will be described later with reference to FIG.

  In step S54, the battery DC / DC conversion unit 43 determines whether or not it performs DC bus voltage control based on the processing result of the control subject determination process in step S53.

  In step S54, if the battery DC / DC conversion unit 43 determines that it performs DC bus voltage control, the process proceeds to step S55. In step S55, the battery DC / DC converter 43 starts the DC bus voltage control, the control is performed so that the voltage of the DC bus 53 becomes constant, and the process of determining the control subject ends.

  On the other hand, if the battery DC / DC conversion unit 43 determines in step S54 that it does not perform DC bus voltage control, the process proceeds to step S56. In step S56, the battery DC / DC conversion unit 43 selects the stop of the operation or the start of charging of the battery 36 according to the CPCV control in accordance with the upper instruction, and the process of determining the control subject is ended. .

  Moreover, in step S51, when the battery DC / DC conversion unit 43 determines that the power state of the energy management system 11 is in a self-sustaining operation, the process proceeds to step S57. In step S57, the battery DC / DC conversion unit 43 acquires priority order information in the same manner as in step S52.

  In step S58, the control subject determination process is performed in the same manner as in step S53, and in step S59, the battery DC / DC converter 43 itself determines the DC bus voltage based on the processing result of the control subject determination process in step S58. It is determined whether to perform control.

  In step S59, if the battery DC / DC conversion unit 43 determines that it performs DC bus voltage control, the process proceeds to step S60. In step S60, the battery DC / DC converter 43 starts the DC bus voltage control, the control is performed so that the voltage of the DC bus 53 becomes constant, and the process of determining the control subject ends.

  On the other hand, if the battery DC / DC conversion unit 43 determines in step S59 that it does not perform DC bus voltage control, the process proceeds to step S61, and the battery DC / DC conversion unit 43 stops operating. The process for determining the control subject is terminated.

  Next, FIG. 10 is a flowchart for explaining the control subject determination process performed in steps S53 and S58 of FIG.

  In step S71, the battery DC / DC converter 43 determines whether the priority of the battery DC / DC converter 43 itself is highest based on the priority information acquired in step S52 or S57 of FIG. Determine whether.

  In step S71, when the battery DC / DC conversion unit 43 determines that the priority of the battery DC / DC conversion unit 43 itself is the highest priority, the process proceeds to step S72, and the battery DC / DC conversion unit 43 It is determined whether or not 43 itself can perform DC bus voltage control. For example, the battery DC / DC conversion unit 43 determines whether or not the DC bus voltage control can be performed based on the state of charge of the battery 36 or an upper instruction.

  Specifically, the battery DC / DC conversion unit 43 is not able to be charged because the SOC of the battery 36 is 100%, or when the battery is instructed by the host to forcibly charge. It is determined that the DC bus voltage control cannot be performed. Alternatively, as a result of the DC / DC conversion unit 43 for battery trying to control the DC bus voltage, for example, the voltage of the DC bus 53 must be controlled to 370V, but the voltage of the DC bus 53 is increased to 380V. On the other hand, if the voltage is lowered to 360 V, it is determined that the DC bus voltage cannot be controlled because the voltage of the DC bus 53 is in an uncontrollable state.

  In step S72, when the battery DC / DC conversion unit 43 determines that the DC bus voltage control can be performed, the process proceeds to step S73, and the battery DC / DC conversion unit 43 performs the control subject determination process. As a determination result, it is determined that DC bus voltage control is performed. In step S74, the battery DC / DC conversion unit 43 obtains control availability information indicating that the DC bus voltage control can be performed, as to the lower priority device (in this case, the AC / DC conversion unit 41 and the PV DC / DC converter 42), and the control subject determination process is terminated.

