JP2015149861A - Energy management apparatus, and energy management method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy management apparatus and an energy management method, capable of improving the power efficiency of an overall system including charging to a storage battery.SOLUTION: A power control unit 81b of an energy management apparatus 81 supplies generated power by a fuel cell 63 to a specific load 80 when a power generated by a solar cell 64 is lower than a load power at blackout. Then, the power control unit 81b, if the power generated by the fuel cell 63 is lower than the load power, compensates a difference between the load power and the power generated by the fuel cell 63 with the power generated by the solar cell 64. Further, the power control unit 81b charges a storage battery 62 using a surplus power not consumed in the specific load 80 among the power generated by the solar cell 64.

Description

  The present invention generally relates to an energy management device and an energy management method, and more particularly to an energy management device and an energy management method for managing a combination of a solar cell, a storage battery, and a cogeneration device.

  2. Description of the Related Art Conventionally, there is a power generation system that supplies electric power inside a consumer using a cogeneration device such as a solar cell or a fuel cell, or a storage battery. In this type of system, power is supplied to the load by combining the generated power of the solar battery, the generated power of the cogeneration apparatus, and the discharged power of the storage battery. For example, if the generated power of the solar cell is lower than the load power, the generated power of the solar cell and the generated power of the fuel cell are used together to supply power to the load, and the surplus of the generated power of the fuel cell is charged to the storage battery. (See, for example, Patent Document 1).

  The cogeneration device generates hot water using exhaust heat generated during power generation, and stores the generated hot water in a hot water storage tank. The user can use the hot water in the hot water storage tank.

JP 2010-259303 A

  In a conventional power generation system, there is a system that cannot charge a storage battery with power generated by a cogeneration device such as a fuel cell. In addition, the solar battery cannot generate power at night or the like, and cannot charge the storage battery.

  In such a power generation system, it is required to improve the power efficiency of the entire system including charging of the storage battery using each generated power of the solar battery and the cogeneration apparatus.

  This invention is made | formed in view of the said reason, The objective can improve the power efficiency of the whole system including the charge to a storage battery using each power generation of a solar cell and a cogeneration apparatus. To provide an energy management apparatus and an energy management method.

  The energy management device of the present invention includes a power control unit that controls power supply to a load using a solar cell, a storage battery, and a cogeneration device, and the power control unit is configured so that the generated power of the solar cell is If the power consumption of the load is less than or equal to the load, the generated power of the cogeneration device is supplied to the load, and if the generated power of the cogeneration device is less than the power consumption of the load, the power consumption of the load and the cogeneration The difference from the generated power of the device is supplemented with the generated power of the solar battery, and the storage battery is charged using surplus power that is not consumed by the load among the generated power of the solar battery.

  In this invention, when the generated power of the solar cell exceeds the power consumption of the load, the power control unit supplies only the generated power of the solar cell to the load, and out of the generated power of the solar cell. It is preferable to charge the storage battery using surplus power that is not consumed by the load.

  In the present invention, the power control unit is configured such that, when the generated power of the solar battery is less than or equal to the power consumption of the load, the generated power of the solar battery out of the power consumption of the load when the storage battery is fully charged. It is preferable to decrease the ratio of the generated power of the cogeneration apparatus in the power consumption of the load.

  In the present invention, the cogeneration apparatus preferably generates hot water during power generation, and stops power generation when the amount of heat stored in a hot water storage tank for storing the generated hot water becomes a predetermined amount or more.

  In this invention, it is preferable to provide a notification signal output unit that outputs a notification signal requesting that the hot water in the hot water storage tank be used when the amount of heat stored in the hot water storage tank exceeds a threshold value.

  In the present invention, the power control unit converts the generated power of the solar battery and the generated power of the storage battery into AC power and supplies the load to the load so that the output of the power converter is less than the upper limit value. It is preferable to control the power generation of the cogeneration apparatus.

  In this invention, when the power consumption of the load is equal to or higher than the upper limit value of the output of the power converter, the power control unit calculates a difference obtained by subtracting the generated power of the cogeneration device from the power consumption of the load. If the output of the power conversion device is less than the upper limit value, it is preferable to start the power generation of the cogeneration device.

  The energy management method of the present invention is a power management method for controlling power supply to a load using a solar cell, a storage battery, and a cogeneration device, and the generated power of the solar cell is equal to or less than the power consumption of the load. If the generated power of the cogeneration device is supplied to the load, and the generated power of the cogeneration device is less than the power consumption of the load, the power consumption of the load and the generated power of the cogeneration device This difference is supplemented with the generated power of the solar battery, and the storage battery is charged using surplus power that is not consumed by the load among the generated power of the solar battery.

  As described above, when the generated power of the solar battery is less than or equal to the power consumption of the load, the cogeneration system will cover the power consumption of the load as much as possible, and the surplus power of the solar battery will be charged to the storage battery, so that the system as a whole Can be used efficiently. Further, when the solar cell cannot generate power, such as at night, the power consumption of the load can be covered by the cogeneration device.

  Therefore, the energy management device and the energy management method of the present invention have an effect that the power efficiency of the entire system including charging of the storage battery can be improved by using the generated power of the solar cell and the cogeneration device.

