JP2014072943A - Power generation system and power conditioner for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation system and a power conditioner for the power generation system capable of preventing an electric apparatus from malfunctioning or the like caused by lack of a power generation amount of a power generation unit when autonomous operation is performed.SOLUTION: A power generation system comprises: a photovoltaic power generation device 1; a power conditioner 3 having an autonomous operation function; and a hot water supplier 4 that receives power supply from an autonomous operation-dedicated outlet of the power conditioner 3, where a control unit 8 of the power conditioner is communicably connected to a control unit 13 of the hot water supplier. The control unit 8 of the power conditioner controls the hot water supplier 4 so as to be in a provisional operation state where only a freezing prevention heater 12 is activated, when detecting start up of the hot water supplier 4 after start of the autonomous operation; determines whether or not output voltage of the power conditioner 3 is maintained as planned in this state; and releases the provisional operation state of the hot water supplier 4 to make the hot water supplier 4 be in a state where the hot water supplier 4 is capable of normal act, when the output voltage is maintained without reduction.

Description

  The present invention relates to a power generation system and a power conditioner thereof, and more particularly to a self-sustaining operation function of a power conditioner during a power failure in a power system in a power generation system including a solar power generation device.

  Conventionally, a power conditioner of a solar power generation device has a self-sustaining function that enables the power generated by the solar power generation device to be used as an emergency power source when a power system such as a commercial power supply fails. Has been proposed.

  A power conditioner having such a self-sustaining operation function is provided with a dedicated power outlet (a self-sustained operation outlet) for supplying power generated by the solar power generation device to a predetermined electric device during the self-sustaining operation. In the self-sustained operation, by connecting an electrical device to this power outlet, the electric device connected to the power outlet can be supplied with the electric power generated by the solar power generator (for example, patent Reference 1).

Japanese Patent No. 4524840

  However, such a conventional configuration has the following problems, and improvements have been desired.

  That is, the power generation amount of the solar power generation device varies according to the amount of solar radiation that changes depending on the season, time zone, weather, and the like (that is, the power generation amount is not constant). On the other hand, whether or not the power generation amount of the power generation unit is the power generation amount necessary for operating the electric device cannot be known unless the electric device is connected to the outlet for exclusive use of independent operation. In other words, if the electrical equipment is not connected to the stand-alone operation outlet, current does not flow to the stand-alone operation outlet, so whether the power generation amount is sufficient before connecting the electrical equipment to the stand-alone operation outlet. I can't judge. Therefore, in the conventional power generation system, when an electric device is connected to the above-mentioned outlet for exclusive use of self-sustained operation when the amount of power generated by the solar power generation device is low, the electric power necessary for the operation of the electric device cannot be obtained and the electric device The operation may stop or malfunction, and there is a risk of causing damage or failure of the electrical equipment.

  The present invention has been made in view of such problems, and the object of the present invention is to prevent electrical equipment from malfunctioning due to a shortage of power generation by the power generation unit during autonomous operation. The purpose is to provide a power generation system and its power conditioner.

  In order to achieve the above object, a power generation system according to claim 1 of the present invention connects a power generation unit and power generated by the power generation unit to the power system, and at the time of power failure of the power system, A power conditioner that has a self-sustaining operation function that allows the generated power to be supplied to an external electrical device from a dedicated outlet for independent operation, and an electrical device that receives power supply from the exclusive outlet for independent operation during the independent operation of the power conditioner The power conditioner control unit is communicably connected to the control unit of the electric device, and detects the activation of the electric device after the start of independent operation. Control is made to a temporary operating state in which only the electric load operates, and the output voltage of the inverter is detected in this state. Output voltage, characterized in that it comprises a control arrangement for releasing the provisional operation status when a predetermined voltage or more.

  In the power generation system according to the first aspect, the autonomous operation of the power conditioner is started, and accordingly, power supply to the electric device connected to the outlet for exclusive use of the independent operation is started (that is, the electric device is activated). And the control part of a power conditioner controls the said electric equipment to a temporary driving | running state. This provisional operation state is an operation mode in which only a part of the electric load in the electric device is operated, and the control unit of the power conditioner is in a state in which only a part of the electric load of the electric device is operated in this way. Then, it is judged by comparing with the predetermined voltage whether the output voltage of the inverter is maintained as planned (in other words, whether the rated output voltage of the outlet for exclusive use of independent operation is maintained). In other words, if the detected output voltage is equal to or higher than the predetermined voltage, it is determined that the expected output voltage is maintained. Release the state. Thereby, the electric device connected to the outlet for exclusive use of independent operation can operate as usual.

