WO2017148408A1

WO2017148408A1 - Energy storage charging system

Info

Publication number: WO2017148408A1
Application number: PCT/CN2017/075424
Authority: WO
Inventors: 华桂潮
Original assignee: 英飞特电子（杭州）股份有限公司
Priority date: 2016-03-02
Filing date: 2017-03-02
Publication date: 2017-09-08

Abstract

Provided is an energy storage charging system, provided with a centralised direct current bus to supply electricity, the power of the direct current bus being provided by an AC-DC module, the direct current bus being cross-connected to an energy storage unit, the input of one or a plurality of DC-DC charging modules being taken from the direct current bus. When the output power of the AC-DC module is not sufficient, the energy storage unit provides energy to the DC-DC charging modules, and has a load shifting effect, thereby reducing the total power of AC-DC conversion, and overcoming the problem of power grid electricity supply capacity bottlenecks in the development of new energy vehicle charging stations. In addition, the direct current bus supplies electricity in a centralised manner, thus enabling the DC-DC charging modules to satisfy diverse charging requirements of different types of new energy vehicles at a low cost, thereby reducing the total cost of the charging system.

Description

Energy storage charging system

This application claims the priority of the Chinese Patent Application filed on March 2, 2016, the Chinese Patent Office, the application number is 201610118208.2, and the invention name is “an energy storage charging system”, and submitted to China on March 2, 2016. The Patent Office, the application No. 201620161172.1, the priority of the utility model is the benefit of the disclosure of the entire disclosure of the entire disclosure of the entire disclosure of

Technical field

Embodiments of the present application relate to a charging system for a new energy vehicle, and more particularly to a charging system having a peak-cutting valley energy storage unit.

Background technique

With the development of new energy vehicles, especially the popularity of electric vehicles, the demand for fast charging stations is growing. It is widely expected that electric vehicles will have long battery life and short charging time, which means that the speed of the fast charging machine will be larger and larger, and the load capacity of the power grid is limited. Especially the maximum capacity of the power grid in the urban center is basically fixed, it is difficult to charge. The need for stations has increased the amount of electricity used, while the demand for charging stations in densely populated areas is greater, so the load on the grid becomes a key bottleneck in the construction of charging stations. The traditional charging stations are mostly composed of independent AC-DC chargers. As shown in Figure 1, the traditional charging station has a large peak power demand, but the average usage rate is low, that is, the average power is low, and the usage rate of many charging stations. Even 10% of the time is not available, but the configuration of the grid capacity must take into account the simultaneous use of the charger used, that is, according to the sum of the maximum power of all the chargers, which causes a huge waste of grid capacity, or grid capacity. Unable to meet the construction needs of charging stations, and promote the formation of charging stations in a large scale Obstructed.

Summary of the invention

The embodiment of the present application provides an energy storage charging system to solve the problem that the existing independent AC-DC charger has low utilization rate but large peak power and high requirements on grid capacity configuration.

The technical solution provided by the embodiment of the present application is as follows:

An energy storage charging system, comprising an AC-DC module, one or more DC-DC charging modules, an energy storage unit, a DC bus and a control module, wherein

An output of the AC-DC module is connected to the DC bus, and the DC bus is used to provide electric power for all DC-DC charging modules;

An input end of the DC-DC charging module is connected to the DC bus, and an output end thereof is used for connecting an electric vehicle;

The energy storage unit is connected to the DC bus, charged by the AC-DC module, and supplies power to the DC-DC charging module when the output power of the AC-DC module is insufficient;

The control module controls charging or discharging of the energy storage unit by controlling power of the AC-DC module and the DC-DC charging module supplied to each channel.

Optionally, the output end of the AC-DC module includes a positive end and a negative end, the positive end is connected to the DC bus, and the negative end is used as a ground end. The input end of the DC-DC charging module is two ends, and one end is connected. The DC bus is connected to the ground end, and the DC bus and the ground end are respectively connected to two ends of the energy storage unit.

Optionally, when the DC-DC charging module is multiplexed, a sum of maximum output powers of all the DC-DC charging modules is greater than a maximum output power of the AC-DC module.