It is a block diagram which shows the outline of the energy management system using the energy management apparatus of embodiment. It is a block diagram which shows the whole structure of an energy management system same as the above. It is a table figure which shows an example of the information table which the measuring apparatus same as the above produced | generated. It is a table figure which shows an example of the information table which the energy management apparatus same as the above produced | generated. It is a block diagram which shows an example of the electric power feeding path of the alternating current power in the energization period same as the above. It is a block diagram which shows an example of the electric power feeding path of alternating current power during a power failure period same as the above. It is a flowchart which shows the electric power control at the time of a power failure same as the above.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment)
The overall configuration of the energy management system (power management system) is shown in FIG. The energy management system includes a distribution board 10, a self-supporting distribution board 20, a power switch 30, a measuring device 40, a power conversion device 50, a storage battery 62, a fuel cell 63, an energy management device 81, and a display terminal 82 as main components. .

  Further, FIG. 1 is a block diagram showing an outline of the configuration of the energy management system, and a part of the configuration of FIG. 2 is omitted. In FIG. 1, a broken line indicates an AC circuit, a one-dot chain line indicates a DC circuit, and a solid line indicates an information transmission path.

  First, the power supply system includes four types of power sources 61, a storage battery 62, a fuel cell 63, and a solar cell 64 as power sources for supplying power to a load.

  The system power source 61 is a commercial power source that a commercial power supply company such as an electric power company supplies commercial power through the distribution network.

  The storage battery 62 is composed of a lithium ion battery or the like.

  The fuel cell 63 is a cogeneration apparatus that uses hydrogen gas generated by reforming fuel gas containing methane or propane, and a hot water storage tank 632 is attached to the power generation unit 631. The power generation unit 631 generates power using the fuel cell unit, and further generates hot water using exhaust heat generated during the power generation operation. The hot water storage tank 632 stores hot water generated during the power generation operation of the power generation unit 631. Furthermore, when the amount of heat stored in the hot water storage tank 632 instead of hot water is insufficient, the power generation unit 631 heats the hot water in the hot water storage tank 632 using exhaust heat generated during the power generation operation. That is, “generate hot water using exhaust heat generated during power generation operation” means “increase the amount of hot water in hot water storage tank 632 using exhaust heat generated during power generation operation”, “exhaust heat generated during power generation operation” This includes both concepts of “heating the hot water in the hot water storage tank 632 by using“.

  As described above, the fuel cell 63 has both functions of power generation and water heating. The fuel cell 63 stops the power generation by the power generation unit 631 when the hot water storage amount of the hot water storage tank 632 becomes full. Here, the state where the hot water storage amount of the hot water storage tank 632 is full is assumed to be the full storage state where the heat storage amount of the hot water storage tank 632 reaches the upper limit (first predetermined amount).

  In addition, the fuel cell 63 can communicate with a remote controller 63 a used for managing the operating state of the fuel cell 63.

  The solar cell 64 performs power generation using sunlight.

  In the present embodiment, the solar cell 64 is illustrated as a power source capable of reverse power flow to the system power source 61. However, the solar cell 64 is a power source that generates power using natural energy such as wind power, hydropower, and geothermal heat. Can be substituted. In the present embodiment, the storage battery 62 and the fuel cell 63 are illustrated as power supplies that do not perform reverse power flow to the system power supply 61. Further, instead of the fuel cell 63, it is also possible to use a cogeneration device that generates power using a gas engine (gas micro turbine).

  The distribution line L1 connected to the system power supply 61 is connected to the distribution board 10.

  The distribution board 10 incorporates a main breaker 11 whose primary side is connected to the distribution line L1 and a plurality of branch breakers 12 that branch power on the secondary side of the main breaker 11 in a housing (not shown). doing. Each branch breaker 12 supplies power to the load 70 through the branch line L2. In FIG. 2, a plurality of loads 70 are collectively denoted by reference numerals, but the reference numerals 70 indicate individual loads.

  Furthermore, the distribution board 10 incorporates an interconnection breaker 13 and a current sensor X3. The interconnection breaker 13 is connected to the primary circuit (distribution line L1) of the main breaker 11, and is inserted between the power converter 50 and the distribution line L1. The interconnection breaker 13 forms a path for supplying the power generated by the solar battery 64 to the primary circuit of the main breaker 11 and forms a path for using the power received from the system power supply 61 for charging the storage battery 62. . The interconnection breaker 13 is a so-called remote control breaker, and is switched on / off according to an instruction from the power conversion device 50.

  The current sensor X3 is arranged to detect a current passing through the main breaker 11. In the illustrated example, the current sensor X3 is arranged in the distribution line L1 so as to measure the current passing through the electrical path between the connection point with the interconnection breaker 13 and the main breaker 11. The current sensor X3 is arranged so as to individually detect currents of two voltage lines (U phase and W phase) of the single phase three wires.

  The current sensor X3 assumes a current transformer including a core as a specific configuration, but may be configured to use a coreless coil (so-called Rogowski coil) or a magnetic sensor. The same applies to the current sensors X1, X2, and X4 to X7 described below, and the specific configuration of each of the current sensors X1, X2, and X4 to X7 conforms to the configuration of the current sensor X3.

  One of the branch breakers 12 built in the distribution board 10 is connected to the self-standing distribution board 20 through a branch line L3 corresponding to a single-phase three-wire. On the branch line L3, there is a power switch 30 that selects one of the power supplied from the branch breaker 12 of the distribution board 10 and the power supplied from the power converter 50 and supplies it to the independent distribution board 20. Has been inserted. The power switch 30 includes an electromagnetic relay that conducts / cuts off the electric power supplied from the branch breaker 12 and the electric power supplied from the power converter 50.