  Here, the `` predetermined electrical load '' that is operated in the provisional operation state is an electrical load that is not dangerous even if the operation is stopped due to a shortage of the power generation amount of the power generation unit during the provisional operation, and An electric load that consumes a large amount of power during operation, that is, an electric load that easily affects the output voltage of the power conditioner (for example, an electric heater) is preferably employed.

  As described above, in the power generation system according to claim 1, when the power conditioner starts the autonomous operation, the electric device performs the temporary operation, and predicts whether the power generation amount of the power generation unit is sufficient in this state, Temporary operation is canceled when it is expected to be sufficient, so it is unlikely that electrical equipment that has been provisionally operated and can be operated normally will experience power shortage, and start independent operation It is possible to provide a power generation system that is less likely to cause damage or failure of electrical equipment.

  A power generation system according to a second aspect of the present invention is the power generation system according to the first aspect, wherein the control unit of the power conditioner controls the electric device according to an input voltage on the power generation unit side of the power conditioner. It is characterized by having a control configuration for restricting or releasing the control of the control unit.

  In the power generation system according to claim 2, whether or not the control unit of the power conditioner has a margin in the power generation amount of the power generation unit from the input voltage on the power generation unit side of the power conditioner (that is, the output voltage of the power generation unit). Judging. For example, when the input voltage of the inverter is low, it is determined that the amount of power generation is “no margin” or “low margin”, and the control unit of the electric device is restricted (for example, during operation) The current state of the electric load and the stoppage of a part or all of the operating electric load, etc.) are requested to avoid / eliminate the shortage of power generation. On the other hand, if the input voltage of the inverter is high, the power generation amount is judged to be “surplus”, and if there is a restriction that is being implemented, the controller of the electric device is requested to cancel it. Allow an increase in power consumption on the device side.

  In this way, in the power generation system according to claim 2, since the control unit of the power conditioner requests a restriction on the control of the electric device according to the input voltage of the power conditioner or requests the removal of the restriction, It is avoided / eliminated that the electrical equipment falls short of power during the independent operation of the conditioner.

  In a power generation system according to a third aspect of the present invention, in the power generation system according to the second aspect, the limitation of the control of the electric load includes a control for reducing an operation amount per unit time of the electric load. It is characterized by that.

  In the power generation system according to the third aspect, since the control of the control unit of the electric device includes the control to reduce the operation amount per unit time of the electric load, when such control is performed, the electric load The temporary increase in power consumption due to the rapid operation of the power supply is mitigated, and it is possible to prevent the electric device from falling short of power.

  A power generation system according to a fourth aspect of the present invention is the power generation system according to any one of the first to third aspects, wherein the electric device is a water heater. That is, in the power generation system according to the fourth aspect, since the water heater is connected to the outlet for exclusive use of the independent operation of the power conditioner, the water heater can be used even when the power system is interrupted.

  The power generation system according to claim 5 of the present invention is characterized in that, in the power generation system according to claim 4, the electric load that operates in the provisional operation state is an electric heater for preventing freezing. That is, in the power generation system according to the fifth aspect, only the electric heater for preventing freezing provided in the water heater is operated by the temporary operation accompanying the start of the self-sustained operation. Even if the operation stops, the hot water supply performance of the water heater is hardly impaired, so that it is avoided that the operation of the water heater is hindered when the power system is restored.

  A power conditioner according to a sixth aspect of the present invention is a power conditioner applied to the power generation system according to any one of the first to fifth aspects, wherein the electric power generated by the power generation unit is linked to the power system. In a power conditioner having a self-sustaining operation function that enables power generated by the power generation unit to be supplied to an external electrical device from an outlet dedicated for self-sustaining operation when a power failure occurs in the power system, the control unit of the power conditioner It is configured to be communicable with the control unit of the electric device, and when activation of the electric device is detected after the start of independent operation, the electric device is controlled to a temporary operation state in which only a predetermined electric load operates, and in this state, the power A control configuration is provided that detects the output voltage of the conditioner and cancels the provisional operation state if the output voltage is equal to or higher than a predetermined voltage. And wherein the Rukoto.

