JP6892344B2 - Power conditioner system - Google Patents

Description

The present invention relates to a power conditioner system that supplies power supplied from a system and power supplied from an external DC power source such as a storage battery system to a load.

In recent years, by using both the power supplied from the grid and the power supplied from an external DC power source such as a power storage system and a solar power generation system installed in the customer, it is possible to level the power demand in one day. Systems aiming at continuous operation of loads (particularly important loads) in the event of a power failure are being promoted (see, for example, Non-Patent Document 1).

FIG. 4 shows an example of the power conditioner system 100 that plays a central role in the above system. As shown in the figure, the power conditioner system 100 includes system connection terminals Tu, To, and Tw connected to a single-phase three-wire system, and load connection terminals Tl, Tn connected to an important load. , The system side filter circuit F connected to these terminals Tu, To, Tw, Tl, Tn, the storage battery connection terminals Tp1 and Tn1 connected to the power storage system 11, and the storage battery side filter circuit Fa connected to these. , The first solar cell connection terminals Tp2 and Tn2 connected to the first photovoltaic power generation system 12, the first solar cell side filter circuit Fb connected to these, and the second photovoltaic power generation system 13. Second solar cell connection terminals Tp3, Tn3, a second solar cell side filter circuit Fc connected to these, and a power conversion circuit connected between the system side filter circuit F and the filter circuits Fa, Fb, Fc. It mainly includes CONV, CONV1, CONV2, CONV3, and a frame GND terminal Tfg.

In the power conditioner system 100, the switches S1 and S2 are in the closed state and the switches S3 and S4 are in the open state in the normal state in which an abnormality such as a power failure does not occur in the system. At this time, the power conditioner system 100 charges the storage battery while supplying [operation 1a] inexpensive system power at night to an important load via the switch S2, and [operation 2a] purchasing expensive system power during the day. In order to reduce the amount, the discharge power of the power storage system 11 is supplied to the critical load via the switches S1 and S2, and the generated power of the photovoltaic power generation systems 12 and 13 is important via the switches S1 and S2. It is possible to supply the load, to sell the surplus power generated by the photovoltaic power generation systems 12 and 13 to the system via the switch S1 and the like. At this time, the load connection terminal Tn is connected to the system connection terminal To, which is a neutral terminal, via the switch S2.

On the other hand, in the power conditioner system 100, the switches S1 and S2 are in the open state and the switches S3 and S4 are in the closed state in the event of a power failure. At this time, the power conditioner system 100 supplies the discharge power of the [operation 1b] power storage system 11 to the critical load via the switch S3, and [operation 2b] supplies the power generated by the photovoltaic power generation systems 12 and 13 to the switch S3. It is possible to supply important loads via At this time, the load connection terminal Tn is connected (grounded) to the frame GND terminal Tfg via the switch S4 to ensure safety.

"Nichicon's Home Energy Storage System How to Use Home Energy Storage System", [online], Nichicon Corporation, [Search June 27, 2017], Internet <URL http://www.nichicon.co.jp/ products / ess / living.html>

By the way, in the power conditioner system 100, in order to prevent the noise emitted from the power conversion circuits CONV, CONV1, CONV2, and CONV3 that perform the switching operation from leaking to the outside, as described above, the power conversion circuits CONV, CONV1, CONV2 , The system side filter circuit F and the filter circuits Fa, Fb, Fc are arranged so as to sandwich the CONV3. However, if the housing of the power conditioner system 100 is miniaturized in order to save space, the noise absorption capacity of the housing GND decreases, and the filter circuits F, Fa, Fb, and Fc are arranged as described above. However, there is a problem that the noise leaking to the outside cannot be sufficiently prevented.

5 and 6 show the average noise terminal voltage of the storage battery connection terminal Tp1 during a nighttime power failure. The measurement conditions are as follows.

