JP5429050B2 - Power converter - Google Patents

Description

  The present invention relates to a power converter for supplying power to a commercial power supply system by performing at least voltage conversion and DC / AC conversion on power generation means and charging a storage battery with the power generation means and the commercial power supply system. Therefore, it is effective in a power conversion device having a power storage function using a solar battery and a storage battery.

  Conventionally, the structure of the power converter device which used the solar cell and storage battery of patent document 1 together is known. And this type of power conversion has the following types.

1. 1. Power conversion from solar cell to commercial power system 2. Power conversion from solar cells to storage batteries Power conversion from a commercial power supply system to a storage battery When performing at least three types of power conversion as described above, it is necessary that the voltages of the respective parts are different and that AC / DC conversion be performed.

  Here, the power conversion device described in Patent Document 1 requires a step-up chopper for a solar cell, a step-up chopper for a storage battery, and a DC / AC conversion circuit (inverter), and in particular, two step-up choppers are necessary. ing.

In general, the voltage of each part is as follows.
・ Solar cell voltage DC50V ~ 380V
・ Storage battery voltage DC200V ~ 350V
・ System voltage AC200V or AC100V
Patent Document 2 is a power conversion device for storing the power of a solar battery in a storage battery. However, when the voltage of the solar battery is lower than the voltage of the storage battery, the voltage of the solar battery is increased. When it is higher, the voltage is stepped down.

JP 2002-171694 A JP 2000-287382 A

  In the case of using the conventional technology as described above, two choppers are required corresponding to a plurality of voltage ranges, and in order to control energization to the step-up or step-down reactor (coil) and the reactor for each of the two choppers. Switch means are required. This increases the number of circuit components and increases the manufacturing cost.

  That is, in the prior art, since there is a step-up chopper for solar cells and a step-up chopper for storage batteries, two chopper reactors are necessary and the cost becomes high. Therefore, a configuration that can be reduced in cost and reduced in size is desired.

  The present invention has been made paying attention to such problems existing in the conventional technology, and an object of the present invention is to provide a power conversion device that can reduce the number of parts and further reduce costs. .

  Descriptions of patent documents listed as prior art can be introduced or incorporated by reference as explanations of technical elements described in this specification.

In order to achieve the above object, the present invention employs the following technical means. That is, according to the first aspect of the present invention, in an apparatus for supplying the generated power of the power generation means to the commercial power supply system by performing at least voltage conversion and DC / AC conversion, and charging the storage battery in the power generation means and the commercial power supply system, Voltage converter circuit comprising a reactor in which current from the means flows from the primary side to the secondary side, and an intermittent switch means for controlling voltage supply by controlling the energization of the reactor, and DC-AC conversion for the output of the voltage conversion circuit DC-AC conversion circuit for outputting the commercial power system performs, and the current flowing through the reactor in the voltage conversion circuit is provided with a circuit switching switch means for selectively directing to the storage battery side and the commercial power supply system side, batteries Are connected to the primary side and the secondary side of the reactor via the circuit changeover switch means, and at least the circuit changeover switch connected to the primary side of the reactor. Through the pitch means, to supply power of the battery to the commercial power system or consumer electronics, characterized in that the storage battery from the commercial power supply is charged through the connected circuit switching switch means on the secondary side of the reactor .

According to the present invention, a voltage conversion circuit including a reactor through which current from the power generation means flows, an intermittent switch means for controlling voltage supply to the reactor to perform voltage conversion, and current flowing through the reactor in the voltage conversion circuit Since the circuit changeover switch means that leads to the storage battery side and the commercial power supply system side is provided, a power conversion device that can perform power conversion at least for the storage battery and the commercial power supply system by using the reactor that is a component of the voltage conversion circuit in common Can be provided. Moreover, since at least the reactor is commonly used, the circuit configuration can be simplified. Further, the primary side and the secondary side of the reactor are connected to each other via a circuit changeover switch means, and at least the power of the storage battery is supplied to the commercial power system or the home appliance via the circuit changeover switch means connected to the primary side of the reactor. The storage battery can be charged with the electric power of the commercial power supply system via the circuit changeover switch means supplied to the product and connected to the secondary side of the reactor.