  On the other hand, when the battery DC / DC conversion unit 43 determines in step S72 that the DC bus voltage control cannot be performed, the process proceeds to step S75, and the battery DC / DC conversion unit 43 determines whether the control subject is determined. As a determination result in the processing, it is determined that the DC bus voltage control is not performed. In step S76, the battery DC / DC converter 43 supplies control availability information indicating that the DC bus voltage control cannot be performed to the lower priority device, and the control subject determination process is terminated. The

  In step S71, when the battery DC / DC conversion unit 43 determines that the priority of the battery DC / DC conversion unit 43 is not the highest priority, the process proceeds to step S77. In step S <b> 77, the battery DC / DC conversion unit 43 acquires control availability information of a device having a higher priority than the battery DC / DC conversion unit 43. For example, the AC / DC conversion unit 41 and the PV DC / DC conversion unit 42 perform the same processing as the battery DC / DC conversion unit 43. If the AC / DC conversion unit 41 or the PV DC / DC conversion unit 42 has a higher priority than the battery DC / DC conversion unit 43, the processing of step S74 or S76 described above in those devices is performed. As a result, control availability information is transmitted. In response to this, the battery DC / DC conversion unit 43 acquires the control availability information in step S77.

  In step S78, the battery DC / DC conversion unit 43 determines whether or not a higher-priority device can perform DC bus voltage control according to the control availability information acquired in step S77. If it is determined in step S78 that the higher priority device cannot perform DC bus voltage control, the process proceeds to step S72, and the higher priority device can perform DC bus voltage control. If it is determined, the process proceeds to step S75. Thereafter, the above-described processing is performed.

  Next, FIG. 11 shows a flowchart of a process for determining a control entity that performs DC bus voltage control executed by the AC / DC converter 41.

  In step S <b> 81, the AC / DC conversion unit 41 determines whether the power state of the energy management system 11 is during grid interconnection or during independent operation. And when it determines with the electric power state of the energy management system 11 being at the time of grid connection, AC / DC conversion part 41 acquires priority order information in step S82, Then, a control subject judgment process (FIG. 10).

  In step S84, the AC / DC converter 41 determines whether or not it performs DC bus voltage control. If it is determined that it performs DC bus voltage control, the DC bus voltage is determined in step S85. Control is started and the process is terminated. On the other hand, if it is determined in step S84 that it does not perform DC bus voltage control, the process proceeds to step S86, and the AC / DC converter 41 outputs power following the power consumption of the AC load 38. The control is started, and the process is terminated.

  On the other hand, in Step S81, when it is determined that the power state of the energy management system 11 is in the independent operation, the process proceeds to Step S87. Then, the AC / DC converter 41 performs the same processing as in steps S82 to S86 in steps S87 to S91.

  Next, FIG. 12 shows a flowchart of a process for determining a control subject that performs DC bus voltage control executed by the PV DC / DC converter 42.

  In step S101, the DC / DC conversion unit for PV 42 determines whether the power state of the energy management system 11 is during grid connection or during independent operation. And when it determines with the electric power state of the energy management system 11 being at the time of grid connection, the DC / DC conversion part 42 for PV acquires priority order information in step S102, Then, a control subject judgment process in step S103 (FIG. 10) is performed.

  Then, in step S104, the PV DC / DC conversion unit 42 determines whether or not it performs DC bus voltage control. If it is determined that it performs DC bus voltage control, the DC DC / DC conversion unit 42 performs DC bus control in step S105. The bus voltage control is started and the process is terminated. On the other hand, if it is determined in step S104 that it does not perform DC bus voltage control, the process proceeds to step S106, the PV DC / DC converter 42 starts MPPT control, and the process ends. The When the PV 35 is not generating power, the PV DC / DC converter 42 stops operating in step S106.

  On the other hand, in step S101, when it is determined that the power state of the energy management system 11 is in a self-sustaining operation, the process proceeds to step S107. Then, the DC / DC converter for PV 42 performs the same processes as steps S102 to S106 in steps S107 to S111.

  As described above, in the energy management system 31, the AC / DC conversion unit 41, the PV DC / DC conversion unit 42, and the battery DC / DC conversion unit 43 are individually controlled by a control entity that performs DC bus voltage control. It can be determined whether or not. As a result, for example, the system control unit 47 can construct a control program more easily than the process of determining a device to be a control entity that performs DC bus voltage control. In addition, while the conventional control method determines the operation of the device (the control entity that performs DC bus voltage control) by dividing the case based on each situation as described above, in the energy management system 31, the priority order is determined. The control subject can be determined based on the above. As a result, the options of other devices that have not become the controlling entity are limited in their choices, and it is not necessary to perform complicated case classification, and the processing can be simplified.