  According to the present invention, when the power conditioner starts a self-sustained operation, a provisional operation is performed in which only a part of the electric load of the electrical equipment connected to the power conditioner self-sustained operation outlet is operated. In addition to predicting whether the power generation amount of the power generation unit is sufficient for the operation of the electric device, and if the power generation amount of the power generation unit is sufficient, the control unit of the power conditioner cancels the provisional operation of the electric device, At least, it is avoided that the electric device connected to the outlet for exclusive use of the independent operation at the beginning of the autonomous operation falls into a power shortage, and the electric device is prevented from malfunctioning due to the power shortage.

  During the independent operation, the control unit of the power conditioner limits or cancels the control of the electrical equipment according to the input voltage of the power conditioner. Even within, it is avoided / eliminated that electric equipment falls into power shortage.

It is a block circuit diagram which shows an example of schematic structure of the electric power generation system which concerns on this invention. It is a flowchart which shows an example of the control procedure of the control part of the power conditioner at the time of the self-sustained operation start of the power generation system. It is explanatory drawing which shows an example of the output characteristic of a solar power generation device. It is a flowchart which shows an example of the control procedure of the control part of the power conditioner during the self-sustained operation of the power generation system. It is a flowchart which shows an example of the control procedure of the control part of the water heater during the self-sustained operation of the power generation system.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Embodiment 1
FIG. 1 shows a schematic configuration of a power generation system according to the present invention. The power generation system shown in FIG. 1 is a power generation system including a solar power generation device 1 as a power generation unit, and uses the solar power generation device 1 and the power generated by the solar power generation device 1 as a power system (for example, , A power conditioner 3 for connecting to a single-phase AC 100V or a single-phase AC 200V commercial power source 2), and a water heater that operates using the power generated by the photovoltaic power generator 1 when the power system 2 is interrupted as a power source (Electrical equipment) 4 is configured as a main part.

  As is well known, the solar power generation device 1 includes a solar power generation panel configured to obtain a necessary voltage by connecting a plurality of solar cells (cells) in series and parallel. It is configured by being installed in a place with good sunlight conditions (for example, on a roof or a veranda).

  The power conditioner 3 is a grid-connected inverter device that converts the DC power generated by the photovoltaic power generation device 1 into AC power that can be linked to the power system 2, and the DC power generated by the photovoltaic power generation device 1. A converter unit (DC / DC converter) 5 that boosts power, an inverter unit (DC / AC inverter) 6 that converts DC power boosted by the converter unit 5 into AC power that can be linked to the power system 2, and an inverter Each part of the power conditioner 3 such as a grid connection relay 7 which is a relay for supplying the AC power converted by the section 6 to the power system 2, and the operations of the converter unit 5, the inverter unit 6 and the grid connection relay 7. And a control unit 8 that controls the main part.

  In addition to the basic configuration as the grid-connected inverter device, the power conditioner 3 shown in the present embodiment converts the power generated by the solar power generation device 1 at the time of a power failure of the power system 2 to an external electrical device (this In the embodiment, a stand-alone operation outlet 9 for supplying to the water heater 4) and the AC power converted by the inverter unit 6 during the self-operation of the power conditioner 3 are connected to the stand-alone operation outlet 9. And a relay for independent operation 10 that is a relay of the above.

  In other words, the power conditioner 3 has a self-sustaining operation function, and the control unit 8 closes the contact of the grid interconnection relay 7 when the power system 2 is normal (that is, the power system 2 is not out of power). The inverter unit 6 and the power system 2 are connected to connect the photovoltaic power generation apparatus 1 and the power system 2. On the other hand, when the power system 2 fails, the contact of the grid connection relay 7 is opened and the inverter unit 6 is connected. While disconnecting from the power system 2, the contact of the independent operation relay 10 is closed and the inverter unit 6 and the independent operation outlet 9 are connected, so that the electric power generated by the photovoltaic power generator 1 is used as the independent operation outlet 9. (I.e., autonomous operation).

  Note that a relay with a normally open contact is used for the self-sustained operation relay 10, and the contact is open when the power system 2 is normal. That is, the stand-alone operation outlet 9 is configured as a power outlet used only when the power conditioner 3 performs the stand-alone operation. Further, in the illustrated example, the case where the independent operation dedicated outlet 9 is provided in the power conditioner 3 is shown. However, the independent operation dedicated outlet 9 may be provided outside the power conditioner 3. Good.