In the second aspect of the invention, in the apparatus for supplying the generated power of the power generation means to the commercial power supply system by performing at least voltage conversion and DC / AC conversion, and charging the storage battery in the power generation means and the commercial power supply system, DC converter for the output of the voltage conversion circuit and the voltage conversion circuit having the intermittent switch means for controlling the voltage of the reactor through which the current flows from the primary side to the secondary side and controlling the energization of the reactor. A relay provided separately from the intermittent switch means for selectively guiding the current flowing through the reactor in the DC / AC converter circuit and the voltage converter circuit to the commercial power system to the storage battery side and the commercial power system side A circuit changeover switch means including a magnet switch is provided,
The intermittent switch means is composed of switch elements provided on the primary side and the secondary side of the reactor, and the DC / AC conversion circuit performs DC / AC conversion on the output of the voltage conversion circuit supplied via the reactor, The circuit change-over switch means is characterized in that the current flowing through the reactor in the voltage conversion circuit and one of the switching elements is switched between the storage battery side and the commercial power supply system side .

According to the present invention, a voltage conversion circuit including a reactor through which current from the power generation means flows and an intermittent switch means for controlling voltage supply to the reactor to perform voltage conversion, and current flowing through the reactor in the voltage conversion circuit Since the circuit changeover switch means for guiding the battery to the storage battery side and the commercial power supply system side is provided, the power conversion device can perform power conversion for at least the storage battery and the commercial power supply system by using the reactor as a component of the voltage conversion circuit in common Can be provided. Moreover, since at least the reactor is commonly used, the circuit configuration can be simplified. Furthermore, voltage conversion is provided since circuit switching switch means including a relay or magnet switch provided separately from the intermittent switch means for guiding the current flowing through the reactor and one of the switch elements to the storage battery side and the commercial power supply system side is provided. It is possible to provide a power conversion device that can perform power conversion for at least a storage battery and a commercial power supply system by commonly using a reactor and a switch element that are circuit components, and at least using a reactor and a switch element in common. Therefore , simplification of the circuit configuration can be achieved .

The invention according to claim 3 is characterized in that the circuit change-over switch means selects a switch element to be used .

According to the present invention, by selecting the switch element used by the circuit changeover switch means, the voltage conversion circuit is configured with a single reactor, and various types of power conversion are possible.

It is an electric circuit diagram of the power converter device in 1st Embodiment of this invention. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of performing power conversion from a solar cell to a commercial power system. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of performing power conversion from a solar cell to a storage battery. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of performing the power conversion from a storage battery to a commercial power system. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of the electric power transmission from a commercial power system to a storage battery. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of performing power conversion from a fuel cell to a commercial power system. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device when performing the power conversion from a fuel cell to a storage battery. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of performing power conversion from a wind power generator to a commercial power system. In the said embodiment, it is an electric circuit diagram which shows the action | operation of the power converter device in the case of performing the power conversion from a wind power generator to a storage battery. In the said embodiment, it is an electric circuit diagram of the direct current alternating current conversion circuit which converts single phase alternating current into direct current, or reversely converts it. In the said embodiment, it is an electrical circuit diagram of the alternating current direct current | flow conversion circuit which converts three-phase alternating current into direct current | flow. It is an electric circuit diagram of the power converter device especially for photovoltaic power generation used as the power converter device in 2nd Embodiment of this invention. In 2nd Embodiment, it is an electric circuit diagram of the power converter device in the case of selling the electric power of a solar cell to a commercial power system, or consuming with household appliances, such as a household refrigerator. In 2nd Embodiment, it is an electric circuit diagram of the power converter device for solar power generation in the case of charging a storage battery with the electric power of a solar cell. In 2nd Embodiment, it is an electric circuit diagram of the power converter device in the case of selling the electric power of a storage battery to a commercial power system.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration.

  Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also a combination of the embodiments even if they are not clearly shown unless there is a problem with the combination. It is also possible.

(First embodiment)
Hereinafter, the first embodiment of the present invention will be specifically described in detail with reference to FIGS. 1 to 11. FIG. 1 is an electric circuit diagram of a power conversion device 100 according to the first embodiment of the present invention. In FIG. 1, in the first embodiment, a solar cell 1, a fuel cell 3, and a wind power generator 4 are used as power generation means.

  The filters 5 to 8 connected to the power generation means and the storage battery 2 are configured by capacitors, resistors, and the like, and reduce the ripple component of the generated voltage or charging voltage.

