JP2016123241A - Power conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conditioner for constantly supplying power to a load without involving complication of wiring.SOLUTION: A power conditioner 1 comprises: a first input part IN1 to which a power system 101 is connected; a second input part IN2 to which a photovoltaic power generation panel 102 is connected; and an output part OUT to which a power distribution board 103 is connected. A switch element S1 is provided between the first input part IN1 and the output part OUT. A DC/AC inverter 11 is provided between the second input part IN2 and the output part OUT. The switch element S1 is turned on at a normal time other than an outage time and is turned off at the outage time.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power conditioner that performs power control of a system including a power system and a generator.

  In a solar power generation system that uses electric power generated by a generator, such as a solar panel, in a home environment, a stand-alone outlet may be provided separately from a normal home outlet. This stand-alone outlet is not allowed to operate the power conditioner while it is connected to the power system in the event of a power outage. It is provided as a different route from the power system in order to use the remaining power. However, when the user uses this independent outlet, the user himself / herself needs to connect a load (for example, an electrical appliance) connected to the household outlet to the independent outlet. Further, since it is assumed that a load connected to a household outlet is normally connected, the power supply is also limited to 1500 W or less.

  Patent Document 1 discloses a power distribution system that eliminates the need to change the load to a self-supporting outlet. The power distribution system described in Patent Literature 1 includes a power conditioner that converts electric power generated by a solar panel into electric power that can be used in a home environment, a distribution board, and a switch that switches a power feeding path. The distribution board is supplied with power from the power conditioner and the commercial power system. During the grid operation with the commercial power system, the switch is switched so that the power conditioner and the commercial power system and the load are connected via the distribution board. During the independent operation, the power conditioner and the load are directly connected. Switch the switch so that it is connected. As a result, even if the power conditioner is operating independently due to a power failure or the like, power is supplied to each load, so that an independent outlet is not necessary, and the user does not have to reconnect the load to the independent outlet.

JP2013-90455A

  However, Patent Document 1 requires a switch for switching the connection between the load and the power source, and also requires a power supply path for supplying power to each load during the self-sustained operation, resulting in complicated wiring. is there.

  Therefore, an object of the present invention is to provide a power conditioner that can supply power to the load from the same output terminal as that during grid connection without complicating wiring.

  The power conditioner according to the present invention includes a first input unit that inputs AC power, a second input unit that inputs DC power, an output unit that outputs AC power, and a DC input from the second input unit. An inverter that converts electric power into AC power; a first path that electrically connects the first input section and the output section; a second path that electrically connects the inverter and the output section; A first switch element that is provided in the first path and electrically connects or disconnects the first path; and an input monitoring unit that monitors whether AC power is input from the first input unit; A control unit that turns on the first switch element when AC power is input from the first input unit, and that turns off the first switch element when AC power is not input from the first input unit. It is characterized by having

  In this configuration, when AC power is input from the first input unit, AC power from the first input unit is output from the output unit, and when AC power is not input from the first input unit, output is performed. From the unit, AC power obtained by converting DC power from the second input unit is output without an electrical connection with the first input unit. Thereby, AC power can be supplied to the load connected to the output unit of the power conditioner regardless of whether or not AC power is input to the first input unit, and when AC power is not input to the first input unit, The electric power output from the inverter does not flow out to the first input unit.

  The power conditioner according to the present invention includes a second switch element that is provided in the second path and electrically connects or disconnects the second path, and an abnormality detection unit that detects an abnormality of the inverter, Preferably, the control unit turns off the second switch element when the abnormality detection unit detects an abnormality.

  In this configuration, when the inverter fails, the second input unit and the output unit are short-circuited, and direct current power input from the second input unit can be prevented from being output from the output unit.

  In the power conditioner according to the present invention, the first path and the second path are connected to the output section by connecting one ends of the first switch element and the second switch element on the output section side. And a third switch element provided between a connection point of the first switch element and the second switch element and the output unit, and the control unit detects that the abnormality detection unit is abnormal. When detected, it is preferable to turn off the second switch element and the third switch element.

