CN118473063A - Charging systems, energy storage systems and vehicles - Google Patents

Abstract

The present application discloses a charging system, an energy storage system and a vehicle, and belongs to the field of charging. The charging system includes: a switch tube module, which is connected between a power grid and an energy storage device; an active leakage current suppression circuit, which is respectively connected to the ground wire of the power grid and the switch tube module, and the active leakage current suppression circuit is used to generate a reverse leakage current whose amplitude difference with the leakage current in the charging system does not exceed the target range and whose phase is opposite. The charging system of the present application, combined with a symmetrical switch control strategy and a switch tube module multiplexing strategy, effectively realizes power frequency leakage current suppression and high-frequency leakage current suppression, and the charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

Description

Charging systems, energy storage systems and vehicles

Technical Field

The present application belongs to the field of charging, and in particular relates to a charging system, an energy storage system and a vehicle.

Background Art

For non-isolated electric vehicle on-board chargers (OBCs), since the AC side is directly connected to the DC side, the common-mode voltage caused by the AC input grid side and high-frequency switches will charge and discharge the safety Y capacitors and distributed Y capacitors in the circuit to form common-mode current, that is, leakage current. If the leakage current value exceeds the detection threshold, the external charging device will interrupt the charging process, thereby affecting the user experience. In the related technology, there is a lack of effective leakage current suppression methods, and the leakage current suppression cost is high.

Summary of the invention

The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a charging system, an energy storage system and a vehicle, which can effectively achieve power frequency leakage current suppression and high frequency leakage current suppression, and has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

In a first aspect, the present application provides a charging system, the system comprising:

A switch tube module, wherein the switch tube module is connected between the power grid and the energy storage device;

An active leakage current suppression circuit is respectively connected to the ground wire of the power grid and the switch tube module, and is used to generate a reverse leakage current whose amplitude difference from the leakage current in the charging system does not exceed a target range and has an opposite phase.

According to the charging system of the present application, combined with the symmetrical switch control strategy and the switch tube module multiplexing strategy, the power frequency leakage current suppression and high-frequency leakage current suppression are effectively achieved. The charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

According to one embodiment of the present application, the switch tube module includes:

A main switch module, wherein the main switch module is connected between the power grid and the energy storage device;

An auxiliary switch tube module, the auxiliary switch tube module is connected between the power grid and the energy storage device; the auxiliary switch tube module is used to provide an excitation source for the active leakage current suppression circuit;

The main switch tube module and the auxiliary switch tube module are connected in parallel.

According to one embodiment of the present application, the switch tube module further includes:

A first inductor module, wherein the first inductor module and the main switch module are sequentially connected between the power grid and the energy storage device.

According to an embodiment of the present application, the main switch module includes a first main switch module and a second main switch module connected in parallel, the first inductor module includes a second inductor and a third inductor,

The first main switch module includes a first sub-switch and a second sub-switch connected in series, and a midpoint between the first sub-switch and the second sub-switch is connected to a first phase line of the charging system via the second inductor;

The second main switch module includes a third sub-switch and a fourth sub-switch connected in series, and a midpoint between the third sub-switch and the fourth sub-switch is connected to a second phase line of the charging system via the third inductor.

According to an embodiment of the present application, the second inductor and the third inductor have the same inductance value.

According to an embodiment of the present application, the main switch tube module adopts a symmetrical switch control strategy to suppress high-frequency leakage current in the charging system.

According to one embodiment of the present application, the switch tube module further includes:

A second inductor module, wherein the second inductor module and the auxiliary switch tube module are sequentially connected between the power grid and the energy storage device, and the second inductor module and the auxiliary switch tube module are connected to the active leakage current suppression circuit.

According to an embodiment of the present application, the auxiliary switch module includes a first auxiliary switch module and a second auxiliary switch module connected in parallel, and the second inductor module includes a fourth inductor and a fifth inductor; wherein,

The first auxiliary switch module includes a fifth sub-switch and a sixth sub-switch connected in series, and a midpoint between the fifth sub-switch and the sixth sub-switch is connected to a third phase line of the charging system and an input end of the active leakage current suppression circuit via the fourth inductor;

The second auxiliary switch module includes a seventh sub-switch and an eighth sub-switch connected in series, and a midpoint between the seventh sub-switch and the eighth sub-switch is connected to the third phase line and an input end of the active leakage current suppression circuit via the fifth inductor.