  The power conditioner 3 is provided with a power supply unit (not shown) in addition to these, and this power supply unit is solar when the power system 2 is normal (when the power system 2 is not out of power). While receiving power supply from the photovoltaic power generation device 1 or the power system 2 and supplying driving power to each part of the power conditioner 3, when the power system 2 is out of power, it receives power supply from the solar power generation device 1 and power condition. The driving power is supplied to each part of the na 3. In addition, the power conditioner 3 includes a display unit (not shown).

  The hot water heater 4 is a hot water supply device that heats and raises water supplied from a water source such as city water to hot water having a hot water supply set temperature and supplies the hot water tap to the hot water tap. Although description is omitted, as shown in FIG. 1, the hot water heater 4 includes a freezing prevention heater 12 including at least a combustion section 11 having a burner and an electric heater for preventing freezing of a pipe through which water flows. And a control unit 13 that controls each part of the water heater including the combustion unit 11 and the freeze prevention heater 12, and a power source unit 14 that supplies driving power to each part of the water heater. In addition, each part which comprises this water heater 4 is equipped with the various electric load which uses electricity as a drive source including the said anti-freezing heater 12.

  And in this embodiment, the control part 13 of the water heater 4 and the control part 8 of the power conditioner 3 which are comprised in this way are connected so that communication is possible. That is, the control unit 8 of the power conditioner 3 and the control unit 13 of the water heater 4 are communicatively connected via the communication line 15, and the control unit 8 of the power conditioner 3 controls the water heater 4 as described later. Various controls are performed on the unit 13.

Next, the operation | movement at the time of the independent operation in the electric power generation system comprised in this way is demonstrated.
FIG. 2 shows a procedure when the power system 2 is interrupted and the power conditioner 3 starts the independent operation.

  Since the power conditioner 3 shown in the present embodiment has the self-sustaining operation function as described above, when the power system 2 fails, the control unit 8 of the power conditioner 3 detects the power system 2 power failure. Then, independent operation is started (see step S1 in FIG. 2). In this self-sustained operation, the control unit 8 first operates the inverter unit 6. As a result, the DC power generated by the photovoltaic power generator 1 and boosted by the converter unit 5 is supplied to the inverter unit 6, and the AC power (for example, general It is converted into AC 100V, which is a household AC power source.

  When the inverter unit 6 operates, the control unit 8 next closes the contact of the autonomous driving relay 10 (turns it ON) and connects the independent operation outlet 9 to the inverter unit 6 (see step S2 in FIG. 2). As a result, the AC power generated by the inverter unit 6 is supplied to the independent operation outlet 9. At this time, the control unit 8 opens the contact of the grid interconnection relay 7, and the inverter unit 6 is disconnected from the power system 2.

  In this way, when AC power is supplied to the independent operation dedicated outlet 9, the outlet 9 can be used. In this state, the power supply unit 14 of the water heater 4 is connected to the independent operation dedicated outlet 9. Then, the electric power generated by the solar power generator 1 is supplied to the water heater 4 (see step S2 in FIG. 2). That is, in order for the water heater 4 to receive power supply from the outlet 9 dedicated to independent operation, a power plug (not shown) provided in the power supply unit 14 of the water heater 4 is connected to a household power outlet (see FIG. It is necessary to change from the not-shown outlet 9 to the outlet 9 dedicated to independent operation.

  When the power supply unit 14 of the water heater 4 is connected to the independent power outlet 9 and power is supplied to the power supply unit 14 of the water heater 4, the control unit 13 of the water heater 4 activated by the power supply unit 14 is connected to the power conditioner 3. Communication with the control unit 8 is started. The control unit 8 of the power conditioner 3 is started by communication with the control unit 13 of the water heater 4 during the self-sustaining operation, so that the water heater 4 is activated by the electric power supplied from the outlet 9 dedicated to the self-sustaining operation. (In other words, it is detected that the power supply from the outlet 9 dedicated for independent operation to the water heater 4 has started).

  When the water heater 4 is activated in this way, the control unit 8 of the power conditioner 3 next notifies the control unit 13 of the water heater 4 that the power conditioner 3 is operating independently. The water heater 4 is set to a predetermined self-sustaining operation mode, and the water heater 4 is controlled to a temporary operation state in which only a predetermined electric load operates.

  Here, the provisional operation of the water heater 4 is performed in order to determine whether or not the amount of power generated by the solar power generator 1 is sufficient to operate the water heater 4, as will be described later. In this embodiment, the control to the temporary operation state is performed from the control unit 8 of the power conditioner 3 to the hot water heater 4. This is performed by issuing an operation command for operating only the freeze prevention heater 12 (turning on the electric heater) to the control unit 13 (see step S3 in FIG. 2).