[Measurement conditions common to FIGS. 5 and 6]
-Switches S1, S2: Open state-Switches S3, S4: Closed-Solar power generation systems 12, 13: Not generated-Important load: Rated load 2.5 kW
-Switching operation of power conversion circuits CONV and CONV1: On-Switching operation of power conversion circuits CONV2 and CONV3: Off [Measurement conditions in FIG. 5]
-As the storage battery side filter circuit, the storage battery side filter circuit Fa shown in FIG. 4 is connected in series in three stages [measurement conditions in FIG. 6].
-As the storage battery side filter circuit, the storage battery side filter circuit Fa shown in FIG. 4 is connected in series in 6 stages.

In both FIGS. 5 and 6, the average noise terminal voltage of the storage battery connection terminal Tp1 had a small margin with respect to the standard value shown by the thick solid line, especially in the vicinity of 0.15 MHz. Moreover, the measurement results of FIGS. 5 and 6 were almost the same. This indicates that when the housing GND is contaminated with noise, the leakage of noise is not reduced even if the number of stages of the filter circuit Fa on the storage battery side is increased.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power conditioner system capable of sufficiently reducing noise leaking to the outside even when the housing is miniaturized. To provide.

In order to solve the above problems, the power conditioner system according to the present invention includes a system connection terminal connected to a single-phase three-wire system, a load connection terminal connected to a load, and a system connection terminal. And the system side filter circuit connected to the load connection terminal, the power supply connection terminal connected to the external DC power supply, the power supply side filter circuit connected to the power supply connection terminal, the system connection terminal and the load connection. A power conditioner system including a power conversion circuit connected to a system side filter circuit on the opposite side of the terminal and connected to a power supply side filter circuit on the opposite side of the power supply connection terminal, wherein the power supply side filter circuit is , The common mode choke coil, the first Y capacitor connected to the housing GND of the power conditioner system provided on the power conversion circuit side of the common mode choke coil, and the power supply connection terminal rather than the common mode choke coil. It is characterized by including a second Y capacitor connected to a neutral terminal provided on the side and constituting a system connection terminal.

In this configuration, of the first Y capacitor and the second Y capacitor included in the power supply side filter circuit, the one provided on the power supply connection terminal side rather than the common mode choke coil constitutes the system connection terminal instead of the housing GND. It is connected to the neutral terminal. That is, in this configuration, the second Y capacitor provided near the power supply connection terminal is connected to the neutral terminal constituting the system connection terminal. Therefore, according to this configuration, even when the housing GND is contaminated with noise, the noise leaking from the power supply connection terminal to the outside is effectively generated by the combination of the common mode choke coil and the second Y capacitor. Can be reduced. This configuration is particularly effective when the housing of the power conditioner is relatively small and the noise absorption capacity of the housing GND is weak (when the housing is easily contaminated by noise).

Here, it has a plurality of power supply connection terminals connected to a plurality of external DC power supplies on a one-to-one basis, and a plurality of power supply-side filter circuits connected to a plurality of power supply connection terminals on a one-to-one basis. In a power conditioner system in which a plurality of external DC power supplies include a power storage system and a photovoltaic power generation system, a plurality of power supply connection terminals are connected to a storage battery connection terminal connected to the power storage system and a photovoltaic power generation system. Includes terminals for connecting solar cells. In this case, the plurality of power supply side filter circuits include a storage battery side filter circuit connected to the storage battery connection terminal and a solar cell side filter circuit connected to the solar cell connection terminal.

Further, in a power conditioner system in which a plurality of external DC power supplies further include a V2H system, the plurality of power supply connection terminals further include a V2H connection terminal connected to the V2H system. In this case, the power supply side filter circuit further includes a V2H side filter circuit connected to the V2H connection terminal.

In addition, the power conditioner system is one of a storage battery side filter circuit, a solar cell side filter circuit, and a V2H side filter circuit in order to suppress noise leakage from the neutral terminal of the system connection terminal to the system as much as possible. It is preferable that one includes a second Y capacitor.

According to the present invention, it is possible to provide a power conditioner system capable of sufficiently reducing noise leaking to the outside even when the housing is miniaturized.

