A DC coupled optical storage and charging system and control method thereof

Abstract

A DC-coupled photovoltaic storage and charging system and a control method thereof, comprising a battery cabinet and a power cabinet; the battery cabinet is provided with a plurality of battery packs PACK, the battery packs PACK are connected to one end of a high-voltage box, and the other end of the high-voltage box is connected to a power supply bus; the power cabinet is provided with an AC input terminal, and the AC input terminal is connected to the power supply bus through an AC / DC conversion module; it also comprises at least two groups of photovoltaic input terminals, and the photovoltaic input terminals are connected to the power supply bus through an MPPT module; the power supply bus is also connected to a relay-type PDU module through a DC / DC conversion module, and the output terminal of the relay-type PDU module is used to supply energy to a plurality of charging guns.

Description

Technical Field

[0001] The present invention relates to the field of electric vehicle charging, and in particular to a direct current coupled light storage and charging system and a control method thereof. Background Art

[0002] Such charging station systems in the prior art often still use a single photovoltaic system, have no complementary power supply, cannot operate off-grid or in an isolated island, cannot operate at high power, cannot flexibly distribute power, and have few applications in V2G mode. Summary of the invention

[0003] In order to solve the above problems, the present technical solution provides a DC-coupled photovoltaic storage and charging system and a control method thereof.

[0004] To achieve the above purpose, the technical solution is as follows:

[0005] A DC coupled light storage and charging system, comprising a battery cabinet and a power cabinet;

[0006] The battery cabinet is provided with a plurality of battery packs PACK, the battery pack PACK is connected to one end of the high-voltage box, and the other end of the high-voltage box is connected to the power supply bus;

[0007] The power cabinet is provided with an AC input terminal, and the AC input terminal is connected to the power supply bus through an AC / DC conversion module;

[0008] It also includes at least two groups of photovoltaic input terminals, and the photovoltaic input terminals are connected to the power supply busbar through the MPPT module;

[0009] The power supply bus is also connected to the relay-type PDU module through a DC / DC conversion module, and the output end of the relay-type PDU module is used to supply energy to multiple charging guns.

[0010] In some embodiments, the AC / DC conversion modules are provided in plurality and are arranged in parallel, and the MPPT modules are also provided in plurality and are arranged in parallel.

[0011] In some embodiments, the DC / DC conversion module is provided in plurality and is arranged in parallel.

[0012] In some embodiments, the relay-type PDU module is provided with a plurality of PW modules, and each of the PW modules corresponds to a DC contactor KM.

[0013] In some embodiments, a switch QF connected to the battery pack PACK is provided in the high voltage box, a switch QF1 is connected to the AC input end, and a switch QF2 is connected to the photovoltaic input end.

[0014] In some embodiments, the power supply bus is also connected to the fan via an AC / DC conversion module.

[0015] The present application also provides a control method, based on the above-mentioned DC-coupled photovoltaic storage and charging system, further comprising the following steps:

[0016] When super charging gun 1 is working, the power of PW2~20 modules can be allocated for use. At this time, the power can be freely and flexibly allocated through the ports 1~19 of the relay PDU board. The DC contactor KM1 of any layer of the relay PDU board is closed, and KM2~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards;

[0017] When super charging gun 16 is working, the power of PW1~15 and 17~20 modules can be allocated for use. At this time, the power can be freely and flexibly allocated through the ports 1~19 of the relay PDU board. The DC contactor KM16 of any layer of relay PDU board is closed, and KM1~15 and 17~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards.

[0018] When fast charging gun 2 is working and super charging guns 1 and 16 are not working, the power of PW1, 3~20 modules can be deployed for use. At this time, the relay PDU board 1~19 ports are freely and flexibly deployed. The DC contactor KM2 of any layer of relay PDU board is closed, and KM1, 3~20 are closed. The use of other fast charging guns requires the full flexible deployment of power through the relay PDU boards on the remaining layers;

[0019] When super charging guns 1 and 16 are working, the power of modules other than PW1 and PW16 can be allocated. At this time, the power can be freely and flexibly allocated through ports 1 to 19 of the relay PDU board. The DC contactor KM2 of any layer of the relay PDU board is closed, and KM1, 3 to 15, and 17 to 20 are closed. The use of other fast charging guns requires the full and flexible allocation of power through the relay PDU boards on the remaining layers.