  In this configuration, even if the second switch element is short-circuit broken, the third switch element is turned off to prevent the second input unit and the output unit from being short-circuited when the inverter fails. Can do.

  The power conditioner according to the present invention includes an input / output unit to which a storage battery is connected, a PV converter provided between the second input unit and the inverter, a connection point between the PV converter and the inverter, It is preferable that a bidirectional DC / DC converter provided between the input / output unit is provided.

  In this configuration, the input DC power can be charged in the storage battery, and the power charged in the storage battery can be output from the output unit.

  In the power conditioner according to the present invention, AC power from a power system is input to the first input unit, DC power from a generator is input to the second input unit, and the input monitoring unit is It is preferable to monitor abnormality of the power system.

  In this configuration, the power from the generator can be supplied to the load without an electrical connection with the first input unit during self-sustained operation (for example, during a power failure). Electric power can be supplied from the output unit. In addition, it is possible to prevent power from flowing from the generator to the power system side during a power failure.

  The power conditioner according to the present invention is based on a detection unit that detects at least one of a voltage value and a current value of AC power output from the output unit, and a voltage value or a current value detected by the detection unit, It is preferable to include a control signal output unit that outputs a control signal to an external device to which AC power output from the output unit is supplied.

  In this configuration, for example, when the amount of output power is low, driving of an external device that supplies power can be stopped to reduce power consumption on the load side.

  According to the present invention, only by connecting a load to the output part of the power conditioner, AC power can be supplied to the load from the same output part regardless of whether or not AC power is input from the first input part. .

The figure which shows the power supply system by which the power conditioner which concerns on Embodiment 1 was wired Flow chart showing operation of control unit The figure which shows the power supply system by which the power conditioner which concerns on Embodiment 2 was wired The figure which shows the power supply system by which the power conditioner which concerns on Embodiment 3 was wired The figure which shows the power supply system by which the power conditioner which concerns on Embodiment 4 was wired

(Embodiment 1)
FIG. 1 is a diagram illustrating a power supply system in which the power conditioner 1 according to the first embodiment is wired.

  The power conditioner 1 includes a first input unit IN1, a second input unit IN2, and an output unit OUT. The power system 101 is connected to the first input unit IN1, and AC power is input. The photovoltaic panel 102 is connected to the second input unit IN2, and DC power generated by the photovoltaic panel 102 is input. The output unit OUT outputs AC power. A distribution board 103 is connected to the output unit OUT, and AC power is supplied from the power conditioner 1 to the distribution board 103.

  The photovoltaic panel 102 corresponds to a “generator” according to the present invention. In addition to the photovoltaic panel 102, the generator may be a wind generator or a gas generator. The distribution board 103 includes a main breaker 103A and a plurality of branch breakers 103B connected to the main breaker 103A. The AC power output from the output unit OUT is input to the main breaker 103A and is then supplied to each branch breaker 103B. Each branch breaker 103B is connected to an AC output terminal (AC outlet or the like) (not shown). Loads 111, 112, 113, and 114 are connected to the AC output terminal. Examples of the load include a microwave oven, a washing machine, and an air conditioner.

  The power conditioner 1 includes a switch element S1 provided in a power feeding path (corresponding to a “first path” according to the present invention) from the first input section IN1 to the output section OUT. The switch element S1 corresponds to a “first switch element” according to the present invention. During normal times when there is no abnormality in the power system 101, the switch element S1 is turned on. The AC power input from the first input unit IN1 is supplied from the output unit OUT to the distribution board 103. When the power system 101 is abnormal, the switch element S1 is turned off. Here, the abnormality of the power system 101 is, for example, a power failure, and in the following, the abnormality of the power system 101 is described as a power failure.