  In addition, since the processing is distributed in each of the AC / DC conversion unit 41, the PV DC / DC conversion unit 42, and the battery DC / DC conversion unit 43, the load on the system control unit 47 can be reduced. Furthermore, it is possible to easily cope with a change in the priority order of a device that is a control entity that performs DC bus voltage control.

  Further, even when the devices connected to the DC bus 53 are expanded or contracted, it is possible to easily cope with the change by executing a process of determining a control subject that performs DC bus voltage control in each device. .

  For example, an energy management system 31 having a configuration example as shown in FIG. 13 will be described.

  FIG. 13 shows a configuration example in which an EV 37 and a DC load 39 are connected to the energy management system 31 shown in FIG.

  That is, in the energy management system 31 shown in FIG. 13, an AC / DC converter 41, a PV DC / DC converter 42, a battery DC / DC converter 43, and an EV DC / DC converter 44 are connected to the DC bus 53. And a load DC / DC conversion unit 45 are connected.

  At this time, as described above, the priority order of the control subject that performs DC bus voltage control is set such that the priority order becomes lower as the device that wants to use the power to the maximum extent effectively. For example, the power generated by the PV 35 is utilized to the maximum, power is preferentially supplied to the DC load 39, and power is preferentially supplied to the AC load 38 next to the DC load 39. Further, the surplus power is charged into the battery 36, and when the battery 36 is fully charged, the EV 37 is charged. When the load generated by the power generated by the PV 35 cannot cover the load, the power of the battery 36 is supplied. When the battery 36 is insufficient, the power is supplied from the EV 37.

  Thus, when it is desired to use power, the effective DC / DC conversion unit 42, the load DC / DC conversion unit 45, the AC / DC conversion unit 41, the battery DC / DC conversion unit 43, And the EV DC / DC conversion unit 44 in this order. Thus, the priority of the control subject that performs DC bus voltage control is as follows: EV DC / DC converter 44, battery DC / DC converter 43, AC / DC converter 41, load DC / DC converter 45, It is preferable that the order of the DC / DC converter 42 for PV is the order.

  The priority order information set in this order is stored in the memory of the system control unit 47. Then, when processing for determining a control subject that performs DC bus voltage control is started, an AC / DC converter 41, a PV DC / DC converter 42, a battery DC / DC converter 43, and an EV DC / DC conversion unit 44 and load DC / DC conversion unit 45 obtain priority information from system control unit 47 and individually execute the processing described with reference to the flowcharts of FIGS. To do.

  Note that the load DC / DC conversion unit 45 outputs power following the power consumption of the DC load 39, similarly to the AC / DC conversion unit 41, when it determines that it does not perform DC bus voltage control. Take control. In addition, when the EV DC / DC conversion unit 44 determines that it does not perform DC bus voltage control, the EV DC / DC conversion unit 44, like the AC / DC conversion unit 41, stops operation or charges / discharges according to a higher order instruction. Do.

  As described above, in the energy management system 31, even when the number of devices connected to the DC bus 53 increases, the number of devices increases by executing the process of determining the control entity that performs DC bus voltage control in each device. Can be easily accommodated.

  In the above-described embodiment, for example, the AC / DC converter 41, the PV DC / DC converter 42, and the battery DC / DC converter 43 communicate to perform DC bus voltage control. Control permission / inhibition information indicating that it is possible is transmitted from the higher priority device to the lower device. On the other hand, for example, is it possible to perform DC bus voltage control from a higher priority device to a lower priority device according to the level of the voltage input to the contact by connecting the devices to each other through electrical contacts? You may be notified about whether or not.

  For example, FIG. 14 shows a configuration example of a contact for notifying whether or not DC bus voltage control can be performed. In FIG. 14, the configuration of the AC / DC conversion unit 41 is described as an example, but the same configuration is applied to other devices.

  As shown in FIG. 14, the AC / DC conversion unit 41 includes a control circuit 61, an input terminal unit 62, a rectifying element 63, a rectifying element 64, and an output terminal unit 65.

  Each contact of the input terminal unit 62 is connected to an output terminal unit 65 of a higher priority device than the AC / DC conversion unit 41 (for example, the battery DC / DC conversion unit 43). The control circuit 61 is connected via a corresponding rectifying element 63. The control circuit 61 is connected to the output terminal unit 65 via the rectifying element 64, and each contact point of the output terminal unit 65 has a lower priority device than the AC / DC conversion unit 41 (for example, for PV). It is connected to the input terminal 62 of the DC / DC converter 42).