  The independent distribution board 20 forms a path for supplying power to the load 80, the measurement device 40, the measurement point switching device 90, which will be described later, and the like that need to be fed even during a power failure period when no power is supplied from the system power supply 61. In FIG. 2, a plurality of loads 80 are collectively indicated by a reference numeral 80, but the reference numeral 80 indicates an individual load. Of the loads 80, the load 81 is an energy management device, and the load 82 is a display terminal, which will be referred to as the energy management device 81 and the display terminal 82 hereinafter.

  In order to distinguish between the load 70 and the load 80, the load 70 is referred to as a “general load”, and the load 80 is referred to as a “specific load”. The specific load 80 includes an energy management device 81 and a display terminal 82.

  The self-supporting distribution board 20 incorporates a main breaker 21 and a plurality of branch breakers 22 that branch power on the secondary side of the main breaker 21 in a housing (not shown). The primary side of the main breaker 21 is connected to the power switch 30 and is supplied with either the power supplied from the branch breaker 12 of the distribution board 10 or the power supplied from the power converter 50. Is done. Each branch breaker 22 supplies power to the specific load 80, the measurement device 40, and the measurement point switching device 90 through the branch line L4.

  The specific load 80, the measurement device 40, and the measurement point switching device 90 can be operated by the power supplied from the distribution board 10 during the energization period in which the power is supplied from the system power supply 61. In addition, the specific load 80, the measurement device 40, and the measurement point switching device 90 can be operated by the power supplied from the power conversion device 50 during a power failure period in which power is not supplied from the system power supply 61.

  One of the branch breakers 22 is connected to the fuel cell 63 through the connection line L5. The power generated by the fuel cell 63 can be supplied to the specific load 80, the measuring device 40, and the measuring point switching device 90 via the connection line L5 and the independent distribution board 20. Moreover, since the electric power generated by the fuel cell 63 can be supplied to the distribution board 10 through the main breaker 21, the electric power can also be supplied from the fuel cell 63 to the general load 70.

  The power converter 50 includes a storage battery 62 and a solar battery 64 connected to each other, and has a function of transferring power to and from the distribution board 10 and a function of supplying power to the independent distribution board 20. 51 is provided. Furthermore, the power conversion device 50 includes a transformer 52 that converts the power output from the power converter 51 by two lines into three lines.

  The power converter 51 converts the DC power generated by the solar battery 64 into AC power that can be linked to the system power supply 61. Further, the power converter 51 monitors and controls the charging current and discharging current of the storage battery 62, and converts the DC power discharged by the storage battery 62 into AC power.

  Furthermore, the power converter 51 includes an interconnection terminal 55 connected to the interconnection breaker 13 and an independent output unit 56 that supplies electric power to the transformer 52. Then, the power converter 51 determines the energization period / power failure period of the system power supply 61 (whether or not power can be received from the system power supply 61) using the voltage between the terminals of the interconnection terminal 55.

  The interconnection terminal 55 is connected to the distribution line L <b> 1 via the interconnection breaker 13, and system interconnection is possible during the energization period of the system power supply 61. Specifically, the interconnection terminal 55 is a single-phase three-wire system, is connected to the interconnection breaker 13 through the connection line L6, and the interconnection breaker 13 is connected to the distribution line L1 that is the primary side of the main breaker 11. Connected through.

  The connection line L6 is a path for supplying AC power obtained from the generated power of the solar battery 64 or the stored power of the storage battery 62 to the main breaker 11 of the distribution board 10, or the generated power of the solar battery 64 is reversed to the distribution line L1. Used as a tidal path. Further, the connection line L6 is also used as a path for charging the storage battery 62 using electric power supplied from the system power supply 61 through the distribution line L1. The output voltage between the terminals of the interconnection terminal 55 is determined by the line voltage of the system power supply 61.

  Of the power generated by the solar battery 64, surplus power that is not used by the consumer flows backward to the distribution line L1, and the power converter 51 also has a function of monitoring and controlling the power flowing backward. The output of the current sensor X2 is input to the power converter 51. The power converter 51 determines whether or not a reverse power flow from the consumer to the system power supply 61 is generated based on the output of the current sensor X2, and the power flow is reversed. Judge power. Current sensor X2 is arranged to individually detect currents passing through two voltage lines in a single-phase three-wire.

  The power converter 51 uses the relationship between the phase of the current monitored by the current sensor X2 and the phase of the voltage between the terminals of the interconnection terminal 55 to determine whether a reverse power flow from the customer to the system power supply 61 has occurred. Judging. The voltage between the terminals in the interconnection terminal 55 has the same voltage and the same phase as the line voltage of the distribution line L1 electrically connected to the interconnection terminal 55. Therefore, the power converter 51 uses the voltage waveform between the terminals of the interconnection terminal 55 and the current waveform monitored by the current sensor X2, and reverses the sign of an integrated value obtained by integrating the power for one period of the voltage waveform. Determine whether there is a tidal current.

  In addition, the storage battery 62 does not perform reverse power flow to the system power supply 61. Therefore, the power converter 51 uses the output of the current sensor X2 in the same manner as described above in order to monitor whether or not the stored power of the storage battery 62 is flowing backward without being consumed by the consumer.