  The power conditioner 1 includes a DC / AC inverter 11 provided in a power feeding path (corresponding to a “second path” according to the present invention) from the second input section IN2 to the output section OUT. The DC / AC inverter 11 converts the DC power input from the second input unit IN2 into AC power. The DC / AC inverter 11 and the output unit OUT are always electrically connected. For this reason, the DC power input from the second input unit IN2 is converted into AC power by the DC / AC inverter 11 regardless of whether there is a power failure, and the AC power is supplied from the output unit OUT to the distribution board 103. The

  As described above, in the case of a power failure, the switch element S1 is turned off. For this reason, the electric power generated by the photovoltaic panel 102 can be prevented from flowing into the electric power system 101 at the time of a power failure.

  The power conditioner 1 includes a control unit 12. The control unit 12 includes an output monitoring unit 121, an input monitoring unit 122, a power failure determination unit 123, a switching control unit 124, and a communication unit 125.

  The output monitoring unit 121 monitors the voltage value and current value of AC power output from the output unit OUT. The output monitoring unit 121 corresponds to a “detection unit” according to the present invention. Note that the output monitoring unit 121 may monitor only one of the voltage value and the current value.

  The input monitoring unit 122 monitors the power supply frequency of the AC power that appears at the first input unit. The power failure determination unit 123 determines the presence or absence of a power failure from the monitoring result by the input monitoring unit 122. During normal times when there is no power failure, both the power system 101 and the output from the DC / AC inverter 11 are connected to the first input unit IN1, and the power supply frequency is stable at a predetermined frequency (for example, 60 Hz). When a power failure occurs, only the output from the DC / AC inverter 11 flows into the first input unit IN1. In general, in the power conditioner 1, the power frequency of the AC power output from the DC / AC inverter 11 is swept with a predetermined width in order to prevent isolated operation when a plurality of units are connected. Therefore, the power supply frequency of the AC power appearing at the first input unit IN1 varies depending on whether a power failure occurs or not. Using this, the power failure determination unit 123 determines the presence or absence of a power failure depending on whether or not the power frequency of the AC power appearing at the first input unit IN1 is displaced.

  The switching control unit 124 performs switching control of the switch element S <b> 1 based on the determination result by the power failure determination unit 123. When the power failure determination unit 123 determines that a power failure has not occurred, the switching control unit 124 turns on the switch element S1. As a result, AC power input from the first input unit IN1 and AC power converted from DC power by the DC / AC inverter 11 are supplied from the output unit OUT to the distribution board 103. When the power failure determination unit 123 determines that a power failure has occurred, the switching control unit 124 turns off the switch element S1. Thereby, only AC power converted from DC power by the DC / AC inverter 11 is supplied from the output unit OUT to the distribution board 103. Therefore, AC power is always supplied to the distribution board 103 regardless of whether there is a power failure.

  The communication unit 125 performs data communication with the loads 111 to 114 when the loads 111 to 114 have a communication function. And the communication part 125 outputs the stop signal which instruct | indicates the stop of operation | movement with respect to the loads 111-114, or the drive signal which instruct | indicates restart of the stopped operation | movement. The communication unit 125 corresponds to a “control signal output unit” according to the present invention.

  For example, at the time of a power failure, only the power generated by the photovoltaic panel 102 is output from the output unit OUT after being converted into AC power by the DC / AC inverter 11, so that the output power from the output unit OUT is light The amount of power generated by the power generation panel 102 or the output capacity of the DC / AC inverter 11 is limited. As a result of monitoring by the output monitoring unit 121, when the output voltage value from the output unit OUT decreases beyond a certain threshold, or when the output current value increases beyond a certain threshold, the communication unit 125 A stop signal is output to 111-114. Thereby, the power consumption on the load side at the time of a power failure can be suppressed. Moreover, when it recovers from a power failure (power recovery), the communication part 125 outputs a drive signal to the load 111-114 which stopped operation | movement.

  When the loads 111 to 114 are managed and controlled by one control device (not shown), the communication unit 125 may communicate with the control device. In this case, for example, when the control device manages the power consumption of each of the loads 111 to 114 and receives a stop signal from the communication unit 125, the control device starts from a load with high power consumption or a load that does not hinder the operation. In order, the operation is stopped. Thereby, the power consumption of the loads 111-114 can be suppressed effectively.