It is a circuit diagram of the power conditioner system which concerns on this invention. It is a graph which shows the average noise terminal voltage of the power conditioner system which concerns on this invention. It is a circuit diagram of the power conditioner system which concerns on the modification of this invention. It is a circuit diagram of a conventional power conditioner system. It is a graph which shows the average noise terminal voltage of the conventional power conditioner system (when the filter circuit on a storage battery side is connected in 3 stages in series). It is a graph which shows the average noise terminal voltage of the conventional power conditioner system (when the filter circuit on a storage battery side is connected in 6 stages in series).

Hereinafter, an embodiment of the power conditioner system according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows the power conditioner system 10A according to the present invention. As shown in the figure, the power conditioner system 10A has a system connection terminal Tu, To, Tw connected to a single-phase three-wire system and a load connection terminal connected to a load (particularly important load). Tl, Tn, the system side filter circuit F connected to these terminals Tu, To, Tw, Tl, Tn, the storage battery connection terminals Tp1 and Tn1 connected to the power storage system 11, and the storage battery connected to these. The side filter circuit F1, the first solar cell connection terminals Tp2 and Tn2 connected to the first photovoltaic cell power generation system 12, the first solar cell side filter circuit F2 connected to these, and the second photovoltaic cell power generation system. It is connected between the second solar cell connection terminals Tp3, Tn3 connected to 13, the second solar cell side filter circuit F3 connected to these, the system side filter circuit F, and the filter circuits F1, F2, F3. It is equipped with power conversion circuits CONV, CONV1, CONV2, and CONV3.

The power conditioner system 10A further includes a frame GND terminal Tfg and a coil L. The coil L is provided in the wiring connecting the frame GND terminal Tfg and the housing GND.

Further, the power conditioner system 10A further includes switches S1, S2, S3 and S4. Of these, the switch S1 is provided in the wiring connecting the system connection terminal Tu and the system side filter circuit F, and the wiring connecting the system connection terminal Tw and the system side filter circuit F. The switch S2 is provided in the wiring connecting the system connection terminal Tu and the load connection terminal Tl, and the wiring connecting the system connection terminal To and the load connection terminal Tn. The switch S3 is provided in the wiring connecting the load connection terminal Tl and the system side filter circuit F, and the wiring connecting the load connection terminal Tn and the system side filter circuit F. Further, the switch S4 is provided in the wiring connecting the load connection terminal Tn and the frame GND terminal Tfg.

The storage battery side filter circuit F1 includes common mode choke coils L11 and L12, X capacitors C11 and Y capacitors C12 and C13 provided on the power conversion circuit CONV1 side of the common mode choke coils L11 and L12, and a common mode choke coil L11. , X capacitors C14 and Y capacitors C15, C16 provided on the storage battery connection terminals Tp1 and Tn1 side of L12 are included.

The Y capacitors C12 and C13 correspond to the "first Y capacitor" of the present invention. As shown in FIG. 1, the Y capacitors C12 and C13 (connection points between C12 and C13) are connected to the housing GND. On the other hand, the Y capacitors C15 and C16 correspond to the "second Y capacitor" of the present invention. As shown in FIG. 1, the Y capacitors C15 and C16 (connection points between C15 and C16) are connected to the system connection terminal To, which is a neutral terminal, instead of the housing GND.

The power conversion circuit CONV1 includes a DC / DC converter that operates in both directions. The power conversion circuit CONV1 boosts or lowers the discharge power of the power storage system 11 whose noise has been removed by the storage battery side filter circuit F1 and outputs the discharge power to the power conversion circuit CONV. Further, the power conversion circuit CONV1 boosts or steps down the DC power output by the power conversion circuit CONV, and outputs the DC power to the power storage system 11 via the storage battery side filter circuit F1. By the latter operation, the storage battery of the power storage system 11 is charged.