  On the other hand, the self-supporting output unit 56 of the power converter 51 does not output power to the transformer 52 during the energization period of the system power supply 61 and outputs power to the transformer 52 during the power failure period of the system power supply 61. The self-supporting output unit 56 is a single-phase two-wire system, and is connected to the primary side of the transformer 52 by two wires, and only supplies power to the transformer 52. The voltage between the terminals of the self-supporting output unit 56 is kept at a constant voltage (for example, 200V). A self-supporting terminal 57 is provided on the secondary side of the transformer 52, and the power output from the self-supporting terminal 57 is derived from at least one of the solar battery 64 and the storage battery 62. The self-supporting terminal 57 is connected to the power switch 30 through a connection line L7 corresponding to a single-phase three-wire. In the power conversion device 50, the maximum power (constraint output) that can be output from the self-supporting terminal 57 is determined in advance. When the output of the self-supporting terminal 57 exceeds the constraint output, the power converter 51 stops the output from the self-supporting output unit 56 and stops the output from the self-supporting terminal 57.

  The power converter 51 determines the energization period / power failure period of the system power supply 61 using the voltage between the terminals of the interconnection terminal 55. Then, the power converter 51 controls the switching operation of the power switch 30 using the determination result of the energization period / power failure period. The power switch 30 connects the connection line L3 to the main breaker 21 of the independent distribution board 20 and connects the connection line L7 to the main breaker 21 of the independent distribution board 20 according to an instruction from the power converter 51. Switch between states. That is, the independent distribution board 20 is supplied with power through the distribution board 10 during the energization period in which power is supplied from the system power supply 61, and is distributed from the power conversion device 50 during a power outage period when the power from the system power supply 61 stops. Electric power is supplied without passing through the board 10. In addition, although the switching operation of the power switch 30 is performed by the contact signal which the power converter 51 outputs, for example, the signal form is not limited.

  In addition, the power converter 51 transmits the determination result (power failure information) of the energization period / power failure period to the measuring device 40. Further, the power converter 51 transmits information on the storage battery 62 (accumulated power, discharge power, device information, error information, etc.) and information on the solar cell 64 (generated power, device information, error information, etc.) to the measuring device 40. To do.

  Note that the communication path between the power converter 51 and the measuring device 40, the communication path between the power converter 51 and the storage battery 62, and the communication path between the power converter 51 and the solar battery 64 have specifications according to the RS485 standard, for example. Perform serial communication. It is not essential that the communication path conforms to the RS485 standard, and the communication path can also be realized by wireless communication or power line carrier communication using a wired communication path. Moreover, you may use combining these communication technologies.

  Furthermore, the power conversion device 50 includes a switching instruction unit 53 that gives an instruction by a switching signal to the measurement point switching device 90. The switching instruction unit 53 gives a switching signal indicating the energization period / power failure period to the measurement point switching device 90, and this switching signal is also transmitted to the fuel cell 63 through the measurement point switching device 90. In addition, this switching signal is a contact signal, for example, and the signal form is not limited.

  The measuring point switching device 90 has a current value monitored by the fuel cell 63 as a current sensor X3 built in the distribution board 10 and a current sensor X5 that measures a current passing through the main breaker 21 of the independent distribution board 20. Select from which to get. That is, the measuring point switching device 90 connects the current sensor X3 to the fuel cell 63 during the energization period of the system power supply 61, and connects the current sensor X5 to the fuel cell 63 during the power failure period of the system power supply 61.

  Since the fuel cell 63 does not perform reverse power flow in this embodiment, the fuel cell 63 determines whether or not reverse power flow has occurred based on the current monitored by the current sensors X3 and X5. That is, the fuel cell 63 uses each output of the current sensors X3 and X5 in order to monitor whether or not the generated power of the fuel cell 63 is flowing backward without being consumed by the consumer. Specifically, the fuel cell 63 uses the output of the current sensor X3 in order to detect a reverse power flow to the system power supply 61 when the system power supply 61 is energized. Further, the fuel cell 63 uses the output of the current sensor X5 in order to detect a reverse power flow to the connection line L7 at the time of a power failure of the system power supply 61.

  That is, the outputs of the current sensors X3 and X5 are input to the fuel cell 63 via the measurement point switching device 90, and the fuel cell 63 is output from the fuel cell 63 based on the outputs of the current sensors X3 and X5. In addition, it is determined whether or not all electric power is consumed by consumers.

  Further, the electric power generated by the fuel cell 63 is monitored by the current sensor X4. The current sensor X4 monitors the current passing through the connection line L5 that connects the fuel cell 63 and the branch breaker 22. The output of the current sensor X4 is input to the measuring device 40, and the measuring device 40 monitors the power passing through the connection line L5.

  The fuel cell 63 communicates with the power conversion device 50 through the measurement point switching device 90. That is, the switching signal indicating the energization period / power failure period of the system power supply 61 is also notified from the power conversion device 50 to the fuel cell 63 through the measurement point switching device 90. Therefore, the fuel cell 63 can recognize which power is supplied from the interconnection terminal 55 or the self-supporting terminal 57 of the power conversion device 50.

  Further, the power conversion device 50 communicates with the remote controller 54 in order to allow the user to instruct and monitor the operation.

  A current sensor X <b> 1 is arranged on the primary distribution line L <b> 1 of the main breaker 11 in the consumer in order to measure the power received from the system power supply 61.

  In the distribution line L1, a current sensor X2 is disposed between the current sensor X1 and the main breaker 11 in order to detect a reverse power flow to the system power supply 61. The current sensor X2 monitors the current at a position closer to the system power supply 61 than the connection point between the main breaker 11 and the interconnection breaker 13 in the distribution line L1.