According to an embodiment of the present application, the fourth inductor and the fifth inductor have the same inductance, and the inductance of the fourth inductor is twice the inductance of the second inductor.

According to one embodiment of the present application, the active leakage current suppression circuit includes:

A power supply device, wherein an input end of the power supply device is connected to two input ends of the auxiliary switch tube module included in the switch tube module;

a first transformer, wherein a primary side of the first transformer is connected to the power supply device;

A first Y capacitor, wherein a first end of a secondary side of the first transformer is connected to the ground line via the first Y capacitor, and a second end of the secondary side is connected to a phase line and a neutral line of the charging system.

According to one embodiment of the present application, the power supply device includes:

A third low-pass filter and a fourth filter, wherein the output end of the fourth filter is connected to the primary side of the first transformer, and the input end of the third low-pass filter is connected to the fourth inductor and the fifth inductor included in the auxiliary switch module;

A fourth switch, wherein the fourth switch is connected in parallel with the two input ports of the third low-pass filter, and the fourth switch is arranged between the two input ends of the auxiliary switch tube module.

According to one embodiment of the present application, it also includes:

A plurality of first switches, wherein the plurality of phase lines and the neutral line of the charging system are respectively provided with the first switches;

A plurality of fourth capacitors are arranged between the target phase line and the neutral line, and one end of the fourth capacitor connected to the neutral line is also connected to the active leakage current suppression circuit.

According to one embodiment of the present application, it also includes:

A common-mode inductor module is connected between the power grid and the switch tube module, and the common-mode inductor module is arranged on the phase line of the charging system.

According to an embodiment of the present application, the switch tube module adopts a symmetrical switch control strategy.

In a second aspect, the present application provides an energy storage system, comprising:

Energy storage devices;

As described in the first aspect, the charging system is used to connect between a power grid and the energy storage device.

In a third aspect, the present application provides a vehicle, the vehicle comprising:

An energy storage system as described in the second aspect.

According to the vehicle of the present application, by setting a switch tube module and an active leakage current suppression circuit, combined with a symmetrical switch control strategy and a switch tube module multiplexing strategy, the power frequency leakage current suppression and high-frequency leakage current suppression are effectively achieved. The charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

The above one or more technical solutions in the embodiments of the present application have at least one of the following technical effects:

By setting up a switch tube module and an active leakage current suppression circuit, combined with a symmetrical switch control strategy and a switch tube module multiplexing strategy, the power frequency leakage current suppression and high-frequency leakage current suppression can be effectively achieved. The charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

Furthermore, in the single-phase AC charging mode, the auxiliary switch tube module is reused to provide an excitation source for the active leakage current suppression circuit, and the main switch tube adopts a symmetrical switching strategy to effectively achieve power frequency leakage current suppression and high-frequency leakage current suppression; in the three-phase AC charging mode, the auxiliary switch tube is connected in parallel as a phase bridge arm to charge the energy storage device, so that in both single-phase and three-phase charging modes, power frequency leakage current suppression and high-frequency leakage current suppression can be effectively achieved.

Furthermore, by setting a symmetrical first auxiliary switch module and a second auxiliary switch module, the auxiliary switch tube can be used as a high-frequency inverter module in the single-phase AC charging mode to provide an excitation source input for the active leakage current suppression circuit, thereby realizing power frequency leakage current suppression; in the three-phase AC charging mode, the first auxiliary switch module and the second auxiliary switch module are connected in parallel as the bridge arm of a certain phase line to charge the energy storage device, thereby realizing the reuse of the auxiliary switch tube, simplifying the circuit structure, effectively reducing the control complexity and design cost, and having high reliability and a wide range of applicable scenarios.