  The filter 11 connected to the DC / AC converter (inverter) 10 reduces the ripple component of the waveform converted to AC by the PWM (pulse width modulation) circuit in the DC / AC converter 10. Reference numeral 9 denotes an AC / DC conversion circuit that converts the three-phase AC output of the wind turbine generator 4 into DC.

  As the transistors Tr1, Tr2, and Tr3 constituting the intermittent switch means, switch elements with low loss at the time of switching such as IGBT, super junction MOS (SJ-MOS), SiC power transistor, etc. can be used.

  D1 and D4 are diodes. Further, flywheel diodes D2 and D3 are provided in parallel with the intermittent switch means Tr2 and Tr3. C1, C2, C3, C4, and C5 are capacitors.

  The reactor L1 is energized by the transistors Tr1, Tr2, and Tr3 constituting the intermittent switch means, and generates a high induced electromotive force when the energization current is interrupted. Also, at the time of step-down, it has a role of setting a charging time constant for the capacitor C5 at the subsequent stage.

  That is, when the reactor L1 is energized, the electromagnetic energy accumulated in the reactor L1 can be adjusted by the switch means including the transistors Tr1, Tr2, and Tr3 to obtain a voltage from a high voltage to a low voltage. Step-down is possible. The step-up / step-down circuit itself forming this type of voltage conversion circuit 101 is well known.

  Provided is a power conversion device capable of performing various types of power conversion by switching and selecting components of the voltage conversion circuit 101 and commonly using the transistors L1, Tr2, and Tr3 that constitute the intermittent switch means with the reactor L1. .

  For this purpose, in the first embodiment, by providing circuit changeover switch means comprising contact points SW1, SW2, SW3, SW4, and SW5 of the magnet switch, transistors Tr1, Tr2 that constitute on / off switch means to be used, and Tr3 is selected. Thereby, the voltage conversion circuit 101 is comprised by the single reactor L1, and the above-mentioned various power conversion is enabled.

  The DC / AC converter circuit 10 has an operation as an inverter that converts DC to a predetermined voltage of AC and a rectification and voltage adjustment function that converts AC to a predetermined voltage of DC, and has a PWM (pulse width modulation) circuit therein. It is a known built-in one.

  As described above, SW1, SW2, SW3, SW4, and SW5 are contact points of a magnet switch (electromagnetic switch), and the contact point is driven by electromagnetic force when the internal coil is energized to turn on or off the circuit. I do. It is also possible to use a non-contact power relay by making these contacts non-contact. In practice, a circuit breaker, a meter for selling power, a power meter, a CT (current transformer), and the like for preventing a short circuit are further provided but omitted.

  As described above, at least solar cell 1, storage battery 2, and commercial power supply system 15 are included. Further, in the case of the first embodiment, the fuel cell 3 and the wind power generator 4 are provided. Moreover, it has the direct current alternating current conversion circuit 10 which converts the output of the voltage conversion circuit 101 into the alternating current of the commercial power supply system 15. Conversely, the DC / AC conversion circuit 10 also has a function of converting AC power to DC power and charging the storage battery 2.

  Further, the energization to the reactor L1 in the voltage conversion circuit 101 and the high voltage induced state from the reactor L1 are controlled by turning on and off the transistors Tr1, Tr2, and Tr3 that constitute the intermittent switch means, so that an arbitrary size is achieved. The voltage conversion is performed. Further, by switching the contacts SW1 to SW5 constituting the circuit changeover switch means, it is possible to perform power conversion of the plurality of power generation means and the storage batteries 1, 2, 3, 4 with a single reactor L1.

  The effective value of the sinusoidal alternating current is equal to 0.707 times the maximum value. In FIG. 1, when the voltage of the commercial power supply system 15 is AC 200 V (effective value of AC 200 volts), 200 ÷ 0.707 = 283, and the peak-to-peak voltage (maximum value) is about 280 V.

  Therefore, in order to convert direct current into alternating current by the direct current alternating current conversion circuit (inverter) 10 and supply electric power with a voltage of AC 200 V (effective value of alternating current 200 volts) to the commercial power supply system 15, the direct current alternating current conversion circuit 10 It is necessary to apply a high voltage of 280 volts or more to the input stage voltage Va.

  The voltage at the input stage of the DC / AC converter circuit 10 will be referred to as Va voltage in the following description. In this embodiment, the Va voltage is set to DC 350 V (DC 350 volts) to DC 400 V.