Optionally, the maximum output power of the AC-DC module is configured according to the actual normal used charging power of the DC-DC charging module.

Optionally, when the total charging requirement of the DC-DC charging module is greater than the maximum output power of the AC-DC module, and the power of the energy storage unit is insufficient to discharge, the control module allocates according to a preset algorithm. The charging power of the DC-DC charging module is not greater than the maximum output power of the AC-DC module.

Optionally, the control module adjusts the charging priority level according to the amount of remaining power of the car or the charging price.

Optionally, when the DC-DC charging module is multiplexed, a sum of maximum output powers of all the DC-DC charging modules is equal to a maximum output power of the AC-DC module.

Optionally, when the energy storage unit is charged, the AC-DC module operating state is in a steady current control state, and the steady current control state stabilizes the charging current of the energy storage unit.

Optionally, when the energy storage unit is charged, a control loop in the AC-DC module samples a charging current of the energy storage unit, and according to the charging current and a required condition of the DC-DC charging module The total power obtains a steady current value of the charging current, and the charging current is stabilized by a closed loop adjustment control.

Optionally, when the energy storage unit is discharged, the AC-DC module operates in a maximum current limiting state, and the maximum current limiting state causes an output current of the AC-DC module to be a maximum current value.

Optionally, when the energy storage unit is in a floating state or a disengaged state, the AC-DC module operates in a steady state.

Optionally, a minimum discharge voltage of the energy storage unit is higher than a maximum output voltage of the DC-DC charging module, and the DC-DC charging module is implemented by a BUCK step-down circuit.

Optionally, the control module includes:

Connecting to the receiving end of the control module, for receiving charging by the DC-DC charging module a receiving unit of a demand signal;

Determining, according to the charging demand signal, a first determining unit that determines whether an output power of the AC-DC module is greater than a total required power of the DC-DC charging module;

a detecting unit that detects a quantity of the energy storage unit and outputs a detection signal;

If the determination result of the first determining unit is yes, determining, according to the detection signal, whether the energy storage unit needs to be charged;

If the determination result of the first determining unit is no, determining, according to the detection signal, whether the energy storage unit has a third determining unit of remaining power;

If the determination result of the second determining unit is yes, controlling the AC-DC module to operate in a steady current control state, to stabilize the charging current of the energy storage unit, and if the third determining unit determines the result If so, the first control unit that controls the AC-DC module to operate in a maximum current limiting state to cause the output current of the AC-DC module to be the maximum current value.

Optionally, the maximum current value is a preset value of the AC-DC module, or the maximum current value is a value set according to a power consumption limit of the power grid.

Optionally, determining, according to the detection signal, whether the energy storage unit needs to be charged, and the basis includes one or more of the following: an energy quantity of the energy storage unit, a power consumption limit of the power grid, and an artificially set instruction.

Optionally, the control module further includes: if the determination result of the second determining unit is no, controlling the second control unit in which the AC-DC module operates in a steady state.

Optionally, the control module further includes: if the determination result of the third determining unit is no, the third control unit that controls the power of the DC-DC charging module according to a preset algorithm.

Optionally, the control method of the control module is:

Step 1: Receive a charging demand signal from the DC-DC charging module;

Step 2: Determine whether the output power of the AC-DC module is greater than the total required power of the DC-DC charging module according to the charging demand signal. If the determination result is yes, proceed to step 4; if the determination result is no Go to step 5;

Step 3: detecting the power of the energy storage unit and outputting a detection signal;

Step 4: determining, according to the detection signal, whether the energy storage unit needs to be charged;

Step 5: determining, according to the detection signal, whether the energy storage unit has a remaining power;

Step 6: If the result of the determination in step 4 is YES, control the AC-DC module to operate in a steady current control state, so that the charging current of the energy storage unit is stabilized;

Step 7: If the result of the determination in the step 5 is YES, the AC-DC module is controlled to operate in a maximum current limiting state, so that the output current of the AC-DC module is the maximum current value.