Furthermore, by setting a third low-pass filter, a fourth filter and a fourth switch, the energy storage device in the system can be used as an excitation source without setting an additional excitation source, which further simplifies the circuit structure and effectively reduces the control complexity and design cost.

Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

FIG1 is a schematic diagram of a charging system according to an embodiment of the present application;

FIG. 2 is a second schematic diagram of the structure of the charging system provided in an embodiment of the present application.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and/or" in the specification and claims represents at least one of the connected objects, and the character "/" generally indicates that the objects associated with each other are in an "or" relationship.

The charging system and vehicle provided in the embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

As shown in FIG. 1 , the charging system includes: a switch tube module and an active leakage current suppression circuit 100 .

The switch tube module can be arranged in a non-isolated charger.

The non-isolated charger is connected between the power grid 10 and the energy storage device 70 to achieve conversion from AC to DC.

The energy storage device 70 may include various types of energy storage batteries and the like.

The power grid 10 may include a single-phase input power grid or a three-phase input power grid.

In some embodiments, a switch module 110 may be provided in each phase line and neutral line of the three-phase input power grid to control the on and off of the corresponding branch, thereby realizing switching between the single-phase charging mode and the three-phase charging mode.

As shown in FIG. 1 , in some embodiments, the charging system may further include: a switch module 110 , which may be disposed on each phase line and a neutral line between the non-isolated charger and the power grid 10 .

It can be understood that the charging system may include a charging pile end and a vehicle end, wherein the charging pile end is provided with power input by an AC source of the power grid, and the vehicle end includes a non-isolated charger, which is connected between the power grid 10 and the energy storage device 70, and converts AC into DC through the non-isolated charger to charge the energy storage device 70.

The charging system may include a plurality of first filters.

Wherein, the switch tube module is arranged between the two first filters.

The first filter may be an EMI filter.

Continuing to refer to FIG. 1 , in some embodiments, the charging system may further include a common mode inductor module 30 .

In this embodiment, the common mode inductor module 30 may be disposed in a non-isolated charger.

The common-mode inductor module 30 is connected between the power grid 10 and the switch tube module, and the common-mode inductor module 30 is arranged on the phase line of the charging system.

In some embodiments, when the charging system is in a three-phase AC charging mode, the common-mode inductor module 30 may include a plurality of sub-common-mode inductors L1 .

In this embodiment, as shown in FIG. 2 , at least one sub-common mode inductor L1 is correspondingly disposed on each phase line.

Taking the first filter as an EMI filter as an example, the plurality of first filters may include a first EMI filter 20 and a second EMI filter 60 , and the second EMI filter 60 is used to be connected to the energy storage device 70 .

The first EMI filter 20 is connected to the second EMI filter 60 via the sub-common mode inductor L1 arranged on each phase line and the switch tube module correspondingly connected to the sub-common mode inductor L1.

When the charging system is in a three-phase AC charging mode, the common mode inductor module 30 can be used to suppress the high-frequency leakage current generated by the charging system.

The switch tube module is connected between the power grid 10 and the energy storage device 70 .

In some embodiments, the switch tube module adopts a symmetrical switching strategy to suppress high-frequency leakage current generated in a single-phase AC charging mode.

The active leakage current suppression circuit 100 is connected to the ground wire PE of the power grid 10 and the switch tube module respectively.

When the active leakage current suppression circuit 100 is in operation, it is used to generate a reverse leakage current whose amplitude does not differ from the leakage current in the circuit of the charging system by more than the target range and whose phase is opposite, and inject it into the circuit of the charging system, so that the net leakage current on the ground line approaches 0, thereby achieving leakage current suppression.

The target range is a smaller range that can be customized by the user.

The difference can be a difference or a ratio, etc.

It can be understood that, when the difference does not exceed the target range, it can be approximately considered that the magnitude of the reverse leakage current is the same or substantially the same as the magnitude of the leakage current in the circuit of the charging system.

The switch module 110 is used to switch the working mode of the power grid 10 .

The working mode includes a single-phase AC charging mode or a three-phase AC charging mode.

In some embodiments, the switch module 110 may also control the working state of the active leakage current suppression circuit 100 .

