JP5885598B2 - Power control device - Google Patents

Description

  The present invention relates to an inverter that converts DC power supplied from the outside into AC power, and a power load to which AC power is supplied from the power system, and AC power converted by the inverter is connected to the power system. The present invention relates to a power control apparatus including a control unit that performs control so that the inverter is supplied and a disconnect relay for disconnecting the inverter from the power system.

  In recent years, electric vehicles have begun to spread in place of vehicles using internal combustion engines that have a large environmental load due to exhaust gas. In anticipation of further popularization of electric vehicles, attempts have been made to effectively use the electric power stored in the electric vehicles in each home. There, the DC power supplied from the electric vehicle is converted into AC power linked to the power system by the power converter and supplied to the household electric load. Thereby, so-called VtoH (Vehicle to Home) is realized.

  Similarly, a power control device (also referred to as a power conditioner) is used when power generated by a power generation device such as a solar panel or a cogeneration device is supplied to a power load connected to the power system. In this way, the power control device plays an important role in the interconnection with the power system. However, if the power system fails, the power control device continues to operate independently while connected to the power system in order to ensure safety. It is prohibited. On the other hand, when a power failure due to a disaster or the like is assumed, it is preferable that power is supplied to the power load after the connection with the power system is cut off by a breaker so that the power can be backed up.

  For example, in Patent Document 1, when an abnormality occurs in the power system, the power conversion device (power control device) is operated independently, and then the power conversion device is connected to the system when the power system returns to normal. A distributed power system that can be returned to operation is disclosed. Further, Patent Document 2 discloses a technology that enables a self-sustained operation to be started and stopped during a power failure by a power generation device that is linked to the power system.

JP-A-8-196040 JP 2006-254537 A

  However, in the technique disclosed in Patent Document 1, only a part of the plurality of power loads connected to the bus in the distribution board is a target to be backed up by the independent operation. The power conversion device includes a relay that cuts off the power load and other power loads and a part of the bus that is cut off by the relay, and the configuration becomes complicated. Further, based on the voltage and frequency range detected for the power system, the power conversion device is switched between the interconnected operation and the independent operation. Depending on the content of the abnormality in the own system, the power conversion device is operated during the independent operation. There is a problem that it cannot be reliably disconnected from the power system. This may result in a dangerous situation where the inverter voltage is applied to the power system during a power outage, or power that is not connected to the power system flows backward to the power system, causing an abnormality in the power system voltage. As a result, the safety of self-sustained operation may be impaired.

  Moreover, in the technique disclosed in Patent Document 2, when a power failure of the power system is detected and the autonomous operation of the power supply device is started, the generated power generated by the generator is supplied to the outside from the independent output terminal. There has been a problem that generated electric power is not supplied to an electric load (power load) connected to a bus in the switchboard (distribution panel).

  The present invention has been made in view of such circumstances, and an object of the present invention is to execute independent operation only when conditions for allowing independent operation are surely established, and to An object of the present invention is to provide a power control apparatus capable of supplying AC power to a power load connected to the.

The power control device according to the present invention includes: an inverter that converts DC power into AC power; and an AC power that is converted by the inverter is supplied to the power load that is supplied from the power system via a breaker and a current detector. In a power control device including a control unit that controls to be supplied in connection with a system, and a disconnect relay for disconnecting the inverter from the power system, the power control device is connected in parallel to the disconnect relay. cage, a second disconnection relay the breaker is turned off by the on contacts and control voltage applied from the electric power system through the breaker when closed, the disconnecting relays, the control voltage by Yes in the ounce so that, the control unit includes a storage unit which the own device stores whether the predetermined operating state, determine whether the current detector detects the current And a receiving unit that receives an instruction to place the device in the predetermined operating state when the storing unit stores the fact that the storing unit is not in the predetermined operating state. And the determination means determines that the inverter is connected to the power load by the second disconnecting relay and the storage means stores the fact that the predetermined operating state is present. It is characterized by being.