The first solar cell side filter circuit F2 includes a common mode choke coil L21, L22, an X capacitor C21 and a Y capacitor C22, C23 provided on the power conversion circuit CONV2 side of the common mode choke coils L21, L22, and a common mode. It includes an X capacitor C24 provided on the first solar cell connection terminals Tp2 and Tn2 side of the choke coils L21 and L22.

The Y capacitors C22 and C23 correspond to the "first Y capacitor" of the present invention. As shown in FIG. 1, the Y capacitors C22 and C23 (connection points between C22 and C23) are connected to the housing GND. On the other hand, the filter circuit F2 on the first solar cell side is provided with a capacitor corresponding to the "second Y capacitor" of the present invention (that is, on the side of the terminals Tp2 and Tn2 for connecting the first solar cell to the common mode choke coils L21 and L22. The Y capacitor) does not exist.

The power conversion circuit CONV2 comprises a DC / DC converter that operates in only one direction. The power conversion circuit CONV2 boosts or lowers the generated power of the first photovoltaic power generation system 12 whose noise has been removed by the first solar cell side filter circuit F2, and outputs the power to the power conversion circuit CONV.

The second solar cell side filter circuit F3 is the same as the first solar cell side filter circuit F2, the common mode choke coils L31 and L32, and the X capacitor provided on the power conversion circuit CONV3 side of the common mode choke coils L31 and L32. It includes C31 and Y capacitors C32 and C33, and X capacitors C34 provided on the second solar cell connection terminals Tp3 and Tn3 side of the common mode choke coils L31 and L32.

The Y capacitors C32 and C33 correspond to the "first Y capacitor" of the present invention. As shown in FIG. 1, the Y capacitors C32 and C33 (connection points between C32 and C33) are connected to the housing GND. On the other hand, the second solar cell side filter circuit F3 is provided with a capacitor corresponding to the "second Y capacitor" of the present invention (that is, on the second solar cell connection terminals Tp3 and Tn3 side of the common mode choke coils L31 and L32). The Y capacitor) does not exist.

The power conversion circuit CONV3, like the power conversion circuit CONV2, comprises a DC / DC converter that operates in only one direction. The power conversion circuit CONV3 boosts or lowers the generated power of the second photovoltaic power generation system 13 whose noise has been removed by the second solar cell side filter circuit F3, and outputs the power to the power conversion circuit CONV.

The power conversion circuit CONV comprises a DC / AC converter that operates in both directions. The power conversion circuit CONV converts the DC power output from one or more of the power conversion circuits CONV1, CONV2, and CONV3 into AC power corresponding to the system power of AC200V, and converts the DC power into AC power corresponding to the system power of AC200V, and the system or the system or through the system side filter circuit F. Output to critical load. Further, the power conversion circuit CONV converts the system power input via the system side filter circuit F into an appropriate DC power and outputs it to the power conversion circuit CONV1. This DC power is used to charge the storage battery.

The system side filter circuit F is a known type filter circuit including a common mode choke coil and one or more capacitors.

The power conditioner system 10A further includes a smoothing capacitor C. The smoothing capacitor C plays a role of reducing fluctuations in DC power between the power conversion circuit CONV and the power conversion circuits CONV1, CONV2, and CONV3.

As described above, in the power conditioner system 10A according to the present invention, the storage battery side filter circuit F1 is provided on the storage battery connection terminals Tp1 and Tn1 side of the common mode choke coils L11 and L12. A conventional power conditioner that has a 2Y capacitor) and the Y capacitors C15 and C16 (connection points between C15 and C16) are connected to the system connection terminal To, which is a neutral terminal, instead of the housing GND. Although it is different from the system 100, the configuration is common in other respects.