  Here, in this embodiment, the freeze prevention heater 12 is used as an electric load to be operated in the provisional operation state of the water heater 4 because of the insufficient power generation amount of the solar power generation device 1 when the provisional operation is performed. There is no danger even if the operation of the freeze prevention heater 12 is stopped, and the freeze prevention heater 12 consumes a relatively large amount of power during operation, and confirms the amount of power generation based on the output voltage Vpcout of the power conditioner 3 described later. This is based on reasons such as what can be done more accurately. Therefore, as long as the electrical load satisfies such conditions, it is possible to configure the electrical load other than the freeze prevention heater 12 to operate in the provisional operation.

  Further, in the present embodiment, when controlling the water heater 4 to the temporary operation state, the electric load to be operated with respect to the control unit 13 of the water heater 4 is designated and an operation command is issued. For example, an electric load to be operated in the provisional operation is set in the control unit 13 of the water heater 4 in advance, and the control unit 8 of the power conditioner 3 instructs only the start of the provisional operation to the control unit 13 of the water heater 4. You may comprise. Therefore, for example, the notification that the above-described autonomous operation is being performed is used as a temporary operation start command, and the control unit 13 of the water heater 4 that has received the notification may automatically start the temporary operation. Is possible.

  When the water heater 4 starts the provisional operation, the control unit 8 outputs the output voltage of the power conditioner 3 (that is, the output voltage of the inverter unit 6) Vpcout in this state, that is, when the water heater 4 is in the provisional operation state. Is detected, and it is determined whether or not the detected output voltage Vpcout is equal to or higher than a predetermined voltage (AC101V in this embodiment) A (see step S4 in FIG. 2). Here, the predetermined voltage A used for this determination is set based on an AC voltage (AC 100 V in the present embodiment) output from the independent operation-only outlet 9. In this embodiment, this determination is based on whether the output voltage Vpcout of the power conditioner 3 can maintain the predetermined voltage A or not. Judging by.

  As a result of this determination, when the output voltage Vpcout of the power conditioner 3 is equal to or higher than the predetermined voltage A (a state equal to or higher than the predetermined voltage A can be maintained), the controller 8 determines the temporary operation state of the water heater 4. Control to release Specifically, an operation command for stopping the operation of the freeze prevention heater 12 (turning off the electric heater) is output from the control unit 8 to the control unit 13 of the water heater 4 (see step S5 in FIG. 2).

  Thereby, the control part 4 of the water heater 4 stops the operation of the freeze prevention heater 12 and returns to the normal operation (normal operation) from the temporary operation state (see step S6 in FIG. 2). That is, the water heater 4 returns to a state where it can perform an operation according to an operation of a remote controller (not shown). At this time, when the operation restriction in the independent operation mode is set in the control unit 13 of the water heater 4, the control unit 13 of the water heater 4 controls the operation of the water heater 4 according to the operation restriction.

  On the other hand, when the output voltage Vpcout of the power conditioner 3 is less than the predetermined voltage A (the predetermined voltage A cannot be maintained) as a result of the determination in step S4 in FIG. While opening the contact of the relay 10, the operation of the inverter unit 6 is stopped, and a display indicating that the generated power is insufficient is displayed on a display unit (not shown) provided in the power conditioner 3 (step in FIG. 2). (See S7).

  Then, after a certain time has passed (see step S8 in FIG. 2), the processing from step S1 in FIG. 2 is started again. This is because the amount of power generated by the solar power generation device 1 increases or decreases depending on the amount of solar radiation that changes depending on the time of day or the weather, and it is determined again whether the amount of power generated has increased after a certain period of time. .

  As described above, in the power generation system of the present embodiment, when the power conditioner 3 starts the independent operation, a part of the electric load (freezing prevention heater) is applied to the water heater 4 connected to the independent operation dedicated outlet 9. 12) Whether or not the provisional operation for operating only the power supply is performed, and whether or not the control unit 8 of the power conditioner 3 has enough power to operate the water heater 4 during the provisional operation. When the power generation amount is determined to be sufficient, the hot water heater 4 is shifted to a normal operation, so that the power generation amount of the solar power generation device 1 is insufficient at the start of independent operation. Thus, the operation (normal operation) of the water heater 4 is avoided.