[0020] The beneficial effects of this application are:

[0021] The electric vehicle bidirectional charging module of this application obtains power from the DC bus, and flexibly allocates power through the onboard relay PDU module matrix. It supports 2 super charging guns and 14 fast charging guns, greatly improves the charging efficiency, and is very convenient to charge. It can be configured with 1 to 20 electric vehicle bidirectional charging modules, with a maximum output of 800kW. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0023] Figure 1 The structure of the embodiment of the present invention is shown in FIG. Figure 1 ;

[0024] Figure 2 The structure of the embodiment of the present invention is shown in FIG. Figure 2 ;

[0025] Figure 3 is a schematic diagram of a charging module matrix according to an embodiment of the present invention;

[0026] Figure 4 is a schematic diagram of a board-mounted relay PDU board according to an embodiment of the present invention;

[0027] Figure 5 It is a schematic diagram of a relay-type PDU module matrix and a 1-N matrix according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] Please refer to Figure 1-4 As shown, a DC-coupled solar storage and charging system includes a battery cabinet and a power cabinet;

[0030] The battery cabinet is provided with a plurality of battery packs PACK, the battery pack PACK is connected to one end of the high-voltage box, and the other end of the high-voltage box is connected to the power supply bus;

[0031] The power cabinet is provided with an AC input terminal, and the AC input terminal is connected to the power supply bus through an AC / DC conversion module;

[0032] It also includes at least two groups of photovoltaic input terminals, and the photovoltaic input terminals are connected to the power supply busbar through the MPPT module;

[0033] The power supply bus is also connected to the relay-type PDU module through a DC / DC conversion module, and the output end of the relay-type PDU module is used to supply energy to multiple charging guns.

[0034] In this embodiment, a plurality of the AC / DC conversion modules are provided and are arranged in parallel, and a plurality of the MPPT modules are also provided and are arranged in parallel.

[0035] In this embodiment, a plurality of DC / DC conversion modules are provided and are connected in parallel.

[0036] In this embodiment, the relay-type PDU module is provided with a plurality of PW modules, and each of the PW modules corresponds to a DC contactor KM.

[0037] In this embodiment, a switch QF connected to the battery pack PACK is provided in the high voltage box, a switch QF1 is connected to the AC input end, and a switch QF2 is connected to the photovoltaic input end.

[0038] In this embodiment, the power supply bus is also connected to the fan via an AC / DC conversion module.

[0039] The present application also provides a control method, based on the above-mentioned DC-coupled photovoltaic storage and charging system, further comprising the following steps:

[0040] When super charging gun 1 is working, the power of PW2~20 modules can be allocated for use. At this time, the power can be freely and flexibly allocated through the ports 1~19 of the relay PDU board. The DC contactor KM1 of any layer of the relay PDU board is closed, and KM2~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards;

[0041] When super charging gun 16 is working, the power of PW1~15 and 17~20 modules can be allocated for use. At this time, the power can be freely and flexibly allocated through the ports 1~19 of the relay PDU board. The DC contactor KM16 of any layer of relay PDU board is closed, and KM1~15 and 17~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards.

[0042] When fast charging gun 2 is working and super charging guns 1 and 16 are not working, the power of PW1, 3~20 modules can be deployed for use. At this time, the relay PDU board 1~19 ports are freely and flexibly deployed. The DC contactor KM2 of any layer of relay PDU board is closed, and KM1, 3~20 are closed. The use of other fast charging guns requires the full flexible deployment of power through the relay PDU boards on the remaining layers;

[0043] When super charging guns 1 and 16 are working, the power of modules other than PW1 and PW16 can be allocated. At this time, the power can be freely and flexibly allocated through ports 1 to 19 of the relay PDU board. The DC contactor KM2 of any layer of the relay PDU board is closed, and KM1, 3 to 15, and 17 to 20 are closed. The use of other fast charging guns requires the full and flexible allocation of power through the relay PDU boards on the remaining layers.

[0044] See Figure 1 The DC-coupled solar storage and charging system includes a storage battery system, a photovoltaic system, a photovoltaic MPPT module, a power grid system, an energy storage inverter, a charging module DC / DC, an onboard relay PDU module and a charging gun.