  In such a configuration, when the control circuit 61 cannot perform the DC bus voltage control, the control circuit 61 sets the potential of the signal output from the output terminal unit 65 to a low level (for example, 0 V) and performs the DC bus voltage control. If it can be performed, the potential of the signal output from the output terminal portion 65 is set to a high level (for example, 5 V).

  Therefore, when a device having a higher priority than the AC / DC conversion unit 41 can perform DC bus voltage control, a high-level signal is input to the input terminal unit 62 of the AC / DC conversion unit 41. . If any one of the signals input to the input terminal unit 62 is at a high level, the control circuit 61 of the AC / DC conversion unit 41 determines that the AC / DC conversion unit 41 does not perform DC bus voltage control. .

  Thus, based on the level of the signal input / output to / from the contact of the input terminal unit 62 and the output terminal unit 65, it is determined whether or not the higher-priority device performs DC bus voltage control between the devices. It can be carried out. Further, as shown in FIG. 13, even when devices connected to the DC bus 53 are added, it is easy to increase the number of devices by changing the connection of the respective input terminal portions 62 and output terminal portions 65. It can correspond to. Further, when the priority of the control subject that performs DC bus voltage control is changed, it can be dealt with by changing the connection.

  By the way, in general, for the operation of the DC / DC converter, a current continuous mode in which power is supplied to the load and a current smaller than a no load or a load that is about half the ripple current are output. There are two modes, the current discontinuous mode, which is a state of being present. Since the output voltage control method differs for each of these two modes, the DC / DC converter needs a predetermined switching time to switch the mode, so that it takes time to stabilize the control. Become.

  Therefore, the transition from the stop state to the operation state in which the DC / DC conversion unit supplies power to the load starts from the stop state and enters the current discontinuous mode, and then enters the current continuous mode. As described above, the DC / DC conversion unit needs to have a soft start function that requires a predetermined time from the stop state to the normal operation state in which power is supplied to the load.

  As described above, since the DC / DC conversion unit has the soft start function, the voltage of the DC bus becomes unstable depending on the state of each device connected to the DC bus. In addition, a predetermined time is required until the DC load obtains desired power. That is, when the DC load is activated and tries to suck current from the DC bus in a state where power is not supplied to the DC bus, the DC / DC converter increases the current from 0 A because it has a soft start function. It will take time. Nevertheless, if the DC load forcibly absorbs power, the DC / DC converter cannot supply power, and the voltage of the DC bus decreases.

  Therefore, in the energy management system 31, the system control unit 47 maintains the state where at least one device among the plurality of devices connected to the DC bus 53 always supplies power to the DC bus 53. Take control.

  For example, description will be given with reference to an energy management system 31 having a configuration example as shown in FIG.

  In the energy management system 31, control by the system control unit 47 is performed so that a state where power is always supplied to the DC bus 53 is maintained. That is, at least one of the AC / DC converter 41, the PV DC / DC converter 42, the battery DC / DC converter 43, and the EV DC / DC 44 connected to the DC bus 53 is a DC bus. 53, and at least one of the battery 36, the EV 37, the DC loads 39-1 and 39-2, and the AC / DC converter 41 is powered via the DC bus 53. Is maintained.

  Accordingly, at least one of the AC / DC conversion unit 41, the PV DC / DC conversion unit 42, the battery DC / DC conversion unit 43, and the EV DC / DC 44 connected to the DC bus 53 has a current It will operate in continuous mode. Therefore, for example, at least one of the AC / DC conversion unit 41, the PV DC / DC conversion unit 42, the battery DC / DC conversion unit 43, and the EV DC / DC 44 outputs even a little current. It is in a state. As a result, for example, the DC load 39-1 or 39-2 is activated and it is easy to cope with a sudden load fluctuation when the current is sucked from the DC bus, and the voltage of the DC bus 53 becomes unstable. It can be avoided.

  In addition, when power is always supplied to the DC bus 53, supplying power to a meaningless load is wasteful power consumption, so that it is not necessary to waste power. Priorities are set. For example, power supply to a DC load 39 (for example, a router or a telephone) that always requires power is set to the highest priority, charging to the battery 36 or EV 37 is set to the next priority, Reverse flow is the next priority. Then, power is supplied via the DC bus 53 in descending order of priority.