  When the maximum power is obtained from the power generation means such as the solar cell 1, the wind power generator 4, and the fuel cell 3, the output voltages of these power generation means change. For example, when the power generation means is the solar cell 1, when the maximum power is obtained from the solar cell 1, the output voltage of the solar cell 1 changes in the range of DC50V to DC380V. When the power generation means is the fuel cell 3, when the maximum power is obtained from the fuel cell 3, the output voltage of the fuel cell 3 ranges from DC20V to DC200V depending on the type.

  When the power generation means is the wind power generator 4 and the generator in the wind power generator 4 is a three-phase AC generator, the output of the three-phase AC generator is converted by the AC / DC converter circuit 9 as shown in FIG. The output voltage of the AC / DC conversion circuit 9 changes within the range of DC50V to DC380V. The voltage of the storage battery 2 is changed within the range of DC200V to DC350V depending on the state of SOC (remaining capacity).

  Further, description will be made assuming that the voltage of the commercial power supply system 15 is a single-phase AC 200V. Note that the voltage of the commercial power supply system may be AC100V, and it is also possible to use three-phase alternating current or single-phase three-wire wiring, but here, single-phase two-wire The explanation will be made assuming that AC200V is supplied to the house.

In consideration of such voltage fluctuations of the power generation means 1, 3, and 4, and under the above-mentioned restricted Va voltage, the circuit changeover switch means SW 1 to SW 5, the voltage conversion circuit 101, and the DC / AC conversion circuit It is necessary to perform power conversion while adjusting voltage by controlling 10. Hereinafter, this will be described separately for each case.
(1) Case of Power Conversion from Solar Cell to System FIG. 2 is an electric circuit diagram showing the operation of the power conversion apparatus 100 for photovoltaic power generation in the case of power conversion from the solar cell 1 to the system 15 in FIG. is there.

  In the case of power conversion from the solar cell 1 to the system 15, the normally open contacts SW1, SWa, and SWb of the magnet switch constituting the circuit changeover switch means are turned ON as shown in FIG. An excitation (energization) signal of a coil (not shown) in the magnet switch is output from an electronic control unit (ECU) constituting switching control means (not shown).

  Further, the intermittent switch means Tr1 composed of a power transistor (hereinafter simply referred to as a transistor) is always turned on. When the voltage of the solar cell 1 is lower than the Va voltage, it is necessary to boost the voltage. Therefore, the step-up function of the voltage conversion circuit 101 is exhibited by the intermittent switch means Tr3, the diode D2, and the reactor L1.

  That is, the transistors Tr1 and Tr3 are turned on to pass a current through the reactor L1, and then the transistor Tr3 is turned off to charge the capacitor C5 with the induced electromotive force of the reactor L1 through the diode D2. This is repeated at high speed, and the boosted voltage is supplied to the DC / AC converter circuit 10. At this time, if the transistor Tr2 parallel to the diode D2 is turned on in conjunction with the turning off of the transistor Tr3, the loss in the diode D2 can be reduced.

  The voltage is increased until the voltage of the solar cell 1 becomes equal to or higher than the Va voltage. After boosting, the direct current to alternating current circuit 10 converts the direct current into alternating current and outputs it to the commercial power system 15.

When the voltage of the solar cell 1 is equal to or higher than the Va voltage, the voltage, frequency, and phase are set so that the system voltage is AC 200 V by a PWM (pulse width modulation) circuit in the DC / AC converter circuit 10 (inverter). The power is supplied to the grid 15 by adjusting.
(2) Case of Power Conversion from Solar Battery to Storage Battery FIG. 3 is an electric circuit diagram showing the operation of the power conversion device 100 in the case of power conversion from the solar battery 1 to the storage battery 2 in FIG. In the case of power conversion from the solar cell 1 to the storage battery 2, the normally open contacts SW1 and SW3 of the magnet switch are turned on.

  When the voltage of the solar cell 1 is higher than the voltage of the storage battery 2, the step-down function of the voltage conversion circuit 101 is exhibited by the transistor Tr 1, the diodes D 1 and D 4, the reactor L 1, and the capacitor C 2.

  That is, the transistor Tr1 serving as the intermittent switch means is used as a chopper, and only necessary power is supplied to the reactor L1 and the capacitor C2 that form the LC filter in the subsequent stage to be smoothed and applied to the storage battery 2 as a voltage stepped down to a predetermined voltage. ing.