  Next, the control of the control unit 8 of the power conditioner 3 and the control of the control unit 13 of the water heater 4 after the start of independent operation will be described. Here, FIG. 3 shows the output characteristics of the photovoltaic power generator 1, FIG. 4 shows the control procedure of the control unit 8 of the power conditioner 3 during the independent operation, and FIG. 5 shows the water heater during the independent operation. 4 shows a control procedure of the control unit 13.

  As shown in FIG. 3, when this type of photovoltaic power generation apparatus 1 increases the output voltage, the output power has a relationship of decreasing with the maximum power point voltage Vpmax being the maximum (Pmax). Therefore, in the power generation system shown in the present embodiment, using such output characteristics of the solar power generation device 1, the control unit 8 of the power conditioner 3 outputs the output voltage of the solar power generation device 1 during self-sustained operation, that is, The input voltage (input voltage of the converter unit 5) Vpcin on the photovoltaic power generator 1 side of the power conditioner 3 is monitored, and it is determined whether there is a margin in the generated power according to this input voltage Vpcin. Based on the result, the control of the control unit 13 of the water heater 4 is restricted as necessary, or the restriction is released.

  Specifically, the control unit 8 of the power conditioner 3 generates the generated power when the input voltage Vpcin of the power conditioner 3 is higher than the maximum power point voltage Vpmax by a certain value α (when Vpmax + α ≦ Vpcin). When the input voltage Vpcin is near the maximum power point voltage Vpmax (when Vpmax ≦ Vpcin <Vpmax + α), it is determined that the generated power has a small margin and the input voltage Vpcin is at the maximum power point. When the voltage is lower than the voltage Vpmax (when Vpcin <Vpmax), it is determined that the generated power has no margin (the generated power is insufficient). Here, the constant value α is an arbitrary value set to determine the margin of the generated power, and this value is appropriately set according to the output characteristics of the solar power generation device 1.

  And the control part 8 of the power conditioner 3 is comprised so that control of the hot water heater 4 may be restrict | limited or the restriction | limiting may be cancelled | released in the following procedures on the assumption that such a determination is performed during independent operation. Yes.

  That is, when the water heater 4 starts normal operation (see step S6 in FIG. 2) under the self-sustaining operation, the control unit 8 detects the input voltage Vpcin of the power conditioner 3 at a constant period, and the solar power generator 1 It is determined whether there is a margin in the amount of power generation (see step S1 in FIG. 4).

  If it is determined that there is no margin in the generated power (Yes in step S2 in FIG. 4), the control unit 8 of the power conditioner 3 supplies hot water to the control unit 13 of the water heater 4. An instruction to reduce the operation amount of the device 4 (an instruction to limit control) is output (see step S3 in FIG. 4 and step S1 in FIG. 5).

  When the control unit 13 of the water heater 4 receives an instruction to reduce the amount of operation, the control unit 13 performs control to stop part or all of the operating electric load (see step S2 in FIG. 5). For example, the water heater 4 has a hot water supply function (a function for supplying hot water to the hot water tap), a bath function (a hot water filling function for a bathtub or a warm water retaining function in the bathtub), and a heating function (for supplying hot water to the hot water heater). If the function is provided, the control unit 13 of the water heater 4 stops some or all of these functions during operation.

  Here, which function is to be stopped when this instruction is received is appropriately set in the control unit 13 of the water heater 4, but preferably, even if the function is stopped, the user (user) of the water heater 4 is affected. It is set to reduce the operation sequentially from few functions. For example, when all the functions of hot water supply, bath and heating are in operation, the heating function is stopped while leaving the hot water and bath functions (maintaining these operations). In addition, when the hot water supply and bathing functions are in operation, only the hot water supply function is left and the bathing function is stopped and the heating function is prohibited (where the prohibition is the operation start operation with a remote control etc.) Means that the operation is not performed (the same applies hereinafter). Furthermore, when only the hot water supply function is operating, a method of stopping the operation of the hot water supply function and prohibiting the operation of the bathroom and the heating function may be employed. In addition, when stopping the function in operation in this way, of course, it is also possible to comprise so that several functions (for example, both a bathroom and heating) may be stopped simultaneously.

  On the other hand, when it is determined that the generated power has a small margin (Yes in step S4 in FIG. 4), the control unit 8 controls the operation amount of the water heater 4 with respect to the control unit 13 of the water heater 4. Is output (instruction for restricting control) (see step S5 in FIG. 4, step S3 in FIG. 5).