  Further, the system control unit 47 determines the presence or absence of power supply to the DC load 39-1 based on the output of the ammeter 52-2, and supplies the power to the DC load 39-2 based on the output of the ammeter 52-3. The presence or absence of power supply is determined. Further, the system control unit 47 directly communicates with the AC / DC conversion unit 41, the PV DC / DC conversion unit 42, the battery DC / DC conversion unit 43, and the EV DC / DC 44, thereby generating power. The presence / absence of power supply to the system 34, the PV 35, the battery 36, and the EV 37 is determined.

  With reference to the flowchart of FIG. 16, processing for maintaining a state where power is always supplied to the DC bus 53 will be described.

  In step S <b> 121, the system control unit 47 determines whether there is a device that supplies power to the DC bus 53. For example, the system control unit 47 communicates with the AC / DC conversion unit 41, the PV DC / DC 42, the battery DC / DC conversion unit 43, and the EV DC / DC 44 to confirm that power is not supplied. If it is confirmed, it is determined that there is no device supplying power to the DC bus 53. On the other hand, when the current is detected by the ammeter 52-2 or 52-3, the system control unit 47, or the AC / DC conversion unit 41, the PV DC / DC 42, the battery DC / DC conversion unit 43, and When it is confirmed that at least one of them communicates with the DC / DC 44 for EV and supplies power to the DC bus 53, it is determined that there is a device that supplies power to the DC bus 53.

  If the system control unit 47 determines in step S121 that there is no device supplying power to the DC bus 53, the process proceeds to step S122. In step S122, the system control unit 47 performs AC / DC conversion on the power supplied from the power system 34 to the AC / DC conversion unit 41 and outputs it to the DC bus 53, that is, the AC / DC conversion unit. 41 is controlled to operate in the direction of power purchase.

  After the process of step S122, or when it is determined in step S121 that there is a device that supplies power to the DC bus 53, the process proceeds to step S123.

  In step S123, the system control unit 47 determines whether power is being supplied from the DC bus 53 to the DC load 39-1 or 39-2. For example, when neither the ammeter 52-2 nor 52-3 detects the current, the system control unit 47 is not supplied with power from the DC bus 53 to the DC load 39-1 or 39-2. judge. On the other hand, when one of the ammeters 52-2 and 52-3 detects a current, the system control unit 47 is supplied with power from the DC bus 53 to the DC load 39-1 or 39-2. Is determined.

  If the system control unit 47 determines in step S123 that power is not being supplied from the DC bus 53 to the DC load 39-1 or 39-2, the process proceeds to step S124. That is, in this case, the DC loads 39-1 and 39-2 do not request power supply.

  In step S124, the system control unit 47 communicates with the battery DC / DC conversion unit 43 and the EV DC / DC 44, so that at least one SOC of the battery 36 and the EV 37 (battery thereof) can be charged. It is determined whether or not there is. If it is determined in step S124 that at least one of the SOCs of the battery 36 and the EV 37 is the remaining chargeable amount, the process proceeds to step S125, and the system control unit 47 determines whether or not the battery DC / DC conversion unit 43 Then, control is performed so that the battery 36 is charged or the EV DC / DC 44 is charged to the EV 37.

  On the other hand, when it is determined in step S124 that the SOC of the battery 36 is not the remaining chargeable amount and the SOC of the EV 37 is not the remaining chargeable amount, the process proceeds to step S126. That is, in this case, the SOCs of the battery 36 and the EV 37 are the remaining amount that can be discharged.

  In step S126, the system control unit 47 converts the power supplied via the DC bus 53 to the AC / DC conversion unit 41 by DC / AC conversion and reversely flows to the power system 34, that is, AC The DC / DC converter 41 is controlled to operate in the direction of power sale. In step S127, the system control unit 47 controls the battery DC / DC conversion unit 43 to discharge from the battery 36 or the EV DC / DC 44 to discharge from the EV 37. .

  If it is determined in step S123 that power is supplied from the DC bus 53 to the DC load 39-1 or 39-2, the process proceeds to step S128 after the process of step S125 or the process of step S127. . In step S128, the system control unit 47 controls the AC / DC conversion unit 41, the battery DC / DC conversion unit 43, and the EV DC / DC 44 to perform normal operation, and the processing is step. Returning to S121, the same processing is repeated thereafter.