In the power conditioner system 10A according to the present invention, the switches S1 and S2 are in the closed state and the switches S3 and S4 are in the open state in the normal state when an abnormality such as a power failure does not occur in the system. At this time, the power conditioner system 10A, like the conventional power conditioner system 100, [operation 1a] charging the storage battery while supplying inexpensive system power at night to the important load via the switch S2, and [operation]. 2a] In order to reduce the purchase amount of expensive grid power in the daytime, the discharge power of the power storage system 11 is supplied to the important load via the switches S1 and S2, and [Operation 3a] Power generation of the photovoltaic power generation systems 12 and 13. It is possible to supply power to an important load via switches S1 and S2, and sell the surplus power generated by the photovoltaic power generation systems 12 and 13 to the grid via switch S1. is there. At the time of grid connection, the grid connection terminal To is grounded on the grid side.

On the other hand, in the power conditioner system 10A according to the present invention, the switches S1 and S2 are in the open state and the switches S3 and S4 are in the closed state during a power failure. At this time, the power conditioner system 10A supplies the discharge power of the [operation 1b] power storage system 11 to the critical load via the switch S3, as in the conventional power conditioner system 100, and [operation 2b] photovoltaic power generation. It is possible to supply the generated power of the systems 12 and 13 to the critical load via the switch S3, and the like.

FIG. 2 shows the average noise terminal voltage of the storage battery connection terminal Tp1 during a nighttime power failure. The measurement conditions are as follows.

[Measurement condition]
-Switches S1, S2: Open state-Switches S3, S4: Closed-Solar power generation systems 12, 13: Not generated-Important load: Rated load 2.5 kW
-Switching operation of power conversion circuits CONV and CONV1: On-Switching operation of power conversion circuits CONV2 and CONV3: Off

As shown in the figure, the average noise terminal voltage of the storage battery connection terminal Tp1 had a sufficient margin with respect to the standard value shown by the thick solid line at all the measured frequencies. This is because the Y capacitors C15 and C16 are added to the storage battery side filter circuit F1, so that the average noise terminal voltage of the storage battery connection terminal Tp1, that is, the noise leaking from the storage battery connection terminals Tp1 and Tn1 to the outside is significantly reduced. It shows that.

Although one embodiment of the power conditioner system according to the present invention has been described above, the configuration of the present invention is not limited to this.

For example, the power conditioner system according to the present invention is a V2H connection terminal Tp4 connected to a V2H (Vehicle to Home) system 14 that charges and discharges an in-vehicle large-capacity battery, as in the power conditioner system 10B shown in FIG. , Tn4 and a V2H side filter circuit F4 connected thereto may be further provided. Similar to the solar cell side filter circuits F2 and F3, the V2H side filter circuit F4 includes the common mode choke coils L41 and L42, and the X capacitors C41 and Y provided on the power conversion circuit CONV side of the common mode choke coils L41 and L42. It includes capacitors C42 and C43 and X capacitors C44 provided on the V2H connection terminals Tp4 and Tn4 side of the common mode choke coils L41 and L42. The Y capacitors C42 and C43 (connection points between C42 and C43) are connected to the housing GND.

According to this power conditioner system 10B, [operation 5a] supplying the discharge power of the in-vehicle large-capacity battery to an important load via switches S1 and S2 during normal operation, and [operation 3b] discharging the in-vehicle large-capacity battery during a power failure. It is also possible to supply power to the critical load via the switch S3.

In this case, the noise flowing out to the housing GND further increases, but as described above, the Y capacitors C15 and C16 (second Y capacitors) are provided on the storage battery connection terminals Tp1 and Tn1 side of the common mode choke coils L11 and L12. At the same time, if the Y capacitors C15 and C16 (connection points between C15 and C16) are connected to the system connection terminal To, which is a neutral terminal, the average noise terminal voltage of the storage battery connection terminal Tp1 is effectively reduced. be able to.

Further, the power conditioner system according to the present invention is connected to three or less external DC power sources selected from the power storage system 11, the first photovoltaic power generation system 12, the second photovoltaic power generation system 13, and the V2H system 14. It may be configured to be connected to five or more external DC power sources including some of them. Further, the power conditioner system according to the present invention may be configured to be connected to a fuel cell system as an external DC power source.