[0045] The energy storage battery system includes multiple battery modules PACK and high-voltage boxes, which are connected to the DC bus through power cables;

[0046] The photovoltaic panels are connected to the DC bus through the photovoltaic power generation DC / DC unidirectional conversion MPPT module. 1 to 4 MPPT modules can be configured, which can support up to 4 MPPT controls and a maximum power of 200kW.

[0047] The grid is connected to the DC bus through the control switch QF1 and the energy storage converter AC / DC. 1 to 5 AC / DC modules can be configured, and the maximum power input can be 600kW.

[0048] The electric vehicle bidirectional charging module obtains power from the DC bus and flexibly allocates power through the onboard relay PDU module matrix. It supports 2 super charging guns and 14 fast charging guns, greatly improving the charging efficiency and making charging convenient. It can be configured with 1 to 20 electric vehicle bidirectional charging modules with a maximum output of 800kW.

[0049] The onboard relay PDU module matrix includes 19 layers of onboard relay PDU boards. Each PDU board supports 20 inputs and 20 outputs. The charging guns between each layer of boards are connected by copper busbars. It supports a maximum of 20 charging guns, of which 1 gun and 16 guns are designed as super charging guns with a maximum design current of 600A, and the rest are fast charging guns with a maximum current of 250A.

[0050] Onboard relay PDU board (see Figure 3 ) Working principle:

[0051] When super charging gun 1 is working, the power of PW2~20 modules can be allocated for use. At this time, the onboard relay PDU boards 1~19 are freely and flexibly allocated. The DC contactor KM1 of any layer of PDU board is closed, and KM2~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards (see Figure 4 ).

[0052] When super charging gun 16 is working, the power of PW1~15, 17~20 modules can be allocated for use. At this time, the onboard relay PDU boards 1~19 are freely and flexibly allocated. The DC contactor KM16 of any layer of PDU board is closed, and KM1~15, 17~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards (see Figure 4 ).

[0053] When fast charging gun 2 is working and super charging guns 1 and 16 are not working, the power of PW1, 3~20 modules can be deployed for use. At this time, the onboard relay PDU boards 1~19 are freely and flexibly deployed. The DC contactor KM2 of any layer of PDU board is closed, and KM1, 3~20 are closed. The use of other fast charging guns requires the full flexible deployment of power through the remaining layers of PDU boards (see Figure 4). When super charging guns 1 and 16 are working, the power of modules other than PW1 and PW16 can be allocated. At this time, the onboard relay PDU boards 1 to 19 can be freely and flexibly allocated. The DC contactor of KM2 on any layer of PDU board is closed, and KM1, 3 to 15, 17 to 20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards (see Figure 4 ).

[0054] In V2G mode, the onboard relay PDU board operates in the same way when electric vehicles sell electricity to the grid. When electric vehicles charge other electric vehicles, they allocate PW1-20 modules to output power to the DC bus according to their output power, and charge the other electric vehicles through the onboard relay PDU module matrix according to the location and required power of the other electric vehicles.

[0055] System operation mode:

[0056] 1. Maximum self-generation and self-use mode

[0057] In this working mode, when the photovoltaic array has sufficient energy, the photovoltaic energy will supply power to the electric vehicle, battery and grid in the order of charging the electric vehicle first, battery second and grid last. (When the local grid does not allow the inverter to access the grid, the power connected to the grid can be set to 0W). When the photovoltaic array has insufficient energy, the battery discharges to supply power to the electric vehicle. When the battery power supply is insufficient, the grid joins the power supply.

[0058] 2. Peak shaving and valley filling mode

[0059] At night, when electricity consumption is low, the bidirectional energy storage converter can convert AC power from the AC power grid into DC power and send it to the

[0060] Energy storage batteries and electric vehicle charging stations are charged.

[0061] During peak hours of electricity consumption during the day, when photovoltaic energy is insufficient, the energy storage battery system charges electric vehicles.

[0062] 3. V2G mode

[0063] In this working mode, electric vehicles can charge other electric vehicles through the electric vehicle bidirectional charging module and the onboard relay PDU module matrix, and can sell electricity to the power grid during peak power consumption.