In the present invention, the second disconnection relay connected in parallel to the disconnection relay is configured to be turned off by the control voltage applied from the power system when the breaker is in the closed state, In addition, the disconnection relay and the second disconnection relay are not turned on at the same time. When receiving an instruction to put the device that is not in a predetermined operation state into the predetermined operation state, the second disconnection is performed when the breaker is in an open state and no current flowing between the power system and the device is detected. The inverter is connected to the power load by the relay and the own apparatus is set in a predetermined operation state.
Thus, for example, when an instruction to enter a self-sustained operation state is received when the self-device is in an operation state different from the self-sustained operation, a current inflow from the power system and a power system are detected by detecting no current to the power system. As long as the breaker is in the open state when it is detected that there is no outflow of current to the inverter, the inverter is connected to the power load by the second disconnecting relay and the independent operation is started. In other words, before the start of autonomous operation, it is detected that the breaker must be opened by the user, and in addition, it is detected that no current is transferred to the power system. Sex is secured. In addition, during the self-sustained operation, since the disconnection relay is prohibited from being turned on when the second disconnection relay is turned on, the interconnection operation is performed to link the inverter to the power system using the disconnection relay. In such a case, it is possible to prevent the linked operation from being started by erroneous control during the independent operation.

  When receiving an instruction to enter a stand-alone operation state, for example, if the own device is in another operation state such as a connected operation, the other operation state is terminated, and the breaker is detected to be open. The second disconnect relay is not turned on until the current flowing to the system is no longer detected.

  In the power control apparatus according to the present invention, the control unit includes a unit that receives a predetermined signal when the receiving unit receives the instruction and the determination unit determines NO, and the unit outputs the signal. If accepted, the inverter is connected to the power load.

In the present invention, when receiving an instruction to set the own device in a state of independent operation and detecting that a current flowing between the power system and the power system is not detected, and further when a predetermined signal is received, the inverter To the power load.
Thereby, after detecting that the current flowing between the power system is not detected, for example, when a predetermined time arrives or when a start instruction is given by the user, the actual autonomous operation is started.

  In the power control apparatus according to the present invention, when the control unit stores that the storage unit is in the predetermined operation state and determines that the determination unit has detected, the second disconnection is performed. The inverter is disconnected from the power system by a relay, and information indicating that the predetermined operating state is not established is stored in the storage means.

In the present invention, when the device is in a predetermined operating state and a current flowing between the power system is detected, the inverter is disconnected from the power system by the second disconnect relay. Assume that the device itself is not in a predetermined operating state.
Thus, for example, when the self-device is in a self-sustained operation state, it is self-supporting when it is detected that there is an inflow of current from the power system or an outflow of current to the power system by detecting a current to the power system. Stop operation. That is, when current transfer to the power system is detected, the inverter is surely disconnected from the power system and the independent operation is stopped, so that the safety of the independent operation is ensured. In addition, when the breaker is turned on by the user, the second disconnection relay is inevitably turned off due to its configuration, so that the safety of independent operation is doubled.

  The power control apparatus according to the present invention is characterized in that another breaker is connected in series to the breaker.

  In the present invention, since the other breaker is connected in series to the breaker that cuts off the power load from the power system, the breaker opened by the user before the start of the self-sustaining operation is more reliably performed. It is expected.

  The power control apparatus according to the present invention is characterized in that a relay switch is interposed between the breaker and a power load, and the relay switch is turned on by the control voltage.

In the present invention, the control voltage for turning on the relay switch interposed between the breaker that cuts off the power load from the power system and the power load is the contact that turns on when the breaker is in the closed state and the breaker itself. Applied from the electric power system through the contact of
As a result, if the power system fails after the breaker is turned on, the relay switch is inevitably turned off due to its configuration, and even after the breaker is opened, even if the power system recovers from the power failure Since the switch does not turn on, the inverter is disconnected from the power system, and the safety of the independent operation is ensured. Further, when the breaker is turned on after the independent operation is started with the breaker opened, the inverter is disconnected from the power system by the delay time until the relay switch is turned on and the second disconnecting relay. Therefore, the delay time from when the breaker is turned on until the inverter is disconnected from the power system by the second disconnection relay is reduced.

  In the power control apparatus according to the present invention, a voltage detector including a second relay switch is connected to the power system, and the control unit displays a predetermined display when the voltage detector detects a predetermined voltage. It is characterized by comprising display means for performing

In the present invention, when power recovery is detected by a relay switch that operates when the voltage of the power system becomes higher than the predetermined voltage, a predetermined display is performed on the display means.
Thereby, for example, when the power system recovers from a power failure during the self-sustained operation, the effect of power recovery is displayed.

  In the power control apparatus according to the present invention, the breaker is housed in a distribution board having a lid, the control unit includes a detection unit that detects that the lid is opened, and the storage unit includes The fact that the predetermined operation state is stored and the detection means detects that the inverter is disconnected from the power system by the second disconnect relay and the predetermined operation is stored in the storage means It is characterized by memorizing that it is not in a state.