Further, in the distribution line L1, a current sensor X3 is arranged so as to measure a current passing through the electric path between the connection point with the interconnection breaker 13 and the main breaker 11. The current sensor X4 monitors the current passing through the connection line L5 connecting the fuel cell 63 and the branch breaker 22, and the current sensor X5 measures the current passing through the main breaker 21 of the self-supporting distribution board 20. The current sensor X6 is disposed on the branch line L2 and monitors the current supplied to the general load 70. The current sensor X7 is disposed on the branch line L4 and monitors the current supplied to the specific load 80.

  And current sensor X1, X4, X6, X7 is connected to measuring device 40, and measuring device 40 acquires each current value which current sensors X1, X4, X6, and X7 measured regularly.

  The measuring device 40 measures the power received from the system power supply 61 based on the current value measured by the current sensor X1, and generates power purchase information (power purchase information, power sale information). The measuring device 40 measures the generated power of the fuel cell 63 based on the current value measured by the current sensor X4, and generates power generation information (fuel cell). Moreover, the measuring device 40 measures the power consumption of the general load 70 based on the current value measured by the current sensor X6, and generates power consumption information (general load). The measuring device 40 measures the power consumption of the specific load 80 based on the current value measured by the current sensor X7, and generates power consumption information (specific load).

  Furthermore, the measurement device 40 communicates with the power conversion device 50 to thereby obtain information on the storage battery 62 (accumulated power, discharge power, device information, error information, etc.) and information on the solar cell 64 (generated power, device information, error information). Etc.), the power failure information indicating the judgment result of the energization period / power failure period is acquired.

  The measuring device 40 stores the above information in the information table 401. FIG. 3 is an example of the information table 401 generated by the measurement device 40.

  Then, the measuring device 40 uses the information on power trading, power consumption information (general load), power consumption information (specific load), storage battery 62 information, solar battery 64 information, power outage information, power generation information (fuel cell) as energy. Wireless transmission to the management device 81.

  The energy management device 81 includes an information acquisition unit 81a, a power control unit 81b, a display data generation unit 81c, and a device control unit 81d (see FIG. 1).

  The energy management device 81 is configured to be capable of wireless communication with the measurement device 40. And the information acquisition part 81a is information on buying and selling power, power consumption information (general load), power consumption information (specific load), information on the storage battery 62, information on the solar battery 64, power failure information, and power generation information (fuel cell). Obtained from the measuring device 40. Furthermore, the energy management device 81 is configured to be able to wirelessly communicate with the fuel cell 63, and the information acquisition unit 81a includes information on the fuel cell 63 (the amount and temperature of hot water stored in the hot water storage tank 632, device information, error information, etc.). Also get. The energy management device 81 stores the above information in the information table 811. FIG. 4 is an example of the information table 811 generated by the energy management device 81. Furthermore, the energy management device 81 can communicate with the power converter 51 via the measurement device 40 by wirelessly communicating with the measurement device 40.

  Then, the power control unit 81b controls the power converter 51 and the fuel cell 63 based on the above information, and controls each power supply by the storage battery 62, the fuel cell 63, and the solar cell 64.

  For example, the power control unit 81b supplies power to the general load 70 and the specific load 80 using the power of the system power supply 61, the storage battery 62, the fuel cell 63, and the solar battery 64 during the energization period of the system power supply 61. Do. Moreover, the electric power control part 81b will charge the storage battery 62 using each electric power of the system power supply 61 and the solar cell 64 if it is an electricity supply period. In addition, the power control unit 81b also controls the amount of power to be reversely flowed to the system power supply 61 using the generated power of the solar battery 64 during the energization period. FIG. 5 shows an example of an AC power supply path during the energization period of the system power supply 61.

  Further, the power control unit 81 b supplies power to the specific load 80 using each power of the storage battery 62, the fuel cell 63, and the solar cell 64 during the power failure period of the system power supply 61. Moreover, the electric power control part 81b will charge the storage battery 62 using the electric power of the solar cell 64 if it is a power failure period. FIG. 6 shows an example of a feeding path for AC power during a power failure period of the system power supply 61.

  The energy management device 81 and the display terminal 82 are configured to be capable of wireless communication with each other. In response to a request from the display terminal 82, the display data generation unit 81c generates display information for causing the display terminal 82 to display the above information, the control states of the power converter 51 and the fuel cell 63, and the like. Transmit to the display terminal 82. The display terminal 82 displays the received display information on the screen, and also makes a voice notification if necessary. As the display terminal 82, a dedicated terminal having a monitor screen and a speaker, a mobile phone, a personal computer, or the like is used.

  Next, power control at the time of a power failure by the energy management device 81, which is the gist of the present invention, will be described with reference to the flowchart of FIG. In addition, the power consumption of the specific load 80 at the time of a power failure is the load power P0, the discharge power of the storage battery 62 is P2, the generated power of the fuel cell 63 is P3, the generated power of the solar battery 64 is P4, and the constraint output of the power converter 50 is Let Ps.