Optionally, the control method further includes:

Step 8: If the result of the determination in step 4 is no, the AC-DC module is controlled to operate in a regulated state.

Optionally, the control method further includes:

Step 9: If the result of the determination in step 5 is no, the power of the DC-DC charging module is controlled according to a preset algorithm.

Optionally, the AC-DC module and the DC-DC charging module are respectively disposed in different spaces.

Optionally, the multiple DC-DC charging modules are separately packaged modules.

The embodiment of the present application provides an energy storage charging system with centralized DC bus power supply, wherein the power of the DC bus is provided by an AC-DC module, and the DC bus crosses the energy storage unit, all the way or The input of the multi-channel DC-DC charging module is taken from the DC bus. When the output power of the AC-DC module is insufficient, the energy storage unit provides energy to the DC-DC charging module, functions as a peak-shaping, and reduces the total power of the AC-DC conversion, thereby overcoming The power supply capacity bottleneck problem developed by the new energy vehicle charging station; at the same time, due to the centralized power supply of the DC bus, the DC-DC charging module can meet the diversified charging requirements of different types of new energy vehicles at a low cost, and reduce the charging. The overall cost of the system.

DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings to be used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present application, and other drawings can be obtained according to the drawings without any creative work for those skilled in the art.

1 is a schematic diagram of a charging system in the prior art;

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

3 is a schematic diagram of an embodiment of a control module provided by an embodiment of the present application;

4 is a schematic diagram of another embodiment of a control module provided by an embodiment of the present application;

FIG. 5 is a schematic diagram of another embodiment of a control module provided by an embodiment of the present application; FIG.

FIG. 6 is a flowchart of an embodiment of a control method of a control module according to an embodiment of the present application.

detailed description

The above described objects, features and advantages of the embodiments of the present application will become more apparent and understood.

Specifically, the charging system is as shown in FIG. 2, and includes: an AC-DC module 100, a one-way or multiple-channel DC-DC charging module 200, a control module 300, a DC bus 400, and an energy storage unit 500.

The output of the AC-DC module 100 is connected to the DC bus 400, and the DC bus 400 is used to provide electric power for all DC-DC charging modules 200;

An input end of the DC-DC charging module 200 is connected to the DC bus 400, and an output end of the DC-DC charging module 200 is used to connect an electric vehicle;

The energy storage unit 500 is connected to the DC bus 400, and the AC-DC module 100 charges the energy storage unit 500. When the output power of the AC-DC module 100 is insufficient, the DC is the DC. - DC charging module 200 is powered;

The control module 300 controls charging or discharging of the energy storage unit 500 by controlling the power of the AC-DC module 100 and the DC-DC charging module 200 supplied to each channel.

It should be noted that the output end of the AC-DC module 100 is two ends, the positive end is connected to the DC bus 400, the negative end is used as the reference potential end, that is, the “ground end”, and the input end of the DC-DC charging module is two. One end is connected to the DC bus 400 at one end, and the other end is connected to the ground end, and the DC bus 400 and the ground end are respectively connected to both ends of the energy storage unit 500.

It should be noted that the energy storage unit 500 in the embodiment of the present application may be any device or circuit that stores electric power, such as an energy storage battery, a storage capacitor, and the like.

When the energy storage unit 500 needs to be charged, the energy storage unit 500 is charged by the output power of the AC-DC module 100. When the energy storage unit 500 is discharged, it is connected to the energy storage unit 500. The DC bus 400 causes the energy storage unit 500 to provide energy to the DC-DC charging module 200.

The control module 300 controls the output power of the AC-DC module 100, the working state, and the like, controls the power allocation of each of the DC-DC charging modules 200 according to a preset algorithm, and controls the AC-DC module. 100 and the DC-DC charging module to control charging or discharging of the energy storage unit 500.