The working status includes working or not working.

When the charging system is in the single-phase AC charging mode, the active leakage current suppression circuit 100 operates.

When the charging system is in the three-phase AC charging mode, the active leakage current suppression circuit 100 does not work.

It should be noted that, in the actual implementation process, when the charging system is in a single-phase AC charging mode, the active leakage current suppression circuit 100 works to generate a reverse leakage current whose difference in amplitude from the leakage current I _leak in the circuit of the charging system does not exceed the target range and whose phase is opposite, thereby achieving power frequency leakage current suppression.

The switch tube module adopts a symmetrical switching control strategy to achieve a negative jump trend of the same amplitude in the negative pole potential of the DC bus when the positive pole potential of the DC bus jumps, thereby suppressing the high-frequency leakage current generated.

When the charging system is in a three-phase AC charging mode, there is no need to suppress the power frequency leakage current, and the active leakage current suppression circuit 100 may not work; the high-frequency leakage current generated may be suppressed by the common-mode inductor module 30 .

According to the charging system provided in the embodiment of the present application, by setting a switch tube module and an active leakage current suppression circuit, combined with a symmetrical switch control strategy and a switch tube module multiplexing strategy, the power frequency leakage current suppression and high-frequency leakage current suppression are effectively achieved. The charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

Continuing to refer to FIG. 1 , in some embodiments, the switch tube module includes: a main switch tube module 50 and an auxiliary switch tube module 90 .

In this embodiment, the main switch module 50 is connected between the power grid 10 and the energy storage device 70 .

The auxiliary switch tube module 90 is connected between the power grid 10 and the energy storage device 70 ; the auxiliary switch tube module 90 is used to provide an excitation source for the active leakage current suppression circuit 100 .

Continuing to refer to FIG. 1 , in some embodiments, the switch tube module may further include: a first inductor module 40 .

In this embodiment, the first inductor module 40 and the main switch module 50 are connected between the power grid 10 and the energy storage device 70 in sequence.

In some embodiments, the main switch module 50 adopts a symmetrical switch control strategy to suppress high-frequency leakage current in the charging system in a single-phase AC charging mode.

The second inductor module 80 and the auxiliary switch module 90 are connected between the power grid 10 and the energy storage device 70 in sequence.

In some embodiments, the switch tube module may further include: a second inductor module 80 .

In this embodiment, the second inductor module 80 and the auxiliary switch module 90 are connected between the power grid 10 and the energy storage device 70 in sequence.

The auxiliary switch tube module 90 is used to provide an excitation source for the active leakage current suppression circuit 100 in a single-phase AC charging mode.

In the actual implementation process, when the charging system is in single-phase AC charging mode, the main switch tube module 50 adopts a symmetrical switching control strategy to ensure that when the positive pole potential of the DC bus jumps, the negative pole potential of the DC bus can simultaneously jump in the opposite direction with the same amplitude, thereby achieving the effect of high-frequency leakage current offset, and further suppressing the leakage current generated in single-phase AC charging.

When the charging system is in a three-phase AC charging mode, the main switch tube module 50 and the auxiliary switch tube module 90 are respectively connected to corresponding phase lines to charge the energy storage device 70 .

According to the charging system provided in the embodiment of the present application, by setting the main switch tube module 50 and the auxiliary switch tube module 90, the switch tube modules can be reused to enable each switch tube module to realize different functions in different charging modes, and the power frequency leakage current suppression and high-frequency leakage current suppression can be effectively realized in both single-phase and multi-phase charging modes.

As shown in FIG. 2 , in some embodiments, the main switch module 50 may include: a first main switch module and a second main switch module connected in parallel, and the first inductor module 40 includes a second inductor L2 and a third inductor L3 .

In this embodiment, the first main switch module forms one bridge arm, and the second main switch module forms another bridge arm.

The first main switch module includes a first sub-switch S1 and a second sub-switch S2 connected in series, and a midpoint between the first sub-switch S1 and the second sub-switch S2 is connected to a first phase line of the charging system via a second inductor L2.