  The communication unit 125 may communicate with a server provided by an electric power company and receive information related to power supply from the server. The information related to power supply is, for example, a request to suppress power consumption due to power shortage, a power outage schedule, and the like. And the communication part 125 will output a stop signal with respect to the loads 111-114, if the information regarding electric power supply is received. In the present embodiment, the switch element S1 is illustrated as one switch, but two switches may be connected in series.

  FIG. 2 is a flowchart showing the operation of the control unit 12.

  The controller 12 turns on the switch element S1 (S1). As a result, power from the first input unit IN1 and power from the second input unit IN2 are output from the output unit OUT. Next, the control part 12 determines the presence or absence of a power failure by whether the power supply frequency of the alternating current power which appears in the 1st input part IN1 has displaced (S2).

  When it determines with not having a power failure (S2: NO), the control part 12 performs the process of S2. If it is determined that a power failure has occurred (S2: YES), the control unit 12 turns off the switch element S1 (S3). Thereby, only the electric power input from the second input unit IN2 is output from the output unit OUT. Therefore, even during a power failure, power is supplied from the output unit OUT to the distribution board 103. In addition, since the switch element S1 is off, power does not flow into the power system 101 during a power failure.

  Next, the control unit 12 determines whether or not power has been restored (S4). When power is not restored (S4: NO), the control unit 12 executes the process of S4. When power is restored (S4: YES), the control unit 12 returns to the process of S1 and turns on the switch element S1. Thereby, the electric power input from the first input unit IN1 and the second input unit IN2 is supplied from the output unit OUT to the distribution board 103.

  When it is determined in S2 that there is a power failure, the control unit 12 determines that the load 111 is output when the output voltage value from the output unit OUT decreases beyond a certain threshold value or when the output current value increases beyond a certain threshold value. A stop signal is output to .about.114. Thereby, the power consumption of the load at the time of a power failure can be suppressed. And when it determines with having recovered in S4, the control part 12 outputs a drive signal to the loads 111-114 which stopped operation | movement.

  As described above, in the present embodiment, AC power is always supplied to the distribution board 103 by simply connecting the distribution board 103 to the power conditioner 1 regardless of the presence or absence of a power failure. Therefore, electric power is always supplied to the loads 111 to 114 connected to the distribution board 103. For this reason, since the load is used at the time of a power failure as in the prior art provided with a self-supporting outlet to which power is supplied at the time of a power failure, it is possible to save the trouble of changing the load to the independent power outlet. Moreover, since the switch which switches an electric power feeding path is provided in the power conditioner 1, the wiring between the power conditioner 1 and the distribution board 103 does not become complicated. For this reason, even if it is a wired building, rewiring is not necessary by using the power conditioner 1 according to the present embodiment.

  Moreover, by turning off the switch element S1 at the time of a power failure, it is possible to prevent the power input from the second input unit IN2 from flowing into the power system 101 side. For this reason, the danger at the time of working around the electric power system 101 at the time of a power failure can be avoided.

  In the present embodiment, the power conditioner 1 includes the control unit 12 that communicates with the loads 111 to 114 and the like, but may not include the communication unit 125.

(Embodiment 2)
FIG. 3 is a diagram illustrating a power supply system in which the power conditioner 2 according to the second embodiment is wired.

  The power conditioner 2 includes a switch element S2 provided between the DC / AC inverter 11 and the output unit OUT. The switch element S2 corresponds to a “second switch element” according to the present invention. The switching element S2 is subjected to switching control by the switching control unit 124.

  In addition to the functions described in the first embodiment, the control unit 12 further includes a failure determination unit 126 that detects a failure (for example, a short failure) of the DC / AC inverter 11. The failure detection unit 126 corresponds to an “abnormality detection unit” according to the present invention. The failure detection unit 126 detects a failure of the DC / AC inverter 11 by detecting that an overcurrent has flowed when the semiconductor element inside the DC / AC inverter 11 is turned off, for example.