The embodiment of the present application provides an energy storage charging system with centralized DC bus power supply, wherein the power of the DC bus is provided by the AC-DC module 100, and the DC bus 400 is connected to the energy storage unit 500, one or more channels. The input of the DC-DC charging module 200 is taken from the DC bus 400. When the output power of the AC-DC module 100 is insufficient, the energy storage unit 500 provides energy to the DC-DC charging module to serve as a peak-shaping and valley-reducing function, and reduces the total power of the AC-DC conversion. Overcoming the bottleneck problem of the power supply capacity of the new energy vehicle charging station; at the same time, due to the centralized power supply of the DC bus, the DC-DC charging module can meet the diversified charging requirements of different types of new energy vehicles at a very low cost, and reduce The overall cost of the charging system.

In order to be compatible with different power charging requirements, the maximum output power of each charger is often much larger than the average power of charging. In fact, the probability that all chargers simultaneously charge a large-capacity battery car is very small. Even if the large-capacity car is charged at the same time, it is difficult to be in the maximum power state at the same time, which causes the actual normal use power of the charger to be much lower than the sum of the power of the charger, and the utilization rate is very low. In the charging system of the present application, all the charging modules share a centralized AC-DC module, and the power of the centralized AC-DC module can be configured according to the charging power that is actually used normally, thereby avoiding the charging device in the charging station in the prior art. The cost is low due to low utilization, and the DC-DC charging module can be a low-cost small-volume non-isolated module; and the energy storage unit is in the When the output power of the AC-DC module is insufficient, energy is supplied to the DC-DC charging module, which further optimizes the configuration of the grid capacity.

At the same time, the existing charger is a separate AC-DC charger, as shown in Figure 1. Each charger is set to a large volume, occupying a considerable space in the charging parking space of the electric vehicle. In the charging system provided by the present application, the AC-DC module 100 as a high-power power supply and the DC-DC charging module 200 can be respectively disposed in different spaces. Therefore, the AC-DC module 100 does not have to be disposed in an electric vehicle. The charging location can be set in a remote or remote area, and only a small volume of the DC-DC charging module is placed near the parking space, which greatly reduces the footprint of the electric vehicle parking space.

Optionally, the multiple DC-DC charging modules 200 are separately packaged modules.

Since each DC-DC charging module 200 is respectively connected to a different electric vehicle to charge different electric vehicles, when each of the DC-DC charging modules 200 is separately packaged, and the cost thereof is low and small, further Reduce the footprint of the charger in the charging parking space. In an actual application, the AC-DC module 100 may be disposed in a different space from the DC-DC charging module 200, so that the space of the electric vehicle charging place is rationally utilized.

Optionally, when the DC-DC charging module is multiplexed, a sum of maximum output powers of all the DC-DC charging modules 200 is greater than or equal to a maximum output power of the AC-DC module 100.

When the DC-DC charging module is multiplexed, the probability that all DC-DC charging modules 200 simultaneously output the maximum power is extremely small, and at the same time, all DC-DC charging modules 200 simultaneously output the maximum power to the distribution network instantaneously. The power demand is too high, and therefore, when designing the maximum output power of the AC-DC module 100, it can be less than the sum of the maximum powers output by all of the DC-DC charging modules 200. example For example, a total of 10 DC-DC charging modules, each DC-DC charging module has a maximum output power of 50 kW, and the maximum output power of the AC-DC module 100 may be less than 500 kW. This is because the probability that all DC-DC charging modules need to output 50kw at the same time is very low. Therefore, the AC-DC module 100 does not need to be designed as a module of 500kw, so that the charging system of the present application can effectively reduce AC- The cost and volume of the DC module 100 are also compatible with the charging power of different electric vehicles. For occasional DC-DC charging module total power demand is greater than the maximum output power of the AC-DC module, and the energy storage battery is also exhausted, the control module can allocate and limit the DC-DC charging module according to a preset algorithm. The power is adjusted, for example, according to the amount of remaining power of the car or the charging price.

Optionally, referring to FIG. 3, the control module 300 includes: a receiving unit 301, a detecting unit 302, a first determining unit 303, a second determining unit 304, a third determining unit 305, and a first control unit 306.