  When the power control unit 81b of the energy management device 81 detects a power failure based on the power failure information acquired by the information acquisition unit 81a, the power control unit 81b starts power supply to the specific load 80 using the generated power P4 of the solar cell 64. And the electric power control part 81b compares the load electric power P0 at the time of a power failure, and the restrictions output Ps of the power converter device 50 (S1). When the load power P0 is less than the constraint output Ps, the power control unit 81b compares the generated power P4 of the solar battery 64 with the load power P0 (S2). When the generated power P4 of the solar cell 64 exceeds the load power P0, the power control unit 81b determines whether or not the fuel cell 63 is generating power (S3). If the fuel cell 63 is generating power, the power control unit 81b transmits a power generation stop command to the fuel cell 63 to stop the power generation of the fuel cell 63 (S4). At this time, power is supplied to the specific load 80 using only the generated power P4 of the solar battery 64. That is, when the power control unit 81b can supply power to the specific load 80 using only the generated power P4 of the solar cell 64 during a power failure, the power control unit 81b stops the power generation of the fuel cell 63 and only the generated power P4 of the solar cell 64. Is used to supply power to the specific load 80.

  Next, the power control unit 81b determines whether or not the storage battery 62 is being charged using the generated power P4 of the solar battery 64 (S5). If there is surplus power of the solar cell 64 (surplus power that is not consumed by the specific load 80 in the generated power P4 of the solar cell 64), the storage battery 62 can be charged using this surplus power. If the charging of the storage battery 62 using the surplus power of the solar battery 64 has already been performed, the power control unit 81b continues to charge the storage battery 62. When the storage battery 62 is not being charged, the power control unit 81b transmits a charge start command to the power conversion device 50, and starts charging the storage battery 62 using surplus power of the solar battery 64 (S6).

  That is, the power control unit 81b charges the storage battery 62 using the surplus power of the solar cell 64 when the power is supplied to the specific load 80 using only the generated power P4 of the solar cell 64 during a power failure.

  And the electric power control part 81b judges whether the power recovery (energization state) was detected based on the power failure information which the information acquisition part 81a acquired (S7). If power recovery is not detected, power control unit 81b returns to step S1, and if power recovery is detected, power control during power failure ends.

  As described above, when power can be supplied to the specific load 80 using only the generated power P4 of the solar cell 64 during a power failure, the power control unit 81b stops the power generation of the fuel cell 63 and generates power of the solar cell 64. Electric power is supplied to the specific load 80 using only the electric power P4. Furthermore, the power control unit 81 b charges the storage battery 62 using the surplus power of the solar battery 64. Therefore, the generated power P4 of the solar battery 64 during a power failure can be used effectively. Further, by stopping the power generation of the fuel cell 63, the amount of heat stored in the hot water storage tank 632 (the amount of stored hot water, the hot water temperature) can be suppressed, so that the power that the fuel cell 63 can generate at night when the solar cell 64 cannot generate power. Can be secured sufficiently. That is, when power can be supplied to the specific load 80 using only the power generated by the solar battery 64 during a power failure, the power generation capacity of the entire system using each power generated by the fuel cell 63 and the solar battery 64 effectively. Can be used efficiently. In general, by using the solar cell 64 without using the fuel cell 63, the power generation cost can be reduced.

  In step S2, when the generated power P4 of the solar cell 64 is less than or equal to the load power P0, the power control unit 81b causes the fuel cell 63 to generate power (S8). If the fuel cell 63 is in the power generation stop state, the power control unit 81b transmits a power generation start command to the fuel cell 63 to start power generation of the fuel cell 63. If the fuel cell 63 is generating power, the power control unit 81b continues the power generation of the fuel cell 63.

  If the generated power P3 of the fuel cell 63 is equal to or higher than the load power P0, the power control unit 81b supplies power to the specific load 80 using only the generated power P3 of the fuel cell 63. Further, if the generated power P3 of the fuel cell 63 is less than the load power P0, the power control unit 81b uses the generated power P3 of the fuel cell 63 and at least a part of the generated power P4 of the solar cell 64 to specify Power is supplied to the load 80. The generated power P3 of the fuel cell 63 at this time is the total generated power that can be supplied by the fuel cell 63.

  As described above, when the generated power P4 of the solar cell 64 is equal to or less than the load power P0, the power control unit 81b gives priority to the generated power P3 of the fuel cell 63 over the generated power P4 of the solar cell 64, and the specific load 80 To supply. That is, the load power P0 is covered as much as possible by the generated power P3 of the fuel cell 63, and the shortage of power generated by the generated power P3 of the fuel cell 63 (the difference between the load power P0 and the generated power P3 of the fuel cell 63 [P0−P3 ]) Is supplemented with the generated power P4 of the solar cell 64.

  Next, the power control unit 81b compares the load power P0 with the sum of the generated power P3 of the fuel cell 63 and the generated power P4 of the solar cell 64 (referred to as total generated power [P3 + P4]) (S9). If the load power P0 is less than or equal to the total generated power [P3 + P4], the power control unit 81b performs the processes after step S5 described above. That is, if there is surplus power of the solar battery 64, the power control unit 81 b charges the storage battery 62 using the surplus power of the solar battery 64. Therefore, even when the generated power P4 of the solar battery 64 is equal to or less than the load power P0, the storage battery 62 is charged using the surplus power of the solar battery 64, so that the generated power P4 of the solar battery 64 can be used effectively. That is, the power efficiency of the entire system including charging of the storage battery 62 can be improved using the generated power of the solar battery 64 and the fuel battery 63.