  When the holding of the operation amount is instructed, the control unit 13 of the water heater 4 controls the water heater 4 so that the electric load during operation does not increase (see step S4 in FIG. 5). For example, in a state in which this instruction is received, even if the user performs an operation to increase the function being operated with the remote controller of the water heater 4 or the like, the control unit 13 does not accept the operation and accepts an operation to reduce the function being operated. Control to reduce the function that operates. For example, the control unit 13 of the water heater 4 is configured not to perform the operation of the bath function even when the operation of the bath function (for example, the bath water filling function) is requested while only the hot water function is operating. Is done.

  Note that the control of the water heater 4 when the holding of the operation amount is instructed requires the function in operation when an operation of a function having a larger influence on the user than the function in operation is requested. Control of temporarily stopping and operating the requested function may be included. For example, when an operation of the hot water supply function is requested during the operation of the bath function (for example, during filling of the bath bath), the bath function is temporarily stopped and the hot water supply function is operated. You can also.

  On the other hand, when it is determined that the generated power has a margin (No in step S4 in FIG. 4), the control unit 8 of the power conditioner 3 controls the control unit 13 of the water heater 4. Then, an instruction to loosen (release the restriction) the operation amount of the water heater 4 is output (see step S6 in FIG. 4 and step S5 in FIG. 5).

  When an instruction to loosen the operation amount is given, the control unit 13 of the water heater 4 permits the operation amount of the water heater 4 to increase. Thus, for example, if there is an operation request for the heating function while the hot water supply function and the bath function are operating, the heating function is also operated in addition to the hot water supply and bath functions.

  In addition, the control unit 8 of the power conditioner 3 monitors whether or not the power failure of the power system 2 has been restored at all times or periodically during such independent operation, and when the power failure recovery is detected. The notification means (for example, a display unit) provided in either the power conditioner 3 or the remote controller notifies the user of the fact and also performs a predetermined autonomous operation stop operation (for example, the illustration provided in the power conditioner) to the user. (Predetermined operation on the operation unit not to be performed). Then, when the user performs a self-sustained operation stop operation, the self-sustained operation is stopped. That is, when the self-sustained operation is stopped, the contact of the self-sustained operation relay 10 is opened and the self-sustained operation outlet 9 is disconnected from the inverter unit 6, and the contact of the grid interconnection relay 7 is closed so that the inverter unit 6 is connected to the power system. Connect to 2.

  And when independent operation stops (when it becomes Yes in FIG.4 step S7), since the electric power supply to the hot water heater 4 via the independent electrical operation outlet 9 is cut off, the control part 13 of the hot water heater 4 stops, At the same time, all control restrictions (including control restrictions associated with the self-sustaining operation mode) of the water heater 4 are released (see step S8 in FIG. 4).

  Thus, in the power generation system shown in the present embodiment, the control unit 8 of the power conditioner 3 limits the control of the water heater 4 according to the input voltage Vpcin of the power conditioner 3 during the self-sustaining operation, or Since the restriction is removed, it is avoided / eliminated that the water heater 4 falls short of electric power during the independent operation.

Embodiment 2
Next, a second embodiment of the present invention will be described.
In the power generation system shown in the second embodiment, the control content of the control unit 13 of the water heater 4 in the first embodiment is modified. Specifically, when the control unit 8 of the power conditioner 3 determines that “there is no margin” or “the margin is small” in the power generation amount of the photovoltaic power generation apparatus 1 during the independent operation (steps S2 and S4 in FIG. 4). The content of the restriction of the control of the water heater 4 in the reference) is modified.

  That is, in the power generation system shown in this embodiment, it is performed when the control unit 8 of the power conditioner determines that “there is no margin” or “the margin is small” in the power generation amount of the photovoltaic power generation apparatus 1 during the independent operation. The limitation of the control of the water heater 4 (see steps S2 and S4 in FIG. 5) includes control for reducing the operation amount per unit time of the electric load of the water heater 4.

  That is, when the water heater 4 realizes the function as the water heater, various electric loads (for example, proportional valves for controlling the amount of fuel supplied to the burner, water heater 4 to each part of the water heater 4 are electrically driven). A flow rate control valve that controls the amount of incoming water and the amount of hot water discharged from the water heater, a blower fan that sends combustion air to the combustion section 11, a pump that circulates hot water in the pipe, and the like. Most of the electrical loads have an operation amount per unit time at the time of operation in relation to the hot water characteristics.