  As described above, in the energy management system 31, it is possible to maintain a state in which power is constantly supplied to the DC bus 53, and it is possible to avoid the voltage of the DC bus 53 becoming unstable. The DC load 39 can quickly obtain desired power.

  Next, FIG. 17 is a block diagram showing a first modification of the energy management system. In addition, in the energy management system 31A shown in FIG. 17, the same code | symbol is attached | subjected about the block which is common in the energy management system 31 of FIG. 15, and the detailed description is abbreviate | omitted.

  That is, in the energy management system 31A, the two batteries 36-1 and 36-2 are connected to the power control device 32A, and the power control device 32A corresponds to the two battery DC / DC conversion units. 43-1 and 43-2. Further, the power control device 32A includes a DC / DC conversion unit 71 and an AC / DC conversion unit 72. One terminal of the DC / DC conversion unit 71 is connected to the DC bus 53, and the other terminal of the DC / DC conversion unit 71 and the DC side terminal of the AC / DC conversion unit 72 are both connected to the system control unit. 47. The AC side terminal of the AC / DC conversion unit 72 is connected to the power line 40 that connects the AC / DC conversion unit 41 and the power system 34.

  In the energy management system 31 </ b> A, any one or more of the batteries 36-1 and 36-2, the EV 37, the DC load 39, and the AC / DC conversion unit 41 must be powered via the DC bus 53. Is supplied, and at least one of the batteries 36-1 and 36-2, PV 35, EV 37, and AC / DC converter 41 always outputs power to the DC bus 53. The state continues.

  For example, when there is a discharge from the battery 36-1 or 36-2 and the discharge from the AC / DC converter 41 is larger than the power consumption of the AC load 38, the PV 35 to the PV DC / DC converter 42. The power output to the DC bus 53 is supplied to the DC load 39 via the. On the other hand, in other cases, electric power is supplied between the batteries 36-1 and 36-2 and the EV 37.

  That is, in the energy management system 31 </ b> A, by having the two batteries 36-1 and 36-2, charging and discharging can be performed between the batteries 36-1 and 36-2, and power is supplied to the DC bus 53. It is possible to maintain the state of constantly supplying. At this time, in order to suppress waste of power, the power to be charged / discharged between the batteries 36-1 and 36-2 is minimized, and the battery 36-1 is used when there is no other device that requires power. And 36-2 are charged and discharged. The batteries 36-1 and 36-2 are controlled so as not to be fully charged at the same time, and when one of them is fully charged, the battery 36-1 and 36-2 are discharged from one of them and charged to the other.

  Further, for example, when the EV 37 is in use and not connected to the DC bus 53, when the AC load 38 and the DC load 39 do not consume power, or when the PV 35 does not generate power at night, the batteries 36-1 and 36- Even when the second power is not allowed to flow backward to the power system 34, the state in which power is always supplied to the DC bus 53 can be maintained by having the two batteries 36-1 and 36-2. it can.

  Thus, by maintaining the state where power is always supplied to the DC bus 53, the voltage of the DC bus 53 can be stabilized. Then, by setting a state in which even a little current is being output from the battery DC / DC conversion unit 43-1 or 43-2 to the DC bus 53, the DC load 39 suddenly starts to request power. It can cope with fluctuations in power.

  Further, in the energy management system 31 </ b> A, the DC / DC conversion unit 71 and the AC / DC conversion unit 72 are provided, so that the system control unit 47 can acquire power from both the DC bus 53 and the power line 40. At this time, the voltage output from the AC / DC conversion unit 72 to the system control unit 47 side is slightly higher than the voltage output from the DC / DC conversion unit 71 to the system control unit 47. To. As a result, during normal times, power is supplied from the power system 34 to the system control unit 47, and during blackouts, power is supplied from the DC bus 53 to the system control unit 47.

  And in the energy management system 31A, since it is set as the state which always supplies electric power with respect to the DC bus 53, when a power failure generate | occur | produces, it can supply electric power to the system control part 47 rapidly.