In the present invention, when it is detected that the device is in a predetermined operation state and the lid of the distribution board is opened, the inverter is disconnected from the power system by the second disconnection relay. Assume that the device itself is not in a predetermined operating state.
Thus, for example, when the self-device is in a self-sustained operation state, the self-sustained operation is stopped when it is detected that the breaker lid is artificially opened, and thus the safety of the self-sustained operation is ensured.

According to the present invention, when receiving an instruction to set the own apparatus that is not in a predetermined operation state to the predetermined operation state, an inflow of current from the electric power system and to the electric power system are detected by detecting no current to the electric power system. When it is detected that there is no current outflow, the inverter is connected to the power load by the second disconnecting relay as long as the breaker is in the open state, and the independent operation is started. In addition, during the self-sustained operation, the second disconnection relay is turned on, so that the disconnection relay is prohibited from being turned on. Therefore, the linked operation due to erroneous control is prevented from being started.
Therefore, it is possible to supply the AC power to the power load connected to the power system before the independent operation by executing the independent operation only when the conditions allowing the independent operation are surely established.

It is a block diagram which shows the example of a connection of the power control apparatus which concerns on Embodiment 1 of this invention. It is a flowchart which shows the process sequence of CPU which starts independent operation. It is a flowchart which shows the process sequence of CPU which stops independent operation. It is a block diagram which shows the example of a connection of the power control apparatus which concerns on Embodiment 2 of this invention. It is a block diagram which shows the example of a connection of the electric power control apparatus which concerns on Embodiment 3 of this invention, and the exterior.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.
(Embodiment 1)
FIG. 1 is a block diagram showing a connection example of the power control apparatus according to Embodiment 1 of the present invention. FIG. 1 is a so-called single line diagram. In the figure, reference numeral 2 denotes a power control device. The power control device 2 includes an inverter 21 that converts DC power supplied from a battery (not shown) of an electric vehicle (EV = Electric Vehicle) 1 through a relay contact 20a into AC power. And a transformer 22 for transforming the single-phase two-wire AC voltage output from the inverter 21 into a single-phase three-wire AC voltage. The inverter 21 may be a bidirectional inverter that can convert AC power supplied via the transformer 22 into DC power and supply the DC power to the electric vehicle 1. The neutral point on the secondary side of the transformer 22 is appropriately connected to the ground potential via the relay contact 23a.

  The AC voltage transformed by the transformer 22 is separated via the relay contact 24a of the disconnection relay 24 or the relay contact 34a of the second disconnection relay 34 connected in parallel to the disconnection relay 24 and the leakage breaker 25. The electric leakage breaker 40 accommodated in the electrical panel 4 is supplied. The earth leakage breakers 25 and 40 are turned on except when an abnormality occurs such as when an earth leakage is detected or an overload is detected. The earth leakage breaker 40 is equipped with a neutral wire phase loss protection, and detects the phase failure of the neutral wire during the self-sustained operation to protect the loads 6a, 6b, 6c from overvoltage. The earth leakage breaker 40 may be omitted. The voltage applied to the wiring portion between the relay contacts 24a, 34a and the earth leakage breaker 25 and the current flowing through the wiring portion are detected by a voltage detector 26 and a current transformer (CT = Current Transformer) 27 each comprising a relay switch, The detection result is given to the control unit 28.

  One end of each of the control coils 24c and 34c that drives the relay contacts 24a and 34a is a contact 35a (a contact), 35b (b contact), a contact 36b (b contact), 36a (a contact), and a contact 37a (a Contacts) and 37b (b contacts) are connected to the control unit 28 in series. One end of each of control coils 20c, 23c, 35c, and 36c for driving the relay contacts 20a and 23a and the contacts 35a (and 35b) and 36a (and 36b) is connected to the control unit 28. The other end (not shown) of each of the control coils 20c, 23c, 35c, 36c is connected to a DC power source of the power control device 2, for example. As is apparent from the figure, when the contact 35a (or contact 36a) is on, the contact 35b (or contact 36b) is off, so that it is prohibited to excite the control coils 24c and 34c simultaneously. It has become.

  One end of a control coil 37c that drives the contacts 37a and 37b is connected to one end of a contact 42a that is turned on when the main breaker 42 is closed. The other end of the contact 42a is connected to the L1 line of the power system 5, for example, via the main breaker 42. The other end (not shown) of the control coil 37c is connected to the L2 line of the power system 5 via the main breaker 42, for example. Therefore, when the main breaker 42 is turned on, the contact 42a is turned on, so that one end and the other end of the control coil 37c are connected to the L2 line and the L1 line of the power system 5, respectively. Thereby, the control coil 37c is excited, the contact 37a is turned on, and the contact 37b is turned off. That is, when the main breaker 42 is turned on (or opened), the excitation of the control coil 34c of the second disconnecting relay 34 (or the control coil 24c of the disconnecting relay 24) is prohibited.