  In the power generation system shown in the present embodiment, in the operation control of such an electric load driven by electricity, the power generation amount of the photovoltaic power generation apparatus 1 is “no margin” or “no margin” in the control unit 8 of the power conditioner 3. When it is determined that the amount is “low” (in other words, when the control of the water heater 4 is restricted), the control unit 13 of the water heater 4 per unit time when operating these electric loads. It is configured to perform control to reduce the operation amount from the normal time (that is, to delay the response speed of the electric load).

  Therefore, when this control is executed, for example, even if an operation for raising the hot water supply set temperature is performed with a remote controller or the like, the hot water temperature from the water heater 4 rises more slowly than usual.

  As described above, in the power generation system shown in the present embodiment, when it is determined that the power generation amount of the photovoltaic power generation apparatus 1 is “no allowance” or “no allowance” during the independent operation, the electric load driven by electricity Is operated more slowly (slowly) than usual, so that power consumption at the electric load during operation is suppressed, and it is avoided that the water heater 4 falls short of power due to sudden additional fluctuations.

  The above-described embodiments show preferred embodiments of the present invention, and the present invention is not limited to these, and various design changes can be made within the scope of the invention.

  For example, in the above-described embodiment, the case where the hot water heater 4 is used as an electric device that receives power supply from the outlet 9 dedicated to the independent operation of the power conditioner 3 is illustrated. An electrical device other than the container 4 may be used.

  Moreover, although the case where the solar power generation device 1 was used as the power generation unit was shown in the above-described embodiment, the power generation unit may use a power generation device of another aspect such as a fuel cell power generation device as long as the power generation unit can generate power in-house. It is.

  Further, in the above-described embodiment, the operation amount of the water heater 4 is reduced or held when it is determined that the power generation amount of the solar power generation device 1 is “no margin” or “less margin” during the independent operation. For example, it is configured to notify the situation such as “insufficiently generated power generated by self-sustained operation” or “restricting control of the water heater” through the display of the remote controller of the water heater 4 along with these controls. It is also possible to keep it. Moreover, it may be configured to notify that it is “in a self-sustaining operation” or “a provisional operation state”.

DESCRIPTION OF SYMBOLS 1 Solar power generation device 2 Electric power system 3 Power conditioner 4 Water heater 5 Converter part 6 Inverter part 7 Grid connection relay 8 Control part (control part of a power conditioner)
9 Stand-alone outlet 10 Stand-alone operation relay 11 Combustion section 12 Freezing prevention heater (electric load)
13 Control unit (control unit for electrical equipment)
14 Power supply 15 Communication line

Claims (6)

A self-supporting power generator that connects the power generated by the power generating unit to an electric power system and that can supply the electric power generated by the power generating unit to an external electrical device from a stand-alone outlet for independent operation when a power failure occurs. In a power generation system composed of a power conditioner having an operation function and an electric device that receives power supply from the outlet for exclusive use of the independent operation during the independent operation of the power conditioner,
The control unit of the power conditioner is connected to the control unit of the electric device so as to be communicable, and when the activation of the electric device is detected after the start of independent operation, the electric device operates only in a predetermined electric load. And a control structure for detecting the output voltage of the power conditioner in this state and canceling the provisional operation state if the output voltage is equal to or higher than a predetermined voltage.   The control unit of the power conditioner includes a control configuration that restricts or removes the control of the control unit of the electric device according to the input voltage on the power generation unit side of the power conditioner. The power generation system according to claim 1.   The power generation system according to claim 2, wherein the control restriction of the control unit of the electric device includes control for reducing an operation amount per unit time of the electric load.   The power generation system according to claim 1, wherein the electric device is a water heater.   The power generation system according to claim 4, wherein the electric load that operates in the temporary operation state is an electric heater for preventing freezing. In addition to linking the power generated by the power generation unit to the power system, the power generation unit has a self-sustaining operation function that enables power generated by the power generation unit to be supplied to an external electrical device from a power outlet dedicated to self-sustained operation. In the inverter
The control unit of the power conditioner is configured to be communicable with the control unit of the electric device, and when the activation of the electric device is detected after the start of independent operation, the electric device operates only in a predetermined electric load. And a control configuration for detecting the output voltage of the power conditioner in this state and canceling the provisional operation state if the output voltage is equal to or higher than a predetermined voltage. .

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