  That is, when the power is not always supplied to the DC bus 53, when a power failure occurs, the battery DC / DC conversion unit 43-1 or 43-2 is activated and the DC bus 53 is activated. After the output of power is started and the DC / DC conversion unit 71 is activated, power is supplied to the system control unit 47. As described above, conventionally, two steps are required until power is supplied to the system control unit 47, and quick power supply cannot be performed. In the energy management system 31A, power is supplied to the system control unit 47 quickly. be able to.

  In the energy management system 31A, it is preferable to use, as the DC load 39, for example, a device that requires 24 hours of power supply such as a router, a telephone, an emergency lighting, and a power supply for a fire alarm. is there. Thereby, even if the state where power is always supplied to the DC bus 53 is maintained, wasteful consumption of power can be avoided. Further, when a device that always requires such power is exchanged for maintenance or the like, power is supplied to the DC bus 53 by performing mutual power between the batteries 36-1 and 36-2 and the EV 37. It is possible to maintain the state of constantly supplying.

  As described above, in the energy management system 31 </ b> A, it is possible to prevent the voltage of the DC bus 53 from becoming unstable by maintaining a state in which power is constantly supplied to the DC bus 53. The DC load 39 can quickly obtain desired power.

  Next, FIG. 18 is a block diagram showing a second modification of the energy management system. In addition, in the energy management system 31B shown in FIG. 18, the same code | symbol is attached | subjected about the block which is common in the energy management system 31A of FIG. 17, and the detailed description is abbreviate | omitted.

  That is, the energy management system 31B includes a dedicated DC load 81 and a DC / DC conversion unit 73 in place of the battery 36-2 and the battery DC / DC conversion unit 43-2 in FIG. It is configured differently.

  In the energy management system 31B, at least one of the battery 36-1, the dedicated DC load 81, the EV 37, the DC load 39, and the AC / DC conversion unit 41 is always connected via the DC bus 53. The state in which power is supplied and any one or more of the batteries 36-1, PV35, EV37, and AC / DC converter 41 is always outputting power to the DC bus 53 continues. Is done.

  In the energy management system 31B, for example, when the PV 35, EV 37, AC load 38, and DC load 39 are not exchanged, if the battery 36 is not fully charged, the battery 36 is charged from the AC / DC converter 41. Is called. In this case, if the battery 36 is fully charged, power is supplied from the battery 36 to the dedicated DC load 81.

  With such a configuration, the energy management system 31B can maintain a state in which power is constantly supplied to the DC bus 53, and can prevent the voltage of the DC bus 53 from becoming unstable. . The DC load 39 can quickly obtain desired power.

  The series of processes described above can be executed by hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software executes various functions by installing a computer incorporated in dedicated hardware or various programs. For example, the program is installed in a general-purpose computer from a program recording medium.

  In a computer, programs stored in ROM (Read Only Memory) or programs stored in a storage unit such as a hard disk or non-volatile memory are loaded into RAM (Random Access Memory) and CPU (Central Executed by the Processing Unit). Thereby, the series of processes described above are performed.

  These programs are stored in advance in a storage unit, or via a communication unit such as a network interface, or a magnetic disk (including a flexible disk), an optical disk (CD-ROM (Compact Disc-Read Only). Memory, DVD (Digital Versatile Disc, etc.), magneto-optical disk, or drive that drives removable media such as semiconductor memory can be installed in the computer.

  The program executed by the computer may be a program that is processed in time series in the order described in this specification, or in parallel or at a necessary timing such as when a call is made. It may be a program for processing. Further, the program may be processed by a single CPU, or may be processed in a distributed manner by a plurality of CPUs. In the present specification, the term “system” represents the entire apparatus constituted by a plurality of apparatuses.

  Note that the present embodiment is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present disclosure.