  The control unit 28 also includes an operation / display unit 29 for receiving instructions and various operations by the user through push buttons and / or a touch panel, and a main breaker housed in the distribution board 4 (the breaker described in the claims). ) 42 and a detection terminal of a current transformer (current detector) 43 that detects a current flowing between the power system 5 and a detection terminal of a voltage detector 44 that detects a voltage of the power system 5 are connected to each other. Has been. On the LCD (not shown) of the operation / display unit 29, various kinds of information including an operation state described later are displayed. The voltage detector 44 is connected to a power recovery indicator lamp 45 that is turned on when the power system 5 recovers from a power failure.

  The control unit 28 includes a CPU 281. The CPU 281 includes a ROM that stores information such as programs, a RAM that stores temporarily generated information, and an I / O port that performs various inputs and outputs (all illustrated). Are connected to each other by bus. The CPU 281 executes various processes for the power control apparatus 2 to exhibit its functions in accordance with a control program stored in advance in the ROM. In executing these processes, the CPU 281 fetches the detection results from the voltage detectors 26 and 44 and the current transformers 27 and 43, and controls the control coils 20c, 23c, 24c, 34c, 35c, and 36c at the I / O ports, respectively. To turn on (or off) the relay contacts 20a, 23a, 24a, 34a, 35a (or 35b), 36a (or 36b). The CPU 281 also controls the operation of the inverter 21 (output voltage and / or output current, and conversion direction), and receives instructions and signals corresponding to various operations given from the operation / display unit 29.

  In the above-described configuration, the AC voltage supplied from the power system 5 via the main breaker 42 and / or the AC voltage supplied from the power control device 2 via the earth leakage breaker 40 are respectively branched branch breakers 41a, 41b, 41c. Are supplied to loads (electric power loads described in claims) 6a, 6b, 6c. For example, when only commercial power is supplied to the loads 6a, 6b, and 6c, the main breaker 42 and branch breakers 41a, 41b, and 41c are turned on by the user, and the disconnection relay 24 (the relay contact 24a of the disconnection relay 24a: The same applies hereinafter) and the second disconnection relay 34 is turned off. Details will be described later.

  The control unit 28 stores a state number indicating the operation state of the own device or a flag indicating the state in a RAM (not shown). The operation state defined in the first embodiment includes a state of interconnected operation that operates in conjunction with the power system 5 and a state of independent operation that operates by being disconnected from the power system 5 by the main breaker 42. . When the inverter 21 is a bidirectional inverter and the AC power supplied from the power system 5 can be converted into DC power, the state of the charging operation in which the electric vehicle 1 is charged with the converted DC power is defined. Good. An instruction to change the own apparatus to each operation state is given from the operation / display unit 29 by the user.

  For example, when the CPU 281 accepts an instruction to enter a connected operation state when the main breaker 42 is turned on, the CPU 281 turns on the relay contact 20 a and inputs the electric vehicle to the inverter 21. 1 is connected, and the control coil 35c is further excited to turn on the contact 35a. Since the control coil 36c is not excited, the contact 36b is on. As described above, when the main breaker 42 is turned on, the contact point 37a is turned on. Therefore, when the CPU 281 excites the control coil 24c via the contact points 37a, 36b, 35a, the relay contact point 24a is turned on (ie, The disconnection relay 24 is turned on). Thereby, the output of the inverter 21 is connected to the loads 6a, 6b and 6c.

  Next, the CPU 281 starts up the inverter 21 and controls the inverter 21 to output AC power connected to the power system 5. In this case, the CPU 281 sets the inverter 21 to perform current control so that the output current of the inverter 21 detected by the current transformer 27 has an appropriate magnitude.

  In addition, when a power failure of the power system 5 is detected by a power failure detector (not shown) during the interconnected operation, that is, when a so-called single operation is detected, the CPU 281 performs control executed through the contacts 37a, 36b, and 35a. The excitation of the coil 24c is stopped and the disconnect relay 24 is turned off. Since other specific interconnection operation methods are known, a detailed description thereof will be omitted.