When the voltage of the solar cell 1 is lower than the voltage of the storage battery 2, the transistor Tr1 serving as the intermittent switch means is always turned on, and the transistor Tr3, the diodes D1 and D4, and the reactor L1 exhibit a boosting function. Is boosted.
(3) Case of Power Conversion from Storage Battery to Commercial Power Supply System FIG. 4 is an electric circuit diagram showing the operation of the power conversion device 100 in the case of power conversion from the storage battery 2 to the commercial power supply system 15 in FIG. In the case of power conversion from the storage battery 2 to the grid 15, an electronic control unit (ECU) (not shown) turns on the normally open contacts SW2, SWa, and SWb.

When the voltage of the storage battery 2 is lower than the Va voltage, it is necessary to boost the voltage. Thus, the transistor Tr3, the diode D2, and the reactor L1 cause the voltage conversion circuit 101 to perform a boosting function, thereby boosting the voltage of the storage battery 2. That is, the high voltage of the reactor L1 after turning off the transistor Tr3 is applied to the capacitor C5 via the diode D2 (or the transistor Tr2 turned on).
(4) In the case of power transmission from the commercial power supply system to the storage battery FIG. 5 is an electric circuit diagram showing the operation of the power conversion device 100 in the case of power transmission from the commercial power supply system 15 to the storage battery 2 in FIG. In the case of power transmission from the commercial power supply system 15 to the storage battery 2, the electronic control unit (ECU) turns on the normally open contacts SW2, SWa, and SWb.

When the Va voltage is higher than the voltage of the storage battery 2, it is necessary to step down. In this case, after conversion from AC to DC by the DC / AC conversion circuit 10, the transistor Tr 2, the diode D 3, and the reactor L 1 exhibit a step-down function, step down the Va voltage, and store the battery at the step-down voltage. 2 is charged.
(5) When performing power conversion from the fuel cell to the commercial power supply system FIG. 6 is an electric circuit showing the operation of the power conversion device 100 when performing power conversion from the fuel cell 3 to the commercial power supply system 15 in FIG. FIG. When power is converted from the fuel cell 3 to the commercial power supply system 15, the normally open contacts SW4, SWa, SWb are turned on.

Since the voltage of the fuel cell 3 is lower than the Va voltage, it is necessary to boost the voltage. The transistor Tr3, the diode D2, and the reactor L1 exhibit the boost function of the voltage conversion circuit 101 to boost the voltage of the fuel cell 3. After boosting, the direct current to alternating current conversion circuit 10 converts the direct current to alternating current and supplies it to the commercial power supply system 15.
(6) Case of Converting Power from Fuel Cell to Storage Battery FIG. 7 is an electric circuit diagram showing the operation of the power conversion device 100 when converting power from the fuel cell 3 to the storage battery 2 in FIG. When power is converted from the fuel cell 3 to the storage battery 2, the normally open contacts SW3 and SW4 are turned on.

Since the voltage of the fuel cell 3 is lower than the voltage of the storage battery 2, the transistor Tr 3, the diode D 4, and the reactor L 1 cause the voltage conversion circuit 101 to perform a boosting function, boost the voltage of the fuel cell 3 and charge the storage battery 2.
(7) Case of Converting Power from Wind Power Generation to System FIG. 8 is an electric circuit diagram showing the operation of the power conversion device 100 in the case of converting power from the wind power generation device 4 to the commercial power system 15 in FIG. . When power conversion from the wind power generator 4 to the commercial power supply system 15 is performed, the normally open contacts SW5, SWa, and SWb are turned on.

  The DC voltage after the three-phase AC output of the wind power generator 4 is converted by the AC / DC converter circuit 9 through the filter 8 is lower than the Va voltage, so it needs to be boosted. Therefore, the boosting function of the voltage conversion circuit 101 is exhibited by the transistor Tr3, the diode D2, and the reactor L1.

The three-phase AC output from the wind power generator 4 is converted from AC to DC by the AC / DC conversion circuit 9, and then the DC output voltage is boosted and further converted from DC to AC by the DC / AC conversion circuit 10. 15 is output.
(8) When Converting Power from Wind Power Generation to Storage Battery FIG. 9 is an electric circuit diagram showing the operation of the power conversion device 100 when converting power from the wind power generation device 4 to the storage battery 2 in FIG. When power conversion from the wind power generator 4 to the storage battery 2 is performed, the normally open contacts SW3 and SW5 are turned on.