The receiving unit 301 is connected to the receiving end of the control module 300 for receiving the charging demand signal sent by the DC-DC charging module 200;

The first determining unit 303 determines, according to the charging demand signal, whether the output power of the AC-DC module 100 is greater than the total required power of all the DC-DC charging modules;

The detecting unit 302 detects the power of the energy storage unit 500 and outputs a detection signal;

If the determination result of the first determining unit 303 is YES, the second determining unit 304 determines, according to the detection signal, whether the energy storage unit 500 needs to be charged;

If the determination result of the first determining unit 303 is negative, the third determining unit 305 determines whether the energy storage unit 500 has a remaining power according to the detection signal;

If the determination result of the second determining unit 304 is YES, the first control unit 306 controls the The AC-DC module 100 operates in a steady current control state to stabilize the charging current of the energy storage unit 500. If the determination result of the third determining unit 305 is yes, the first control unit 306 controls the AC-DC. The module 100 operates in a maximum current limiting state such that the output current of the AC-DC module 100 is the maximum current value.

"According to the detection signal, it is determined whether the energy storage unit 500 needs to be charged", which may be based on one or more of the power storage unit power, the grid power limit, the artificially set command, and the like.

When the energy storage unit 500 is charged, the AC-DC module 100 is in a steady current control state, and the steady current control state stabilizes the charging current of the energy storage unit 100.

When the energy storage unit 500 is charged, it is charged by the AC-DC module 100. In addition to charging the energy storage unit 500, the AC-DC module 100 output power needs to supply power to the DC-DC charging module. Since the charging current of the energy storage unit needs to be controlled, the control loop in the AC-DC module samples the charging current of the energy storage unit 500, and according to the charging current and the DC-DC charging module The total power is obtained as a steady current value of the charging current, and the charging current is stabilized by a closed-loop regulation control.

When the energy storage unit 500 is discharged, the AC-DC module 100 operates in a maximum current limiting state that causes the output current of the AC-DC module 100 to be a maximum current value.

When the energy storage unit 500 is discharged, the energy of the energy storage unit 500 is supplied to the DC-DC charging module through a DC bus. At this time, the output power that the AC-DC module 100 can provide is insufficient to meet the The total power required by the DC-DC charging module, the AC-DC module 100 will operate in a maximum current limiting state, providing the DC-DC charging module power in a maximum output current. The power provided by the AC-DC module 100 is removed, and the remaining power required by the DC-DC charging module is provided by the energy storage unit 500.

When the AC-DC module 100 operates in the maximum current limiting state, the output current value is a maximum current value, which may be a preset value set by the AC-DC itself, that is, an output of the AC-DC module. The current cannot exceed the preset value; it may also be a value set according to the power limitation of the power grid, that is, the AC-DC module receives the power limit signal of the power grid, and the corresponding value set according to the signal.

Optionally, referring to FIG. 4, the control module 300 further includes: if the determination result of the second determining unit 304 is negative, controlling the second control unit 307 that the AC-DC module 100 operates in a steady state .

Optionally, when the energy storage unit 500 is in a floating state or a disengaged state, the AC-DC module 100 operates in a regulated state.

After the energy storage unit 500 is fully charged, the AC-DC module 100 operates in a steady state, and the output voltage of the AC-DC module 100 is stabilized at a value slightly higher than the energy storage unit 500. The terminal voltage, at this time, the energy storage unit 500 is in a floating state, that is, the charging is satisfied with a small current. Or when the energy storage unit 500 is not connected to the DC bus 400, that is, the disengaged state, such as The device such as a switch is disconnected from the DC bus 400. At this time, the AC-DC module 100 operates in a regulated state. When the AC-DC module 100 operates in a regulated state, its energy is supplied to the DC-DC charging module.

Optionally, referring to FIG. 5, the control module 300 further includes: if the determination result of the third determining unit 304 is negative, controlling the third control of the power of the DC-DC charging module according to a preset algorithm. Unit 308.

It should be noted that, when the total charging requirement of the DC-DC charging module is greater than the maximum output power of the AC-DC module, and the power of the energy storage unit is insufficient to be discharged, the control module 300 is configured according to a preset algorithm. The charging power of the DC-DC charging module is not greater than the maximum output power of the AC-DC module 100 to avoid over-discharging of the energy storage unit.