  On the other hand, when the main breaker 42 is opened, the contact point 37b is on because the control coil 37c is not excited as described above. Further, since the control coil 35c excited during the interconnected operation is not excited, the contact 35b is turned on. In this state, the CPU 281 excites the control coil 36c to turn on the contact 36a, and when the control coil 34c is excited through the contacts 37b, 36a, 35b, the relay contact 34a is turned on (that is, the second disconnection). The relay 34 is turned on) and ready to start autonomous operation.

  That is, before starting the independent operation, it is necessary to excite the control coils 36c and 34c with the main breaker 42 being opened. However, when there is only one requirement to be detected by the CPU 281 except for processing for receiving signals corresponding to instructions from the user and various operations when starting independent operation, the contacts 37b, 36a, and 35b are set, for example. The output of the control unit 28 that excites the control coil 34c may be turned on first.

Hereinafter, the independent operation will be described with reference to a flowchart.
FIG. 2 is a flowchart showing a processing procedure of the CPU 281 for starting the independent operation, and FIG. 3 is a flowchart showing a processing procedure of the CPU 281 for stopping the independent operation. The processing of FIG. 2 can accept an operation state change instruction given from the operation / display unit 29 when the state number or the state flag stored in the RAM indicates that the state is not a self-sustaining operation state. Fired when 3 is started when the state number or the flag indicating the state stored in the RAM indicates that it is in a self-sustaining operation state, that is, when it is in a self-sustaining operation state. . The following processing is executed by the CPU 281 according to a control program stored in advance in the above-described ROM.

  When the process of FIG. 2 is started, the CPU 281 determines whether or not there is a change instruction from the operation / display unit 29 (S11), and waits until there is a change instruction (S11: NO). When there is a change instruction (S11: YES), the CPU 281 determines whether or not the change instruction is a change instruction to the state of independent operation (S12). When it is not an instruction to change to a state of independent operation (S12: NO), the CPU 281 executes a change process to another operation state (for example, a state of interconnection operation, charging operation, etc.) (S13) in FIG. The process ends.

  When the change instruction from the operation / display unit 29 is an instruction to change to the independent operation (S12: YES), that is, when the change instruction is received (accepting means described in claims), the CPU 281 causes the current transformer 43 to It is determined whether or not an electric current has been detected (S15: determination means described in claims), and if it is detected (S15: YES), the process of step S15 is repeated. As a result, the CPU 281 waits until the main breaker 42 is opened by the user and no current flows between the main breaker 42 and the power system 5.

  When the current transformer 43 does not detect a current (S15: NO), the CPU 281 determines whether or not a start button (not shown) is pressed by a signal given from the operation / display unit 29 (S17). If not (S17: NO), the process of step S17 is repeated. As a result, the CPU 281 waits until the user makes a clear intention display to start the autonomous operation. In order to continue the determination in step S15 during this standby, the process may be returned to step S15 as indicated by a broken line.

When the start button is pressed (S17: YES), that is, when a signal corresponding to the start button is received (means for receiving a predetermined signal described in claims), the CPU 281 proceeds to a process of starting a self-sustaining operation. Specifically, the CPU 281 first grounds the secondary neutral point of the transformer 22 (S18). Thereby, the balance of the voltage on the secondary side by the three-wire system is prevented from being lost.
Instead of waiting for the start button to be pressed, the autonomous operation may be started when other conditions such as the elapse of a predetermined time, the arrival of a predetermined time, and acquisition of a predetermined signal are satisfied.

  Next, the CPU 281 turns on the relay contact 20a to connect the inverter 21 and the electric vehicle (EV) 1 (S19), and turns on the second disconnecting relay 34 by exciting the control coils 36c and 34c. (S20) The output of the inverter 21 is connected to the loads 6a, 6b, 6c. Further, the CPU 281 activates the inverter 21 (S21) and controls the AC power to be supplied from the inverter 21 to the loads 6a, 6b, and 6c.

In this case, the CPU 281 sets the inverter 21 to perform voltage control so that the output voltage of the inverter 21 detected by the voltage detector 26 becomes a constant AC voltage. After that, the CPU 281 stores a state number or flag indicating that it is in a self-sustaining operation in the RAM (S22), and ends the process of FIG. Before the process of FIG. 2 is terminated, the operation / display unit 29 may display that the independent operation has started.
Note that the order in which the processing from step S18 to S21 is executed is not limited to the order shown in FIG. 2, and may be changed as appropriate so that, for example, the voltage of each part can be raised smoothly to prevent the occurrence of an inrush current. .