  Since the output voltage after AC / DC conversion from the wind power generator 4 by the AC / DC conversion circuit 9 is lower than the voltage of the storage battery 2, the transistor Tr 3, the diode D 4, and the reactor L 1 exhibit a boosting function. Thus, the voltage after the AC output of the wind power generator 4 is converted from AC to DC by the AC / DC conversion circuit 9 is boosted, and the storage battery 2 is charged.

  Next, FIG. 10 is a schematic circuit diagram of a DC / AC conversion circuit 10 that converts single-phase AC to DC or reversely converts it. The DC / AC converter circuit 10 forms a bridge with four power transistors. The diode in parallel with the power transistor is a flywheel diode. FIG. 11 is a schematic diagram of an AC / DC conversion circuit 9 that converts three-phase AC to DC. This AC / DC converter circuit 9 forms a bridge for full-wave rectification with six diodes.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. Features different from the above-described embodiment will be described. The second embodiment shows a case where the magnet switch constituting the circuit changeover switch means comprises a changeover switch in which the connection piece is switched to the right and left or upper and lower normally open contacts and normally closed contacts of the common contact.

  FIG. 12 is an electric circuit diagram of the power conversion device for solar power generation, which constitutes the power conversion device 100 according to the second embodiment of the present invention. In FIG. 12, the solar cell 1 is connected to coils 5a and 5b that form a noise-cut filter.

  After the output of the solar cell 1 passes through the coils 5a and 5b, the direct current which forms an inverter through the changeover switch Rly1 which constitutes a circuit changeover switch means through the transistor Tr1, the reactor L1 for voltage adjustment, the transistors Tr2 and Tr3. The AC conversion circuit 10 is reached.

  The voltage conversion circuit 101 is formed by the reactor L1, the transistors Tr1, Tr2, Tr3 and the diodes D1, D2, D3, D4. Then, the AC power converted by the DC / AC conversion circuit 10 is supplied to the commercial power supply system 15.

  A noise removing capacitor C5 is connected to the front stage of the DC / AC converter circuit 10. The changeover switch Rly1 is configured so that two sets of power relays Rly11 and Rly12 are interlocked as indicated by a broken line.

  Whether the upper power relay Rly11 in the figure, which is one of the two power relays Rly11 and Rly12, connects the commercial power system 15 side and the solar battery 1 side or the commercial power system 15 side and the storage battery 2 side. Switching function.

  The lower power relay Rly12 in the figure, which is the other of the two sets of power relays Rly11 and Rly12, connects the commercial power supply system 15 side and the storage battery 2 or the solar battery 1 side and the storage battery 2 via the voltage conversion circuit 101. And a function of switching between the two.

  Further, the disconnect switch SWd is connected between the diode D4 side of the voltage conversion circuit 101 and the other power relay Rly12 of the changeover switch Rly1. The disconnect switch SWd disconnects the storage battery 2 when the power of the solar battery 1 is sold to the commercial power supply system 15.

  The selector switch Rly1 used two power relays Rly11, Rly12 interlocked, but if two sets of power relays Rly11, Rly12 operate independently, the disconnect switch is SWd can be made unnecessary. Hereinafter, the operation of the electric circuit of FIG. 12 will be described separately for each case.

  FIG. 13 is an electric circuit diagram of the power conversion device 100 in FIG. 12 when the power of the solar cell 1 is sold to the commercial power supply system 15 or is consumed by the home appliance 16 such as a home refrigerator.

  In this case, the two sets of power relays Rly11 and Rly12 of the changeover switch Rly1 are interlocked and switched to the upper side, and the output of the solar cell 1 is output from the reactor L1, the transistor Tr3, and the diode D2 that perform the boosting function of the voltage conversion circuit 101. The voltage is boosted and further converted into single-phase AC of the commercial power supply system 15 via the DC / AC conversion circuit 10. Further, the separation switch SWd is OFF.

  FIG. 14 is an electric circuit diagram of the photovoltaic power conversion device 100 when the storage battery 2 is charged with the power of the solar battery 1 in FIG. In this case, the two sets of power relays Rly11 and Rly12 of the changeover switch Rly1 are interlocked and switched upward, and the disconnect switch SWd is turned on and closed.

  Therefore, the output of the solar cell 1 is boosted by the reactor L1, the transistor Tr3, and the diode D4 that exhibit the boosting function of the voltage conversion circuit 101, and charged to the storage battery 2.