Optionally, the minimum discharge voltage of the energy storage unit 500 is higher than the maximum output voltage of the DC-DC charging module, and the DC-DC charging module is implemented by a BUCK step-down circuit.

Optionally, the control module 300 in the charging system of the present application, and the control method thereof, refer to FIG. 6, including:

Step 1: receiving the DC-DC charging module 200 to issue a charging demand signal;

Step 3: detecting the power of the energy storage unit 500 and outputting a detection signal;

Step 4: determining, according to the detection signal, whether the energy storage unit 500 needs to be charged;

Step 5: determining, according to the detection signal, whether the energy storage unit 500 has a remaining power;

It should be noted that Step 1 and Step 2 and Step 3 may be performed in parallel, and the order of the steps is not limited, that is, in addition to the above manner, the steps of the equivalent control method are: Step 3, Step 1, Step 2, Step 4. Step 5, Step 6, Step 7.

Optionally, the control method further includes:

Step 8: If the result of the determination of 4 is no, the AC-DC module is controlled to operate in a regulated state.

Optionally, the control method further includes:

Optionally, the AC-DC module 100 is an isolation module, that is, the AC-DC module 100 is implemented by an isolation circuit; and the DC-DC charging module 200 is implemented by a non-isolated circuit.

Optionally, the AC-DC module 100 is a non-isolated module, that is, the AC-DC module 100 is implemented by a non-isolated circuit; the DC-DC charging module 200 is an isolated charging module, that is, the DC-DC. The charging module 200 is implemented by an isolation circuit.

The above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the application. Although the present application has been disclosed above in the preferred embodiments, it is not intended to limit the application. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present application by using the methods and technical contents disclosed above, or modify the equivalents of equivalent changes without departing from the scope of the technical solutions of the present application. Example. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments in accordance with the technical spirit of the present application are still within the scope of the technical solutions of the present application.

Claims

An energy storage charging system, comprising: an AC-DC module, one or more DC-DC charging modules, an energy storage unit, a DC bus and a control module, wherein

An output of the AC-DC module is connected to the DC bus, and the DC bus is used to provide electric power for all DC-DC charging modules;

An input end of the DC-DC charging module is connected to the DC bus, and an output end thereof is used for connecting an electric vehicle;

The energy storage unit is connected to the DC bus, charged by the AC-DC module, and supplies power to the DC-DC charging module when the output power of the AC-DC module is insufficient;

The control module controls charging or discharging of the energy storage unit by controlling power of the AC-DC module and the DC-DC charging module supplied to each channel.
The charging system according to claim 1, wherein the output end of the AC-DC module comprises a positive terminal and a negative terminal, the positive terminal is connected to the DC bus, and the negative terminal is used as a ground terminal, and the DC-DC charging is performed. The input ends of the module are two ends, one end is connected to the DC bus, and the other end is connected to the ground end, and the DC bus and the ground end are respectively connected to both ends of the energy storage unit.
The charging system according to claim 1, wherein when the DC-DC charging module is multiplexed, a sum of maximum output powers of all of the DC-DC charging modules is greater than a maximum of the AC-DC module Output Power.
The charging system according to claim 3, wherein the maximum output power of the AC-DC module is configured in accordance with the actual normal used charging power of the DC-DC charging module.
The charging system according to claim 1, wherein when the total charging demand of the DC-DC charging module is greater than the maximum output power of the AC-DC module, and the energy of the energy storage unit is not When sufficient to discharge, the control module allocates the charging power of the DC-DC charging module to be no greater than the maximum output power of the AC-DC module according to a preset algorithm.
The charging system according to claim 5, wherein the control module adjusts the charging priority level according to the amount of remaining power of the car or the charging price.
The charging system according to claim 1, wherein when the DC-DC charging module is multiplexed, a sum of maximum output powers of all of the DC-DC charging modules is equal to a maximum of the AC-DC module Output Power.
The charging system according to claim 1, wherein when the energy storage unit is charged, the AC-DC module operating state is in a steady current control state, and the steady current control state causes the energy storage unit to be charged. The current is steady.
The charging system according to claim 8, wherein when the energy storage unit is charged, a control loop in the AC-DC module samples a charging current of the energy storage unit, and according to the charging current The total power required by the DC-DC charging module obtains a steady current value of the charging current, and the charging current is stabilized by closed loop adjustment control.
The charging system according to claim 1, wherein said AC-DC module operates in a maximum current limiting state when said energy storage unit is discharged, said maximum current limiting state of said AC-DC module The output current is the maximum current value.
The charging system according to claim 1, wherein said AC-DC module operates in a regulated state when said energy storage unit is in a floating state or a disengaged state.
The charging system according to claim 1, wherein a minimum discharge voltage of the energy storage unit is higher than a maximum output voltage of the DC-DC charging module, and the DC-DC charging module is implemented by a BUCK step-down circuit. .
The charging system of claim 1 wherein said control module comprises:

a receiving end of the control module, configured to receive a charging demand signal sent by the DC-DC charging module;

Determining, according to the charging demand signal, a first determining unit that determines whether an output power of the AC-DC module is greater than a total required power of the DC-DC charging module;

a detecting unit that detects a quantity of the energy storage unit and outputs a detection signal;

If the determination result of the first determining unit is yes, determining, according to the detection signal, whether the energy storage unit needs to be charged;

If the determination result of the first determining unit is no, determining, according to the detection signal, whether the energy storage unit has a third determining unit of remaining power;

If the determination result of the second determining unit is yes, controlling the AC-DC module to operate in a steady current control state, to stabilize the charging current of the energy storage unit, and if the third determining unit determines the result If so, the first control unit that controls the AC-DC module to operate in a maximum current limiting state to cause the output current of the AC-DC module to be the maximum current value.
The charging system according to claim 13, wherein said maximum current value is a preset value of said AC-DC module, or said maximum current value is a value set according to a grid power consumption limit.
The charging system according to claim 13, wherein determining whether the energy storage unit needs to be charged according to the detection signal is based on one or more of the following: a power quantity of the energy storage unit, a power consumption limit of the power grid, And instructions for human settings.
The charging system according to claim 13, wherein the control module further comprises: if the determination result of the second determining unit is negative, controlling the AC-DC module to operate stably a second control unit in a pressurized state.
The charging system according to claim 13, wherein the control module further comprises: if the determination result of the third determining unit is negative, controlling the power of the DC-DC charging module according to a preset algorithm The third control unit.
The charging system according to claim 1, wherein the control method of the control module is:

Step 1: Receive a charging demand signal from the DC-DC charging module;

Step 2: Determine whether the output power of the AC-DC module is greater than the total required power of the DC-DC charging module according to the charging demand signal. If the determination result is yes, proceed to step 4; if the determination result is no Go to step 5;

Step 3: detecting the power of the energy storage unit and outputting a detection signal;

Step 4: determining, according to the detection signal, whether the energy storage unit needs to be charged;

Step 5: determining, according to the detection signal, whether the energy storage unit has a remaining power;

Step 6: If the result of the determination in step 4 is YES, control the AC-DC module to operate in a steady current control state, so that the charging current of the energy storage unit is stabilized;

Step 7: If the result of the determination in the step 5 is YES, the AC-DC module is controlled to operate in a maximum current limiting state, so that the output current of the AC-DC module is the maximum current value.
The charging system according to claim 18, wherein said maximum current value is a preset value of said AC-DC module, or said maximum current value is a value set according to a grid power consumption limit.
The charging system according to claim 18, wherein the control method further comprises:

Step 8: If the result of the determination in step 4 is no, the AC-DC module is controlled to operate in a regulated state.
The charging system according to claim 18, wherein the control method further comprises:

Step 9: If the result of the determination in step 5 is no, the power of the DC-DC charging module is controlled according to a preset algorithm.
The charging system according to claim 1, wherein the AC-DC module and the DC-DC charging module are respectively disposed in different spaces.
The charging system according to claim 1, wherein the plurality of DC-DC charging modules are separately packaged modules.