Next, the process of FIG. 3 will be described.
When the process of FIG. 3 is activated, the CPU 281 determines whether or not the current transformer 43 has detected a current (S31), and when detected (S31: YES), the CPU 281 will be described later in order to stop the independent operation. The process moves to step S33. For example, the excitation of the control coil 36c may be stopped first at this stage. When the current transformer 43 does not detect a current (S31: NO), the CPU 281 repeats the process of step S31. As a result, the self-sustained operation is continued when the main breaker 42 is opened and the current transformer 43 does not detect a current. When the voltage detector 44 detects a power recovery of the power system 5 when the voltage of the power system 5 becomes equal to or higher than a predetermined voltage during the self-sustained operation, the CPU 281 displays a message indicating the power recovery on the operation / display unit 29. (Display means described in claims: not shown in the flowchart).

When the current transformer 43 detects a current (S31: YES), the CPU 281 proceeds to a process of stopping the independent operation. Specifically, the CPU 281 first stops the inverter 21 (S33), and further stops the excitation of the control coils 36c and 34c to turn off the second disconnecting relay 34 (S34). Disconnect from 5 without fail. The CPU 281 also turns off the relay contact 20a to cut off the connection between the inverter 21 and the electric vehicle (EV) 1 (S35), opens the neutral point on the secondary side of the transformer 22 (S36), and further operates independently. A state number or flag indicating that it is not in storage is stored in the RAM (S37), and the processing of FIG. Before the process of FIG. 3 is terminated, a message indicating that the self-sustaining operation has been stopped may be displayed on the operation / display unit 29.
In addition, the order which performs the process from step S33 to S36 is not limited to the order shown in FIG. 3, The alternating voltage supplied to the distribution board 4 from the power control apparatus 2 via the earth leakage breaker 40 falls the fastest It may be changed as appropriate.

As described above, according to the first embodiment, the second disconnection relay connected in parallel to the disconnection relay is applied from the L1 line and the L3 line of the power system when the main breaker is in the closed state. The circuit configuration is such that it is turned off by the control voltage and the disconnecting relay and the second disconnecting relay are not simultaneously turned on. When an instruction to change the self-device to the state of self-sustained operation is received, the inverter is powered by the second disconnect relay when the breaker is open and no current flowing between the main breaker and the power system is detected. Connect to the load and start independent operation. In other words, before the start of autonomous operation, it is detected that the breaker must be opened by the user, and in addition, it is detected that no current is transferred to the power system. Sex is secured. Moreover, when it is decided to perform the interconnection operation in which the inverter is linked to the power system using the disconnection relay, the interconnection operation is prevented from being started by erroneous control during the independent operation.
Therefore, it is possible to supply the AC power to the power load connected to the power system before the independent operation by executing the independent operation only when the conditions allowing the independent operation are surely established.

Moreover, it waits until a start button is pressed before actually starting independent operation.
Therefore, it is possible to wait for the user to display a clear intention to start the autonomous operation and to start the actual autonomous operation.

Further, when power recovery is detected by a voltage detector comprising a relay switch that operates when the voltage of the power system becomes higher than a predetermined voltage, a predetermined display is performed on the display means.
Therefore, for example, it is possible to display a message indicating that the power system has recovered from a power failure during self-sustained operation and prompt the user to take some measures.

  Furthermore, when the self-device is in a self-sustained operation state and a current flowing between it and the power system is detected, the inverter is disconnected from the power system by the second disconnection relay and the independent operation is stopped. To do. In other words, when current transfer to the power system is detected, the inverter is reliably disconnected from the power system and the independent operation is stopped. In addition, when the main breaker is turned on by the user, the second disconnection relay is inevitably turned off due to its configuration, so that it is possible to ensure the safety of independent operation.

(Embodiment 2)
The first embodiment is a mode in which one breaker that can be manually opened and closed (only the main breaker 42) is provided between the power system 5 and the disconnection relay 24, except for the leakage breakers 25 and 40. On the other hand, Embodiment 2 is a form provided with two such breakers.
FIG. 4 is a block diagram showing a connection example of the power control apparatus 2 according to Embodiment 2 of the present invention.

  In FIG. 4, a second main breaker (another breaker described in claims) 46 is connected in series with the main breaker 42 between the main breaker 42 and the earth leakage breaker 40. Both ends of a contact 46 a that outputs a contact signal indicating an open / closed state of the second main breaker 46 are connected to the control unit 28. The controller 28 is also connected with a contact 47 that outputs a contact signal indicating that a lid (not shown) of the distribution board 4 has been opened. Other configurations are the same as those in FIG. 1 in the first embodiment.