  The switch element S2 is turned on during normal times. When a failure of the DC / AC inverter 11 is detected, the switch element S2 is turned off. Thereby, it is possible to prevent the DC power input from the second input unit IN2 from being supplied from the output unit OUT to the distribution board 103 without being converted into AC power.

  Note that the failure determination of the DC / AC inverter 11 is executed every predetermined time. In the present embodiment, the switch elements S1 and S2 are illustrated as one switch, but two switches may be connected in series.

  Since the switching control of the switch element S1 in the present embodiment is the same as that in the first embodiment, the description thereof is omitted.

(Embodiment 3)
FIG. 4 is a diagram illustrating a power supply system in which the power conditioner 3 according to the third embodiment is wired.

  The power conditioner 3 includes a switch element S3 provided between the connection point of the switch elements S1 and S2 and the output part OUT. The switch element S3 corresponds to a “third switch element” according to the present invention. The switching element S3 is subjected to switching control by the switching control unit 124. The switch elements S2 and S3 are turned on during normal times. When the DC / AC inverter 11 fails, the switch elements S2 and S3 are turned off.

  Thereby, it is possible to prevent the DC power input from the second input unit IN2 from being supplied from the output unit OUT to the distribution board 103 without being converted into AC power. Also, by providing two switch elements S2 and S3 between the DC / AC inverter 11 and the output unit OUT, one of them becomes a short circuit abnormality (becomes on even though it is off). However, if the other can be normally turned off, the DC power input from the second input unit IN2 can be prevented from being supplied from the output unit OUT to the distribution board 103.

  The switch element S3 is turned on when it is not a power failure, but may be forcibly turned off when it is determined that the DC / AC inverter 11 has failed. Further, whether or not the switch element S2 is not short-circuited abnormally is detected, and if it is not short-circuited abnormally, the switch element S3 may not be turned off. In the present embodiment, each of the switch elements S1 to S3 is shown as one switch, but two switches may be connected in series.

  Since the switching control of the switch element S1 in the present embodiment is the same as that in the first embodiment, the description thereof is omitted.

(Embodiment 4)
FIG. 4 is a diagram illustrating a power supply system in which the power conditioner 4 according to the fourth embodiment is wired.

  The power conditioner 4 includes a PV converter 13 provided between the second input unit IN2 and the DC / AC inverter 11. The PV converter 13 converts the voltage of the DC power input from the second input unit IN2 into a constant output value. The power converted by the PV converter 13 is converted to AC power by the DC / AC inverter 11 and supplied from the output unit OUT to the distribution board 103.

  The power conditioner 4 includes an input / output unit IO, a switch element S4, and a bidirectional DC / DC converter 14. One end of the bidirectional DC / DC converter 14 is connected to the connection between the DC / AC inverter 11 and the PV converter 13, and the other end is connected to the input / output unit IO via the switch element S4.

  A storage battery 104 is connected to the input / output unit IO. The input / output unit IO outputs DC power to the storage battery 104. The output DC power is charged in the storage battery 104. In addition, the input / output unit IO inputs DC power charged in the storage battery 104.

  The bidirectional DC / DC converter 14 boosts or steps down the DC power input from the second input unit IN2, and outputs the boosted or reduced voltage to the input / output unit IO. In addition, the bidirectional DC / DC converter 14 boosts or steps down the DC power input from the input / output unit IO and outputs it to the DC / AC inverter 11. The DC / AC inverter 11 converts the DC power from the bidirectional DC / DC converter 14 into AC power and outputs the AC power to the output unit OUT.

  The switching element S4 is subjected to switching control by the switching control unit 124 (see FIG. 1) of the control unit 12. When the switch element S4 is turned on, power is output to the storage battery 104 or charging power is input from the storage battery 104. For example, when the storage battery 104 is fully charged, the power conditioner 2 may turn off the switch element S4. Further, the power conditioner 2 may turn on the switch element S4 and output the charging power of the storage battery 104 to the distribution board 103 when the power generation by the photovoltaic panel 102 is not sufficient.