The second main switch module includes a third sub-switch S3 and a fourth sub-switch S4 connected in series, and a midpoint between the third sub-switch S3 and the fourth sub-switch S4 is connected to a second phase line of the charging system via a third inductor L3.

In some embodiments, the second inductor L2 and the third inductor L3 have the same inductance to achieve symmetry.

In the single-phase AC charging operation mode, the first sub-switch S1 and the fourth sub-switch S4 are switched synchronously, and the second sub-switch S2 and the third sub-switch S3 are switched synchronously, so as to implement a symmetrical switch control strategy.

The following description is made by taking the example that the first phase line is the A phase line and the second phase line is the B phase line.

When the charging system is in single-phase AC charging mode, the first main switch module serves as an L-phase bridge arm, and the second main switch module serves as an N-phase bridge arm to charge the energy storage device 70 .

At the same time, the first main switch module and the second main switch module switch symmetrically, thereby suppressing high-frequency leakage current generated during the operation of the circuit.

When the charging system is in a three-phase AC charging mode, the first main switch module serves as an A-phase bridge arm, and the second main switch module serves as a B-phase bridge arm to charge the energy storage device 70 .

2 , in some embodiments, the auxiliary switch module 90 may include a first auxiliary switch module and a second auxiliary switch module connected in parallel, and the second inductor module 80 may include a fourth inductor L4 and a fifth inductor L5 .

In this embodiment, the first auxiliary switch module forms one bridge arm, and the second auxiliary switch module forms another bridge arm.

The first auxiliary switch module includes a fifth sub-switch S5 and a sixth sub-switch S6 connected in series, and a midpoint between the fifth sub-switch S5 and the sixth sub-switch S6 is connected to the third phase line of the charging system via a fourth inductor L4.

In some embodiments, the midpoint between the fifth sub-switch S5 and the sixth sub-switch S6 may also be connected to the input terminal of the active leakage current suppression circuit 100 via the fourth inductor L4 .

The second auxiliary switch module includes a seventh sub-switch S7 and an eighth sub-switch S8 connected in series, and a midpoint between the seventh sub-switch S7 and the eighth sub-switch S8 is connected to the third phase line of the charging system via a fifth inductor L5.

In some embodiments, the midpoint between the seventh sub-switch S7 and the eighth sub-switch S8 is also connected to the input terminal of the active leakage current suppression circuit 100 via the fifth inductor L5 .

In some embodiments, the fourth inductor L4 and the fifth inductor L5 have the same inductance, and the inductance of the fourth inductor L4 is twice the inductance of the second inductor L2.

When the charging system is in single-phase AC charging mode, the high-frequency inversion function is realized by the first auxiliary switch module and the second auxiliary switch module to provide an excitation source input for the active leakage current suppression circuit 100. As shown in FIG2 , in the actual implementation process, a controller and a leakage current sampling module electrically connected to the controller may be provided, and the controller controls the leakage current sampling module to sample the leakage current I _leak on the ground line.

When the charging system is in a three-phase AC charging mode, the first auxiliary switch module and the second auxiliary switch module work in parallel as a C-phase bridge arm to charge the energy storage device 70 .

According to the charging system provided in the embodiment of the present application, by setting the first auxiliary switch module and the second auxiliary switch module, the auxiliary switch tube can be used as a high-frequency inverter module in the single-phase AC charging mode to provide an excitation source input for the active leakage current suppression circuit 100, thereby realizing power frequency leakage current suppression; in the three-phase AC charging mode, the first auxiliary switch module and the second auxiliary switch module are connected in parallel as the bridge arm of a certain phase line to charge the energy storage device 70, thereby realizing the reuse of the auxiliary switch tube, simplifying the circuit structure, effectively reducing the control complexity and design cost, and having high reliability and a wide range of applicable scenarios.

The structure of the active leakage current suppression circuit 100 is described in detail below.

Continuing to refer to FIG. 2 , in some embodiments, the active leakage current suppression circuit 100 may include: a power supply device, a first transformer T1 , and a first Y capacitor CY1 .

In this embodiment, the power supply means is a means for providing excitation.