The second main breaker 46 is for making the user more surely cut off from the power system 5 when starting the self-sustaining operation. For example, when the user causes the power control apparatus 2 to start a self-sustained operation, it is obliged to open the second main breaker 46 in addition to the main breaker 42.
Therefore, since it is expected that the breaker opened by the user before the start of the self-sustained operation is more reliably performed, the safety of the self-sustained operation can be improved.

Further, when the contact 46a is provided and both ends of the contact 46a are connected to the control unit 28 as in the second embodiment, the CPU 281 takes in the contact signal output from the contact 46a, and starts and stops the independent operation. It can be used for the determination at the time. For example, a determination (S16) as to whether or not the second main breaker 46 is opened is added during the steps S15 and S17 in FIG. 2 described above, and the opening of the second main breaker 46 is not detected ( By returning the process to step S15 to S16: NO), the start of the independent operation is reserved. If the current is not detected in step S31 of FIG. 3 (S31: NO), a determination is made as to whether or not the second main breaker 46 is open (S32), and the second main breaker 46 is added. When the opening of the vehicle is not detected (S32: NO), the process is shifted to step S33, whereby the autonomous operation is stopped.
Therefore, according to the second embodiment, it is possible to further improve the safety of the independent operation.

The contact 47 is used to detect in advance that an erroneous operation by the user may occur. Specifically, when the current is not detected in step S31 of FIG. 3 described above (S31: NO), the CPU 281 takes in the contact signal output from the contact 47, and the lid is opened by the contact signal. Is detected (detection means described in claims). When it is detected that the lid has been opened (or when it has not been detected that the lid has been opened), the CPU 281 moves the process to step S33 (or S31). Thereby, it is detected that the lid is artificially opened, and the independent operation is stopped.
Therefore, according to the second embodiment, it is possible to ensure the safety of independent operation.

  In addition, the same code | symbol is attached | subjected to the location corresponding to Embodiment 1, and the description is abbreviate | omitted.

(Embodiment 3)
In the first embodiment, the main breaker 42 and the loads 6a, 6b, and 6c are connected via the branch breakers 41a, 41b, and 41c, while the third embodiment is different from the main breaker 42 and the load. In this embodiment, a relay switch (electromagnetic contactor) 48 is interposed between 6a, 6b and 6c.
FIG. 5 is a block diagram showing an example of connection between the power control apparatus 2 according to Embodiment 3 of the present invention and the outside. 1 and 4 are represented by a single line diagram, whereas FIG. 5 is represented by a double line diagram. 1 and 4, the branch breakers 41a, 41b, and 41c are not shown in FIG.

  In FIG. 5, each of the current transformers 43 a and 43 b detects the current flowing through the main breaker 42 and the L1 line and L2 line of the power system 5 and supplies the detected current to the control unit 28. N is a neutral wire. The voltage detector 44 detects the voltage between the L1 line and the L2 line and supplies it to the control unit 28. The main breaker 42 has a contact 42a that is turned on when the main breaker 42 is closed.

  A relay contact of a relay switch 48 is interposed between the main breaker 42, the loads 6a, 6b, 6c and the earth leakage breaker 40. The relay contact is turned on when the control coil 48c is excited. It has become. One end of the contact 42a is connected to the L1 line between the main breaker 42 and the relay switch 48, and the other end is connected to one end of the control coil 48c. The other end of the control coil 48c is connected to the L2 line between the main breaker 42 and the relay switch 48.

  In the configuration of FIG. 5, the main circuit breaker 42 is opened and opened during the self-sustaining operation, and the contact 42 a is turned off. Therefore, the main circuit breaker is connected to the one end of the control coil 48 c from the L1 line of the power system 5. 42 and the control voltage to be applied through the contact 42a is not applied. Further, the control voltage to be applied from the L2 line of the power system 5 via the main breaker 42 is not applied to the other end of the control coil 48c. As a result, the relay switch 48 is turned off, and the main breaker 42 is disconnected from the loads 6a, 6b, 6c and the earth leakage breaker 40.

  Next, when the main breaker 42 is accidentally turned on during the autonomous operation, the contact 42a is turned on, the control voltage is applied from the L1 line to one end of the control coil 48c, and the power system 5 is connected to the other end of the control coil 48c. Since the control voltage is applied from the L2 line via the main breaker 42, the relay switch 48 is turned on, and the main breaker 42 is connected to the loads 6a, 6b, 6c and the earth leakage breaker 40. However, the time from when the main breaker 42 is turned on until the relay switch 48 is turned on, the time until the contact 42a is turned on, and the time until the control coil 48c of the relay switch 48 is excited and the relay contact is turned on. Therefore, the delay time until the inverter 21 is disconnected from the electric power system 5 by the second disconnection relay 34 is reduced.