[0064] System operation mode:

[0065] 1. Maximum self-generation and self-use mode

[0066] In this working mode, the power connected to the grid is set to 0W. When the output power of the photovoltaic array is 200kW, an electric car needs to be charged and requests 120kW. At this time, the photovoltaic energy charges the electric car with 120kW. The current battery system SOC is 50%, and the battery charges 80kW. The order of charging the electric car first, the battery second, and the grid last is met. (When the local grid does not allow the inverter to be connected to the grid, the power connected to the grid can be set to 0W).

[0067] When the output power of the photovoltaic array is 40kW, an electric car needs to be charged and requests 120kW. At this time, the photovoltaic energy charges the electric car with 40kW. The current battery system SOC is 90%, and the battery charges the electric car with 80kW.

[0068] When the output power of the photovoltaic array is 40kW, an electric car needs to be charged and requests 120kW. At this time, the photovoltaic energy charges the electric car with 40kW. The current battery system SOC is 40%, the battery charges the electric car with 40kW, and the power grid charges the electric car with 40kW.

[0069] 2. Peak shaving and valley filling mode

[0070] At night when electricity consumption is low, the energy storage battery charging time period is set to 2:00-6:00, and the energy storage battery SOC is 20%. The bidirectional energy storage inverter can convert AC power from the AC power grid into DC power, charging the energy storage battery with a power of 100kW, and the power grid also charges the electric vehicle.

[0071] During the peak electricity consumption in the daytime, the energy storage battery discharge time period is set to 12:00-14:00. When the photovoltaic energy is insufficient, the electric vehicle requests a power gap of 40KW. At this time, the energy storage battery system charges the electric vehicle with 40kW.

[0072] 3. V2G mode

[0073] In this working mode, an electric car is connected to the charging gun, the current SOC is 90%, and the available power is 215kWh. By setting it to the photovoltaic charging station power sales mode, the SOC is 20% and the power sales are stopped. At this time, an electric car requests to charge 50kW. The electric vehicle bidirectional charging module and the onboard relay PDU module matrix can output 50kW to the DC bus side, and then the electric vehicle bidirectional charging module and the onboard relay PDU module matrix can be used to allocate 50kW to the electric vehicle for charging, and the income is settled according to the power consumption.

[0074] If there is no electric vehicle requesting to charge at the moment and it is in the period of selling electricity to the grid, the electric vehicle can sell 50kW of electricity to the grid through the energy storage inverter and settle the income based on the amount of electricity consumed.

[0075] The onboard relay PDU module matrix includes 19 layers of onboard relay PDU boards. Each PDU board supports 20 inputs and 20 outputs. The charging guns between each layer of boards are connected by copper busbars. It supports a maximum of 20 charging guns, of which 1 gun and 16 guns are designed as super charging guns with a maximum design current of 600A, and the rest are fast charging guns with a maximum current of 250A.

[0076] Onboard relay PDU board (see Figure 3 ) Working principle:

[0077] When super charging gun 1 is working, the power of PW2~20 modules can be allocated for use. At this time, the onboard relay PDU boards 1~19 are freely and flexibly allocated. The DC contactor KM1 of any layer of PDU board is closed, and KM2~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards (see Figure 4 ).

[0078] When super charging gun 16 is working, the power of PW1~15, 17~20 modules can be allocated for use. At this time, the onboard relay PDU boards 1~19 are freely and flexibly allocated. The DC contactor KM16 of any layer of PDU board is closed, and KM1~15, 17~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards (see Figure 4 ).

[0079] When fast charging gun 2 is working and super charging guns 1 and 16 are not working, the power of PW1, 3~20 modules can be deployed for use. At this time, the onboard relay PDU boards 1~19 are freely and flexibly deployed. The DC contactor KM2 of any layer of PDU board is closed, and KM1, 3~20 are closed. The use of other fast charging guns requires the full flexible deployment of power through the remaining layers of PDU boards (see Figure 4 ). When super charging guns 1 and 16 are working, the power of modules other than PW1 and PW16 can be allocated. At this time, the onboard relay PDU boards 1 to 19 can be freely and flexibly allocated. The DC contactor of KM2 on any layer of PDU board is closed, and KM1, 3 to 15, 17 to 20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards (see Figure 4 ).

[0080] In V2G mode, the onboard relay PDU board operates in the same way when electric vehicles sell electricity to the grid. When electric vehicles charge other electric vehicles, they allocate PW1-20 modules to output power to the DC bus according to their output power, and charge the other electric vehicles through the onboard relay PDU module matrix according to the location and required power of the other electric vehicles.