In some embodiments, the input end of the power supply device is connected to two input ends of the auxiliary switch tube module 90 included in the switch tube module, so that the auxiliary switch tube module 90 provides an excitation source.

The primary side of the first transformer T1 is connected to the power supply device, and the first end of the secondary side of the first transformer T1 is connected to the ground line via the first Y capacitor CY1 to provide a voltage reference.

The second end of the secondary side of the first transformer T1 is connected to the phase line and the neutral line of the charging system, and thus connected to the switching tube module, so as to inject a reverse leakage current whose amplitude difference from the leakage current in the circuit of the charging system does not exceed the target range and has an opposite phase into the circuit of the charging system, thereby achieving leakage current suppression.

In some embodiments, the injection point of the reverse leakage current may include the neutral point of the capacitor module before the first filter, the neutral point of the capacitor module after the first filter, or the neutral point of the capacitor module before the energy storage device 70, etc. For example, as shown in Figure 2, a capacitor module can be set before the energy storage device 70, and the capacitor module includes a second capacitor CY2 and a third capacitor CY3 connected in series. The injection point of the reverse leakage current is the neutral point between the second capacitor CY2 and the third capacitor CY3, which is not limited in this application.

The capacitor module is arranged between the phase line and the neutral line.

In some embodiments, the capacitor module may include a first sub-capacitor and a second sub-capacitor connected in series.

The first sub-capacitor and the second sub-capacitor are connected in series and arranged between the L line and the N line of the power grid 10 . The neutral point of the capacitor module is the potential midpoint between the first sub-capacitor and the second sub-capacitor.

In some embodiments, the power supply device may include: a third low-pass filter, a fourth filter, and a fourth switch K41.

In this embodiment, the fourth filter may include but is not limited to: a π-type filter or other types of EMI filters, etc.

The output end of the fourth filter is connected to the primary side of the first transformer T1 , as shown in FIG. 2 . The fourth filter may be the EMI filter in the figure.

In some embodiments, the input end of the third low-pass filter is connected to the fourth inductor L4 and the fifth inductor L5 included in the auxiliary switch module 90 , as shown in FIG. 2 , and the third low-pass filter may be the low-pass filter in the figure.

The third low-pass filter and the fourth filter are connected in series, the fourth switch K41 is connected in parallel with two input ports of the third low-pass filter, and the fourth switch K41 is arranged between two input ends of the auxiliary switch module 90 included in the switch module.

When the fourth switch K41 is closed, the active leakage current suppression circuit 100 is short-circuited and does not work.

When the fourth switch K41 is disconnected, the third low-pass filter is connected to both ends of the energy storage device 70 via the auxiliary switch tube, and the high-voltage direct current output by the energy storage device 70 is used as an excitation source for the active leakage current suppression circuit 100, so that the active leakage current suppression circuit 100 works to generate a reverse leakage current, which is injected into the circuit of the charging system through the secondary side of the first transformer T1.

Of course, in other embodiments, the power supply device may also be a low-voltage battery, alternating current from the power grid 10, or an active leakage current suppression excitation circuit, which is not limited in the present application.

According to the charging system provided in the embodiment of the present application, by setting a third low-pass filter, a fourth filter and a fourth switch, the energy storage device 70 in the system can be used as an excitation source without setting an additional excitation source, thereby further simplifying the circuit structure and effectively reducing the control complexity and design cost.

In some embodiments, the charging system may further include: a plurality of first switches and a plurality of fourth capacitors.

In this embodiment, as shown in FIG. 2 , the plurality of first switches may include a switch K81 , a switch K82 , a switch K83 , and a switch K84 .

Continuing to refer to FIG. 2 , the plurality of fourth capacitors may include C1 , C2 , and C3 .

At least one first switch is respectively provided on the phase line and the neutral line of the power grid 10 . When the first switch is closed, the branch circuit provided by the first switch is conductive.

The fourth capacitor is arranged between the target phase line and the neutral line.

The target phase line includes at least one phase line among the A phase line, the B phase line and the C phase line.