  In addition, the same code | symbol is attached | subjected to the location corresponding to Embodiment 1, and the description is abbreviate | omitted.

As described above, according to the third embodiment, the control voltage for turning on the relay switch interposed between the main breaker that cuts off the load (electric power load) from the power system and the load and the earth leakage breaker is the main voltage. It is applied from the electric power system through a contact point that is turned on when the breaker is in a closed state and a contact point of the main breaker itself.
Therefore, if the power system fails after the main breaker is turned on, the relay switch is turned off. After the main breaker is opened, the relay switch is turned on even if the power system is restored from the power failure. Therefore, the inverter is disconnected from the power system, and it is possible to ensure the safety of the independent operation.
Furthermore, when the breaker is turned on after the autonomous operation is started with the main breaker opened, the relay is controlled by the delay time of the contact that is turned on when the main breaker is closed and the control coil of the relay switch. Since there is an overlap between the time obtained by adding the delay time until the contact is turned on and the delay time until the inverter is disconnected from the power system by the second disconnection relay, the inverter is connected by the second disconnection relay. It becomes possible to reduce the delay time until disconnection from the power system.

  In the third embodiment, the case where the main breaker 42 and the relay switch 48 are connected in series has been described. However, as shown in the second embodiment, the main breaker 42 has a second main trunk. The breaker 46 may be connected in series, and the relay switch 48 may be connected in series. In this case, a contact that is turned on when the second main breaker 46 is closed (a contact different from the contact 46a of the second embodiment) is prepared, and this contact and the above-described contact 42a are connected in series. As a result, the relay switch 48 is turned on only when both the main breaker 42 and the second main breaker 46 are turned on, so that the safety of the independent operation is improved.

  The embodiment disclosed this time is to be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Electric vehicle 2 Electric power control apparatus 21 Inverter 24 Disconnecting relay 28 Control part 281 CPU
29 Operation / Display Unit 34 Second Disconnect Relay 4 Distribution Board 41a, 41b, 41c Branch Breaker 42 Master Breaker 43 Current Transformer 46 Second Master Breaker 48 Relay Switch 5 Power System 6a, 6b, 6c Load

Claims (7)

AC power converted by the inverter is supplied to an inverter that converts DC power into AC power and a power load that is supplied with power from the power system via a breaker and a current detector. In a power control apparatus comprising a control unit for controlling the inverter and a disconnect relay for disconnecting the inverter from the power system,
A parallel connection to the disconnection relay, a contact point that is turned on when the breaker is in a closed state, and a second disconnection relay that is turned off by a control voltage applied from the power system via the breaker,
The disconnection relays is Yes in the ounce so that by the control voltage,
The controller is
Storage means for storing whether or not the own device is in a predetermined operation state;
Determining means for determining whether the current detector has detected a current;
Receiving means for accepting an instruction to place the device in the predetermined operation state when the storage unit stores that the predetermined operation state is not established;
When the accepting means accepts the instruction and the judging means judges NO, the inverter is connected to the power load by the second disconnecting relay and the storage means is in the predetermined operating state. An electric power control device characterized by storing the above. The controller is
And a means for accepting a predetermined signal when the accepting means accepts the instruction and the judging means judges no,
The power control apparatus according to claim 1, wherein when the means receives the signal, the inverter is connected to the power load.   The control unit stores that the storage unit is in the predetermined operating state, and when the determination unit determines that the detection unit has detected, the second disconnecting relay causes the inverter to be disconnected from the power system. The power control apparatus according to claim 1 or 2, wherein the power control apparatus is configured to disconnect and store in the storage means that the predetermined operation state is not established.   4. The power control device according to claim 1, wherein another breaker is connected in series to the breaker. 5. A relay switch is interposed between the breaker and the power load,
The power control apparatus according to claim 1, wherein the relay switch is turned on by the control voltage. A voltage detector comprising a second relay switch is connected to the power system;
The power control apparatus according to any one of claims 1 to 5, wherein the control unit includes a display unit that performs a predetermined display when the voltage detector detects a predetermined voltage. The breaker is housed in a distribution board having a lid,
The controller is
Having detection means for detecting that the lid is opened;
When the storage means stores the predetermined operating state and the detection means detects, the inverter is disconnected from the power system by the second disconnect relay and is stored in the storage means. The power control apparatus according to any one of claims 1 to 6, wherein information indicating that the predetermined operation state is not established is stored.

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