[0081] See Figure 2, DC coupled wind and solar storage and charging system, and Figure 1 Compared with the DC-coupled photovoltaic storage and charging system, an alternative solution is added. By connecting the energy storage battery to the DC / DC module, different battery modules can be stepped up or down to establish a DC bus voltage. This solution can support the connection of multiple energy storage battery systems and improve the system's operating stability.

[0082] Wind power access has also been added. The wind turbine power generation is connected to the DC bus voltage through the wind turbine MPPT (AC / DC), which increases the energy input and is suitable for application in areas with developed wind power resources.

[0083] In the maximum self-generation and self-use mode, when the photovoltaic array energy and wind power energy are sufficient, the photovoltaic energy and wind power energy will supply power to the electric vehicle, battery and grid in the order of electric vehicle charging first, battery second and grid last. (When the local grid does not allow the inverter to access the grid, the power connected to the grid can be set to 0W). When the photovoltaic energy and wind power energy are insufficient, the battery discharges to supply power to the electric vehicle. When the battery power supply is insufficient, the grid joins the power supply.

[0084] See Figure 5 ,The onboard relay PDU module matrix 1-n can be optimized and designed according to the number of ,electrical vehicle bidirectional charging modules, and the number of access and ,other components of EVs can be adjusted accordingly to make the system compatible with different power ,requirements.

[0085] The above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application. Other principles and basic structures that are the same or similar to those of the present application are within the protection scope of the present application.

Claims

1. A DC coupled photovoltaic storage and charging system control method, characterized in that: Including battery cabinet and power cabinet; The battery cabinet is provided with a plurality of battery packs PACK, the battery pack PACK is connected to one end of the high-voltage box, and the other end of the high-voltage box is connected to the power supply bus; The power cabinet is provided with an AC input terminal, and the AC input terminal is connected to the power supply bus through an AC / DC conversion module; It also includes at least two groups of photovoltaic input terminals, and the photovoltaic input terminals are connected to the power supply busbar through the MPPT module; The power supply bus is also connected to the relay-type PDU module through a DC / DC conversion module, and the output end of the relay-type PDU module is used to supply energy to multiple charging guns; The AC / DC conversion modules are provided in plurality and are arranged in parallel, and the MPPT modules are also provided in plurality and are arranged in parallel; The DC / DC conversion modules are provided in plurality and are arranged in parallel; The relay-type PDU module is provided with a plurality of PW modules, and each of them has a DC contactor KM correspondingly; The high voltage box is provided with a switch QF connected to the battery pack PACK, the AC input end is connected to a switch QF1, and the photovoltaic input end is connected to a switch QF2; The power supply bus is also connected to the fan via an AC / DC conversion module; The following steps are also included: When super charging gun 1 is working, the power of PW2~20 modules can be allocated for use. At this time, the power can be freely and flexibly allocated through the ports 1~19 of the relay PDU board. The DC contactor KM1 of any layer of the relay PDU board is closed, and KM2~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards; When super charging gun 16 is working, the power of PW1~15 and 17~20 modules can be allocated for use. At this time, the power can be freely and flexibly allocated through the ports 1~19 of the relay PDU board. The DC contactor KM16 of any layer of relay PDU board is closed, and KM1~15 and 17~20 are closed. The use of other fast charging guns requires the full flexible allocation of power through the remaining layers of PDU boards. When fast charging gun 2 is working and super charging guns 1 and 16 are not working, the power of PW1, 3~20 modules can be deployed for use. At this time, the relay PDU board 1~19 ports are freely and flexibly deployed. The DC contactor KM2 of any layer of relay PDU board is closed, and KM1, 3~20 are closed. The use of other fast charging guns requires the full flexible deployment of power through the relay PDU boards on the remaining layers; When super charging guns 1 and 16 are working, the power of modules other than PW1 and PW16 can be allocated. At this time, the power can be freely and flexibly allocated through ports 1 to 19 of the relay PDU board. The DC contactor KM2 of any layer of the relay PDU board is closed, and KM1, 3 to 15, and 17 to 20 are closed. The use of other fast charging guns requires the full and flexible allocation of power through the relay PDU boards on the remaining layers.

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