  For example, the storage battery 62 may not be charged from the fuel cell 63 due to the system configuration. Therefore, when the generated power P4 of the solar cell 64 is less than or equal to the load power P0, the fuel cell 63 can cover the power consumption of the specific load 80 as much as possible, and the surplus power of the solar cell 64 is charged to the storage battery 62, thereby It becomes possible to use electric power efficiently. Further, when the solar cell 64 cannot generate power such as at night, the fuel cell 63 can cover the power consumption of the specific load 80. Further, even when the amount of heat stored in the hot water storage tank 632 becomes full, the fuel cell 63 can generate power again if the hot water stored in the hot water storage tank 632 is reduced.

  In step S9, when the load power P0 exceeds the total generated power [P3 + P4], the power control unit 81b transmits a discharge start command to the power conversion device 50 to start the discharge control of the storage battery 62 (S10). ). Then, the power control unit 81b sets the load power P0 as the sum [P2 + P3 + P4] of the total generated power [P3 + P4] of the fuel cell 63 and the solar cell 64 and the discharge power P2 of the storage battery 62 (referred to as maximum supply power [P2 + P3 + P4]). (S11).

  When the load power P0 is equal to or less than the maximum supply power [P2 + P3 + P4], the power consumption of the specific load 80 is covered by the discharge power P2 of the storage battery 62, the generated power P3 of the fuel cell 63, and the generated power P4 of the solar cell 64. And the electric power control part 81b judges whether the power recovery (energization state) was detected based on the power failure information which the information acquisition part 81a acquired (S7). If power recovery is not detected, power control unit 81b returns to step S1, and if power recovery is detected, power control during power failure ends.

  When the load power P0 exceeds the maximum supply power [P2 + P3 + P4], the device control unit 81d performs stop control of the specific load 80 (S12). This stop control stops the load power P0 to be equal to or less than the maximum supply power [P2 + P3 + P4] by stopping one or more specific loads 80 having a low preset priority among all the specific loads 80. The number of specific loads 80 to be stopped is determined according to the reduction amount of the load power P0. That is, when the load power P0 exceeds the maximum supply power [P2 + P3 + P4], the device control unit 81d performs the stop control of the specific load 80, thereby reducing the load power P0 below the maximum supply power [P2 + P3 + P4]. The device control unit 81d can perform wired communication or wireless communication with the specific load 80, and can control the operation (power on / off, operation start / stop, etc.) of the specific load 80. Further, the device control unit 81d may control not only the specific load 80 but also the operation of the general load 70.

  In step S1, when the load power P0 is equal to or greater than the constraint output Ps, the power control unit 81b sets the difference [P0−P3] obtained by subtracting the generated power P3 of the fuel cell P3 from the load power P0 as the constraint output Ps. Compare (S13).

  When the difference [P0−P3] is less than the constraint output Ps, the process proceeds to step S8, and the power control unit 81b causes the fuel cell 63 to generate power. That is, the power control unit 81b causes the fuel cell 63 to generate power so that the output (self-supporting output) of the self-supporting terminal 57 of the power conversion device 50 is less than the constraint output Ps. That is, the power control unit 81b determines that the sum [Ps + P3] of the constraint output Ps and the generated power P3 of the fuel cell 63 exceeds the load power P0 when the self-sustained output of the power conversion device 50 reaches the constraint output Ps (upper limit value). If so, the fuel cell 63 is caused to generate power. Therefore, when the load power P0 is equal to or greater than the constraint output Ps, the power supply to the specific load 80 can be stabilized by using the power generated by the fuel cell 63.

  If the difference [P0−P3] is greater than or equal to the constraint output Ps, the process proceeds to step S12, and the device control unit 81d performs stop control of the specific load 80. That is, when the self-supporting output of the power conversion device 50 reaches the restriction output Ps, the device control unit 81d performs stop control of the specific load 80, thereby reducing the self-sustained output of the power conversion device 50 to less than the restriction output Ps.

  In step S8 described above, the load power P0 is covered as much as possible by the generated power P3 of the fuel cell 63, and the insufficient power due to the generated power P3 of the fuel cell 63 is supplemented by the generated power P4 of the solar cell 64. And in step S5 which passed step S9 from step S8, the storage battery 62 is charged using the surplus electric power of the solar cell 64. FIG. And if the storage battery 62 will be in a full charge state, the electric power control part 81b will increase the ratio of the electric power P4 of the solar cell 64 among load electric power P0 in subsequent step S8, and a fuel cell among load electric power P0. It is preferable to reduce the ratio of 63 generated power P3.

  In this case, the generated power P4 of the solar cell 64 during a power failure can be used effectively. Further, by reducing the generated power P3 of the fuel cell 63, the amount of heat stored in the hot water storage tank 632 (the amount of stored hot water, hot water temperature) can be suppressed, so that the fuel cell 63 can generate power at night when the solar cell 64 cannot generate power. Power can be secured.

  When the amount of hot water stored in the hot water storage tank 632 exceeds the upper limit (hot water storage amount threshold) due to the power generation by the fuel cell 63, the display data generation unit 81c generates a notification signal and transmits the notification signal to the display terminal 82. The notification signal includes image information and audio information that request the consumer to use the hot water in the hot water storage tank 632. In this case, the display data generation unit 81c corresponds to a notification signal output unit.

  The display terminal 82 prompts the consumer to actively use hot water by displaying the image information of the notification signal on the screen and notifying the voice information. In this case, the amount of hot water to be used is preferably notified by the display terminal 82. And the amount of hot water stored in the hot water storage tank 632 is reduced by using hot water in the hot water storage tank 632 for floor heating, snow melting, bathing, and the like.