  Note that switching control of the switch elements S1, S2, and S3 is the same as in the first to third embodiments, and thus the description thereof is omitted.

  As described above, the power conditioner 4 according to the present embodiment charges the storage battery 104 with the power generated by the photovoltaic panel 102 and outputs the power charged in the storage battery 104 to the distribution board 103. In the present embodiment, as in the first to third embodiments, the electric power charged in the storage battery 104 without the electrical connection to the first input unit IN1 during the self-sustaining operation is supplied from the same output unit OUT to the loads 111 to 114. Therefore, when using the load at the time of a power failure, it is possible to save the trouble of connecting the load to an independent outlet as in the prior art. Moreover, since the switch which switches an electric power feeding path is provided in the power conditioner 4, the wiring between the power conditioner 4 and the distribution board 103 does not become complicated. For this reason, even if it is a wired building, by using the power conditioner 4 according to this embodiment, there is no need for rewiring.

  The configurations of the PV converter 13, the bidirectional DC / DC converter 14, and the switch element S4 described in the present embodiment may be applied to the power conditioners 1 to 3 of the first to third embodiments.

1, 2, 3, 4 ... power conditioner 11 ... DC / AC inverter 12 ... control unit 13 ... PV converter 14 ... DC / DC converter 101 ... power system 102 ... photovoltaic panel 103 ... distribution board 103A ... main breaker 103B ... Branch breaker 104 ... Storage batteries 111, 112, 113, 114 ... Load (external device)
121 ... Output monitoring unit (detection unit)
122 ... Input monitoring unit 123 ... Power failure determination unit 124 ... Switching control unit 125 ... Communication unit 126 ... Failure detection unit (abnormality detection unit)
IN1 ... first input unit IN2 ... second input unit IO ... input / output unit OUT ... output unit S1 ... switch element (first switch element)
S2: Switch element (second switch element)
S3: Switch element (third switch element)
S4: Switch element

Claims (6)

A first input unit for inputting AC power;
A second input unit for inputting DC power;
An output unit for outputting AC power;
An inverter that converts DC power input from the second input unit into AC power;
A first path that electrically connects the first input unit and the output unit;
A second path for electrically connecting the inverter and the output unit;
A first switch element provided in the first path, for electrically connecting or blocking the first path;
An input monitoring unit for monitoring whether AC power is input from the first input unit;
A control unit that turns on the first switch element when AC power is input from the first input unit, and that turns off the first switch element when AC power is not input from the first input unit. When,
Power conditioner with A second switch element that is provided in the second path and electrically connects or disconnects the second path;
An abnormality detection unit for detecting an abnormality of the inverter;
With
The controller is
When the abnormality detection unit detects an abnormality, the second switch element is turned off.
The power conditioner according to claim 1. The first path and the second path are connected to the output unit by connecting one end of the first switch element and the second switch element on the output unit side,
A third switch element provided between a connection point of the first switch element and the second switch element and the output unit;
Further comprising
The controller is
When the abnormality detection unit detects an abnormality, the second switch element and the third switch element are turned off.
The power conditioner according to claim 2. An input / output unit to which the storage battery is connected;
A PV converter provided between the second input unit and the inverter;
A bidirectional DC / DC converter provided between a connection point between the PV converter and the inverter and the input / output unit;
The power conditioner in any one of Claim 1 to 3 provided with these. AC power from the power system is input to the first input unit,
DC power from a generator is input to the second input unit,
The input monitoring unit monitors an abnormality of the power system,
The power conditioner in any one of Claim 1 to 4. A detection unit for detecting at least one of a voltage value and a current value of AC power output from the output unit;
Based on the voltage value or current value detected by the detection unit, a control signal output unit that outputs a control signal to an external device to which AC power output from the output unit is supplied;
The power conditioner in any one of Claim 1 to 5 provided with these.

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