One end of the fourth capacitor connected to the neutral line is also connected to the second end of the secondary side of the first transformer T1 of the active leakage current suppression circuit 100 .

One end of the fourth capacitor connected to the neutral line is also connected to any one of the multiple phase lines.

By controlling the on/off state of the first switch, switching between the single-phase charging mode and the three-phase charging mode can be achieved.

In some embodiments, the first switch may include but is not limited to: a relay, etc.

For example, with continued reference to FIG. 2 , when the switch K81 and the switch K84 are closed, the charging system operates in a single-phase AC input mode.

In the single-phase AC input mode, the fourth switch K41 is controlled to be disconnected, and the third low-pass filter is connected to both ends of the energy storage device 70 through the auxiliary switch tube. The high-voltage direct current output by the energy storage device 70 is used as an excitation source for the active leakage current suppression circuit 100, thereby making the active leakage current suppression circuit 100 work.

When the switch K81 , the switch K82 , and the switch K83 are closed, the charging system operates in a three-phase AC input mode.

In the three-phase AC input mode, the fourth switch K41 is controlled to be closed, so that the active leakage current suppression circuit 100 does not work. In this case, the first auxiliary switch module and the second auxiliary switch module work in parallel as a C-phase bridge arm to charge the energy storage device 70.

According to the charging system provided in the embodiment of the present application, by setting multiple switches, compatibility with single-phase input and three-phase input can be achieved, and the power frequency leakage current and high-frequency leakage current can be suppressed in any charging mode, further improving the applicable scenarios and scope of the charging system.

The embodiment of the present application also provides an energy storage system.

The energy storage system comprises: an energy storage device and a charging system as described in any of the above embodiments.

Among them, the charging system is used to connect between the power grid and the energy storage device to charge the energy storage device.

In the actual implementation process, in the single-phase AC charging mode, the auxiliary switch tube module 90 is reused to provide an excitation source for the active leakage current suppression circuit to suppress the power frequency leakage current; the main switch tube module 50 adopts a symmetrical switching strategy to suppress high-frequency leakage current.

In the three-phase AC charging mode, the auxiliary switch tube module 90 is connected in parallel as a bridge arm of a certain phase to charge the energy storage device.

According to the energy storage system provided in the embodiment of the present application, by setting a switch tube module and an active leakage current suppression circuit, in a single-phase AC charging mode, the auxiliary switch tube module is reused to provide an excitation source for the active leakage current suppression circuit, and the main switch tube adopts a symmetrical switching strategy to effectively achieve power frequency leakage current suppression and high-frequency leakage current suppression; in a three-phase AC charging mode, the auxiliary switch tube is connected in parallel as a bridge arm of a certain phase to charge the energy storage device; the charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

An embodiment of the present application also provides a vehicle.

The vehicle includes: an energy storage system as described in any of the above embodiments.

In this embodiment, the energy storage system is disposed on the vehicle body to supply power to the vehicle.

In the actual implementation process, in the single-phase AC charging mode, the auxiliary switch tube module 90 is reused to provide an excitation source for the active leakage current suppression circuit to suppress the power frequency leakage current; the main switch tube module 50 adopts a symmetrical switching strategy to suppress high-frequency leakage current.

In the three-phase AC charging mode, the auxiliary switch tube module 90 is connected in parallel as a bridge arm of a certain phase to charge the energy storage device.

According to the vehicle provided in the embodiment of the present application, by setting a switch tube module and an active leakage current suppression circuit, combined with a symmetrical switch control strategy and a switch tube module multiplexing strategy, the power frequency leakage current suppression and high-frequency leakage current suppression are effectively achieved. The charging system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises one..." does not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be noted that the scope of the method and device in the embodiment of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM/RAM, a disk, or an optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims (16)

1. A charging system, comprising:

The switching tube module is connected between the power grid and the energy storage device;

And the active leakage current suppression circuit is respectively connected with the ground wire of the power grid and the switch tube module and is used for generating reverse leakage current with the amplitude difference degree of the leakage current in the charging system not exceeding a target range and opposite in phase.