Further, for example, when it is desired to reduce the noise leaking from the V2H connection terminals Tp4 and Tn4 to the V2H system 14, a capacitor corresponding to the second Y capacitor (system connection which is a neutral terminal instead of the housing GND) is connected to the V2H side filter circuit F4. A Y capacitor connected to the terminal To) may be added.

Further, for example, noise leaking from the first solar cell connection terminals Tp2 and Tn2 to the first photovoltaic cell power generation system 12, and noise leaking from the second solar cell connection terminals Tp3 and Tn3 to the second photovoltaic cell power generation system 13. If you want to reduce both of these, add a capacitor corresponding to the second Y capacitor to both the first solar cell side filter circuit F2 and the second solar cell side filter circuit F3 (system connection terminal To, which is a neutral terminal instead of the housing GND). (Y capacitor connected to) may be added. However, if the number of capacitors corresponding to the 2nd Y capacitor is increased, the system connection terminal To, which is a neutral terminal, is contaminated with noise, and on the contrary, a sufficient noise leakage suppression effect cannot be obtained. It is necessary to decide the necessity of addition in.

10A, 10B Power conditioner system 11 Power storage system 12 1st photovoltaic power generation system 13 2nd photovoltaic power generation system 14 V2H system CONV power conversion circuit (bidirectional DC / AC converter)
CONV1 power conversion circuit (bidirectional DC / DC converter)
CONV2 power conversion circuit (DC / DC converter)
CONV3 power conversion circuit (DC / DC converter)
F system side filter circuit F1 Storage battery side filter circuit (external DC power supply)
F2 1st solar cell side filter circuit (external DC power supply)
F3 2nd solar cell side filter circuit (external DC power supply)
F4 V2H side filter circuit (external DC power supply)
Tu, To, Tw System connection terminal Tl, Tn Load connection terminal Tfg Frame GND terminal Tp1, Tn1 Storage battery connection terminal (power supply connection terminal)
Tp2, Tn2 1st solar cell connection terminal (power supply connection terminal)
Tp3, Tn3 2nd solar cell connection terminal (power supply connection terminal)
Tp4, Tn4 V2H connection terminal (power supply connection terminal)

Claims (4)

A system connection terminal connected to a single-phase three-wire system, a load connection terminal connected to a load, a system connection terminal, a system side filter circuit connected to the load connection terminal, and an external filter. The power supply connection terminal connected to the DC power supply, the power supply side filter circuit connected to the power supply connection terminal, and the system side filter circuit connected to the system connection terminal and the opposite side of the load connection terminal. A power conditioner system including a power conversion circuit connected to the power supply side filter circuit on the opposite side of the power supply connection terminal.
The power supply side filter circuit
Common mode choke coil and
A first Y capacitor connected to the housing GND of the power conditioner system provided on the power conversion circuit side of the common mode choke coil, and
A second Y capacitor connected to the neutral terminal constituting the system connection terminal provided on the power supply connection terminal side of the common mode choke coil, and
A power conditioner system characterized by including. It has a plurality of power supply connection terminals connected to the plurality of external DC power supplies on a one-to-one basis, and a plurality of power supply side filter circuits connected to the plurality of power supply connection terminals on a one-to-one basis.
The plurality of external DC power sources include a power storage system and a photovoltaic power generation system.
The plurality of power supply connection terminals include a storage battery connection terminal connected to the power storage system and a solar cell connection terminal connected to the solar power generation system.
The plurality of power supply side filter circuits include a storage battery side filter circuit connected to the storage battery connection terminal and a solar cell side filter circuit connected to the solar cell connection terminal. Power conditioner system described in. The plurality of external DC power supplies further include a V2H system.
The plurality of power supply connection terminals further include a V2H connection terminal connected to the V2H system.
The power conditioner system according to claim 2, wherein the plurality of power supply side filter circuits further include a V2H side filter circuit connected to the V2H connection terminal. The power conditioner system according to claim 3, wherein one of the storage battery side filter circuit, the solar cell side filter circuit, and the V2H side filter circuit includes the second Y capacitor.

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