  31 energy management system, 32 power control device, 33 ammeter, 34 power system, 35 PV, 36 battery, 37 EV, 38 AC load, 39 DC load, 40 power line, 41 AC / DC converter, 42 DC / DC for PV DC converter, 43 DC / DC converter for battery, DC / DC converter for 44 EV, 45 DC / DC converter for load, 46 Distribution board, 47 System controller, 51 Breaker, 52 Ammeter, 53 DC bus

Claims (14)

A direct current bus serving as a route for supplying direct current power;
A plurality of power supply devices connected to the DC bus, for performing at least one of output of DC power to the DC bus and input of DC power from the DC bus, and
For each of the plurality of power supply devices, the power supply device that is the control entity is determined based on the priority of the power supply device that is the control entity that controls the voltage of the DC bus to be constant. . The plurality of power supply devices are:
Based on controllability information that indicates whether or not each of the power supply devices, which is higher in priority than itself, can be controlled so that the voltage of the DC bus is constant, Determine whether to become the control subject,
The power control apparatus according to claim 1, wherein the control availability information is supplied to another power supply device having a lower priority than each other. The power control apparatus according to claim 1, wherein among the plurality of power supply devices, the priority order is set lower for the power supply device for which power is to be used effectively. The plurality of power supply devices acquire the priority order information from a storage unit that stores the priority order information in which the priority order is set, and determine whether or not each of the power supply devices becomes the control subject. The power control apparatus described. The plurality of power supply devices are:
The priority order is connected to each other by the electrical contact with the other power supply equipment higher than each one, and the priority order is connected to each other the lower power supply equipment from each one by an electrical contact,
When it is determined that the other priority power supply device is the controlling entity, a signal of a predetermined level is supplied to an electrical contact with the other power supply device having a higher priority. And
The power control apparatus according to claim 1, wherein when it is determined that the control apparatus itself is the control entity, a signal of a predetermined level is supplied to an electrical contact with the other power supply device having a lower priority. The power control apparatus according to claim 1, wherein at least one of the plurality of power supply devices always supplies power to the DC bus. As the plurality of power supply devices,
A first power supply device for stepping up / down a voltage of DC power from a power generation unit that generates power using natural energy and supplying power to the DC bus;
A second power supply device for stepping up and down the voltage of the DC power from the power storage unit that stores the power to supply power to the DC bus;
The power control apparatus according to claim 6, wherein at least a third power supply device that converts AC power from a power system that supplies AC power into DC power and supplies power to the DC bus is used. The power control apparatus according to claim 6, wherein power is always supplied to the DC bus by connecting a DC load that constantly consumes power supplied via the DC bus to the DC bus. The power control apparatus according to claim 6, wherein power is always supplied to the DC bus by causing the power supplied via the DC bus to flow backward to the power system. A plurality of power use units that use power supplied via the DC bus are connected to the DC bus, and the DC buses are used in descending order of priority of using the power among the plurality of power use units. The power control apparatus according to claim 6, wherein electric power is supplied via a power source. A plurality of power storage units that store power are connected to the DC bus via the plurality of power supply devices that step up and down the voltage of the DC power from the corresponding power storage units to supply power to the DC bus. The power control apparatus according to claim 6, wherein power is always supplied to the DC bus by charging and discharging between the power storage units. A direct current bus serving as a route for supplying direct current power;
A power control method for a power control apparatus, comprising: a plurality of power supply devices connected to the DC bus, and performing at least one of output of DC power to the DC bus and input of DC power from the DC bus. ,
A step of determining, for each of the plurality of power supply devices, the power supply device that is the control entity based on the priority of the power supply device that is the control entity that controls the voltage of the DC bus to be constant. Power control method. A direct current bus serving as a route for supplying direct current power;
A computer that controls a power control apparatus that is connected to the DC bus and includes a plurality of power supply devices that perform at least one of output of DC power to the DC bus and input of DC power from the DC bus. A program,
A step of determining, for each of the plurality of power supply devices, the power supply device that is the control entity based on the priority of the power supply device that is the control entity that controls the voltage of the DC bus to be constant. A program that causes a computer to execute processing. A solar power generation unit that generates power according to the amount of light received by the sunlight;
A power storage unit for storing electric power;
A direct current bus serving as a route for supplying direct current power;
A first power supply device connected to the DC bus and outputting the power generated by the photovoltaic power generation unit to the DC bus;
A second power supply device connected to the DC bus, outputting power of the power storage unit to the DC bus, and storing at least one of power input from the DC bus to the power storage unit;
At least one of converting AC power from a power system connected to the DC bus and supplying AC power to DC power and outputting to the DC bus, and converting DC power input from the DC bus to AC power A third power supply device for performing
For each of the first to third power supply devices, the power supply device to be the control entity is determined based on the priority of the power supply device to be a control entity that controls the DC bus voltage to be constant. Energy management system.

Images