2. The charging system of claim 1, wherein the switching tube module comprises:

The main switch tube module is connected between the power grid and the energy storage device;

the auxiliary switching tube module is connected between the power grid and the energy storage device; the auxiliary switching tube module is used for providing an excitation source for the active leakage current suppression circuit;

The main switching tube module and the auxiliary switching tube module are connected in parallel.

3. The charging system of claim 2, wherein the switching tube module further comprises:

the first inductance module and the main switch tube module are sequentially connected between the power grid and the energy storage device.

4. The charging system of claim 3, wherein the main switching tube module comprises a first main switching module and a second main switching module connected in parallel, the first inductance module comprises a second inductance and a third inductance,

The first main switch module comprises a first sub switch and a second sub switch which are connected in series, and the midpoint between the first sub switch and the second sub switch is connected with a first phase line of the charging system through the second inductor;

The second main switch module comprises a third sub-switch and a fourth sub-switch which are connected in series, and a midpoint between the third sub-switch and the fourth sub-switch is connected with a second phase line of the charging system through the third inductor.

5. The charging system of claim 4, wherein the second inductance and the third inductance have the same inductance value.

6. The charging system of claim 2, wherein the main switching tube module employs a symmetrical switching control strategy for suppressing high frequency leakage currents in the charging system.

7. The charging system of claim 4, wherein the switching tube module further comprises:

the second inductance module and the auxiliary switching tube module are sequentially connected between the power grid and the energy storage device, and the second inductance module and the auxiliary switching tube module are connected with the active leakage current suppression circuit.

8. The charging system of claim 7, wherein the auxiliary switching tube module comprises a first auxiliary switching module and a second auxiliary switching module connected in parallel, the second inductance module comprising a fourth inductance and a fifth inductance; wherein,

The first auxiliary switch module comprises a fifth sub switch and a sixth sub switch which are connected in series, and the midpoint between the fifth sub switch and the sixth sub switch is connected with a third phase line of the charging system and the input end of the active leakage current suppression circuit through the fourth inductor;

the second auxiliary switch module comprises a seventh sub-switch and an eighth sub-switch which are connected in series, and a midpoint between the seventh sub-switch and the eighth sub-switch is connected with the third phase line and the input end of the active leakage current suppression circuit through the fifth inductor.

9. The charging system of claim 8, wherein the inductance of the fourth inductor and the inductance of the fifth inductor are the same, and the inductance of the fourth inductor is twice the inductance of the second inductor.

10. The charging system according to any one of claims 1 to 9, wherein the active leakage current suppressing circuit includes:

The input end of the power supply device is connected with two input ends of an auxiliary switching tube module included in the switching tube module;

the primary side of the first transformer is connected with the power supply device;

And the first end of the secondary side of the first transformer is connected with the ground wire through the first Y capacitor, and the second end of the secondary side is connected with the phase line and the zero line of the charging system.

11. The charging system according to claim 10, wherein the power supply device includes:

The output end of the fourth filter is connected with the primary side of the first transformer, and the input end of the third low-pass filter is connected with a fourth inductor and a fifth inductor which are included in the auxiliary switching tube module;

and the fourth switch is connected with the two input ports of the third low-pass filter in parallel, and the fourth switch is arranged between the two input ends of the auxiliary switching tube module.

12. The charging system according to any one of claims 1-9, further comprising:

The charging system comprises a plurality of first switches, wherein the first switches are respectively arranged on a plurality of phase lines and zero lines of the charging system;

the fourth capacitors are arranged between the target phase line and the zero line, and one end of each fourth capacitor connected with the zero line is also connected with the active leakage current suppression circuit.

13. The charging system according to any one of claims 1-9, further comprising:

And the common mode inductance module is connected between the power grid and the switching tube module and is arranged on a phase line of the charging system.

14. The charging system according to any one of claims 1-9, wherein the switching tube module employs a symmetrical switching control strategy.

15. An energy storage system, comprising:

An energy storage device;

a charging system according to any one of claims 1 to 14, said charging system being connected between an electrical grid and said energy storage device.

16. A vehicle, characterized by comprising:

The energy storage system of claim 15.