  Therefore, by discharging the hot water in the hot water storage tank 632, the amount of electric power that can be subsequently generated by the fuel cell 63 increases, and the power generated by the fuel cell 63 can be sufficiently secured.

  The fuel cell 63 preferably determines the amount of heat stored in the hot water storage tank 632 based on the amount of hot water stored in the hot water storage tank 632 and the temperature of hot water in the hot water storage tank 632. In this case, the heat storage amount of the hot water storage tank 632 is derived using both the hot water storage amount and the hot water temperature, and when the heat storage amount determined from both the hot water storage amount and the hot water temperature is full, the power generation unit 631. Power generation due to will stop. That is, the power generation unit 631 of the fuel cell 63 can generate power when the amount of hot water stored in the hot water storage tank 632 is not full or when the temperature of the hot water in the hot water storage tank 632 is equal to or lower than a predetermined temperature.

  The energy management device 81 includes a power control unit 81b that controls power supply to a specific load 80 (load) using the solar cell 64, the storage battery 62, and the fuel cell 63 (cogeneration device).

  The power control unit 81 b supplies the generated power of the fuel cell 63 to the specific load 80 when the generated power of the solar battery 64 is less than or equal to the power consumption of the specific load 80. Then, if the generated power of the fuel cell 63 is less than the power consumption of the specific load 80, the power control unit 81b determines the difference between the power consumption of the specific load 80 and the generated power of the fuel cell 63 as the generated power of the solar cell 64. compensate. Furthermore, the power control unit 81 b charges the storage battery 62 using surplus power that is not consumed by the specific load 80 among the generated power of the solar battery 64.

  The above-described energy management method is a power management method for controlling power supply to a specific load 80 (load) using the solar cell 64, the storage battery 62, and the fuel cell 63 (cogeneration device). When the generated power of the solar cell 64 is less than or equal to the power consumption of the specific load 80, the generated power of the fuel cell 63 is supplied to the specific load 80. Then, if the generated power of the fuel cell 63 is less than the power consumption of the specific load 80, the power control unit 81b determines the difference between the power consumption of the specific load 80 and the generated power of the fuel cell 63 as the generated power of the solar cell 64. compensate. Furthermore, the power control unit 81 b charges the storage battery 62 using surplus power that is not consumed by the specific load 80 among the generated power of the solar battery 64.

DESCRIPTION OF SYMBOLS 10 Distribution board 20 Self-supporting distribution board 30 Power supply switching device 40 Measuring apparatus 50 Power converter 61 System power supply 62 Storage battery 63 Fuel cell (cogeneration apparatus)
64 Solar cell 81 Energy management device 81a Information acquisition unit 81b Power control unit 81c Display data generation unit (notification signal output unit)
81d Device control unit 82 Display terminal

Claims (8)

A power control unit that controls power supply to a load using a solar cell, a storage battery, and a cogeneration device,
The power control unit
When the generated power of the solar cell is less than or equal to the power consumption of the load, the generated power of the cogeneration device is supplied to the load, and if the generated power of the cogeneration device is less than the power consumption of the load, Complement the difference between the power consumption of the load and the generated power of the cogeneration device with the generated power of the solar cell,
The storage battery is charged by using surplus power that is not consumed by the load among the generated power of the solar battery.   When the generated power of the solar cell exceeds the power consumption of the load, the power control unit supplies only the generated power of the solar cell to the load, and is consumed by the load among the generated power of the solar cell. The energy management apparatus according to claim 1, wherein the storage battery is charged using surplus power that is not used.   When the power generated by the solar battery is less than or equal to the power consumed by the load, the power control unit increases the proportion of the power generated by the solar battery out of the power consumed by the load when the storage battery is fully charged. The energy management apparatus according to claim 1, wherein a ratio of the generated power of the cogeneration apparatus is reduced in the power consumption of the load.   The said cogeneration apparatus produces | generates hot water at the time of electric power generation, and will stop electric power generation, if the heat storage amount of the hot water storage tank which stores this produced | generated hot water becomes more than predetermined amount, The power generation is stopped. Energy management device.   5. The energy management according to claim 4, further comprising: a notification signal output unit that outputs a notification signal that requests use of hot water in the hot water storage tank when the amount of heat stored in the hot water storage tank exceeds a threshold value. apparatus.   The power control unit converts the generated power of the solar battery and the generated power of the storage battery into alternating current power and supplies the load to the load so that the output of the power conversion device is less than an upper limit value. The energy management apparatus according to any one of claims 1 to 5, wherein power generation is controlled.   When the power consumption of the load is equal to or higher than the upper limit value of the output of the power conversion device, the power control unit is configured such that a difference obtained by subtracting the generated power of the cogeneration device from the power consumption of the load is the power conversion The energy management device according to claim 6, wherein if the output of the device is less than the upper limit value, power generation of the cogeneration device is started. A power management method for controlling power supply to a load using a solar cell, a storage battery, and a cogeneration device,
When the generated power of the solar cell is less than or equal to the power consumption of the load, the generated power of the cogeneration device is supplied to the load, and if the generated power of the cogeneration device is less than the power consumption of the load, Complement the difference between the power consumption of the load and the generated power of the cogeneration device with the generated power of the solar cell,
The storage battery is charged using surplus power that is not consumed by the load among the generated power of the solar battery.

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