  FIG. 15 is an electric circuit diagram of the power conversion apparatus 100 when the power of the storage battery 2 is sold to the commercial power supply system 15 in FIG. In this case, the two sets of power relays Rly11 and Rly12 of the changeover switch Rly1 constituting the circuit changeover switch means are switched to the lower side in conjunction with each other, and the separation switch SWd is OFF.

  Therefore, the output of the storage battery 2 is boosted by the reactor L1, the transistor Tr3, and the diode D2 of the voltage conversion circuit 101, and further converted into a single-phase AC of the commercial power supply system 15 via the DC / AC conversion circuit 10 for sale. .

(Other embodiments)
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows. For example, in the first embodiment described above, the storage battery is a stationary battery, but it may be a storage battery (battery) mounted on an electric vehicle (EV).

  That is, a storage battery in an electric vehicle placed in a garage can be charged with a solar cell on the roof, or surplus power of a battery of an electric vehicle (EV) can be sold to a commercial power supply system.

  Of course, the battery of the electric vehicle (EV) can be charged from the commercial power supply system. Similarly, the fuel cell may be a fuel cell mounted on an electric vehicle. Furthermore, in the first embodiment, a home appliance may be connected in front of the commercial power supply system 15 as in the second embodiment.

DESCRIPTION OF SYMBOLS 1 Solar cell 2 Storage battery 3 Fuel cell 4 Wind power generator 5-8, 11 Filter 5a, 5b Coil which forms the filter for noise cut 9 AC-DC converter circuit 10 DC-AC converter (inverter)
DESCRIPTION OF SYMBOLS 15 Commercial power supply system 100 Power converter device 101 Voltage step-down voltage converter C1, C2, C3, C4, C5 Capacitor D1, D2, D3, D4 Diode L1, Tr2, Tr3, D4 Voltage step-down voltage circuit L1 Reactor Rly1 changeover switch Power relays SW1 to SW5, SWa, SWb, Rly1 circuit switching switch means SWd disconnecting switch Tr1, Tr2, and Tr3 Transistors forming intermittent switch means Va Va DC AC conversion circuit input stage voltage

Claims (3)

An apparatus for charging a battery by the power generation unit and the commercial power system supplies the commercial power system by performing at least the voltage converter and the DC-AC converting the power generated by the power generating means,
A voltage conversion circuit comprising a reactor in which a current from the power generation means flows from a primary side toward a secondary side, and an intermittent switch means for controlling voltage supply to the reactor to convert voltage;
A DC / AC conversion circuit that performs DC / AC conversion on the output of the voltage conversion circuit and outputs the DC / AC conversion to the commercial power supply system; and a current that flows through the reactor in the voltage conversion circuit, Provide circuit selector switch means to selectively lead to the power system side ,
The storage battery is connected to the primary side and the secondary side of the reactor via the circuit changeover switch means, and at least via the circuit changeover switch means connected to the primary side of the reactor, Electric power characterized in that the electric power of the storage battery is supplied to the commercial power supply system or home electric appliance, and the storage battery is charged from the commercial power supply via the circuit changeover switch means connected to the secondary side of the reactor. Conversion device. In the apparatus for charging the storage battery with the power generation means and the commercial power supply system while performing at least voltage conversion and DC / AC conversion to supply the generated power of the power generation means to the commercial power supply system,
A voltage conversion circuit comprising a reactor in which a current from the power generation means flows from a primary side toward a secondary side, and an intermittent switch means for controlling voltage supply to the reactor to convert the voltage;
A DC / AC conversion circuit that performs the DC / AC conversion on the output of the voltage conversion circuit and outputs the DC / AC conversion to the commercial power supply system; and
Circuit switching switch means including a relay or a magnet switch provided separately from the intermittent switch means for selectively guiding the current flowing through the reactor in the voltage conversion circuit to the storage battery side and the commercial power supply system side Provided,
The intermittent switch means comprises switch elements provided on the primary side and the secondary side of the reactor,
With respect to the output of the voltage conversion circuit supplied via the reactor, the DC / AC conversion circuit performs the DC / AC conversion,
The circuit change-over switch means switches the current flowing through the reactor and one of the switch elements in the voltage conversion circuit to the storage battery side and the commercial power supply system side and leads the power conversion device . The power converter according to claim 2 , wherein the relay or the magnet switch selects the switch element to be used .

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