Energy storage multi-pack parallel connection charging system

Abstract

The utility model discloses a kind of energy storage multi-PACK parallel machine charging systems, applied to parallel machine charging field, for the consistency of battery is not unified, the whole system of existing parallel machine charging, there is difficult to make all machines reach the problem of full condition of battery;Energy storage host computer in the utility model is connected with PCS through CAN bus, and each power bus connected with PCS and each energy storage machine is provided with a switch, the switch is closed, then the power line between energy storage machine and PCS is communicated, and the switch is opened, then the power line between energy storage machine and PCS is disconnected.

Description

Technical Field

[0001] This utility model belongs to the field of parallel charging, and specifically relates to a parallel charging system. Background Technology

[0002] When the system is charging in parallel, due to the certain error in battery energy calculation, the existing technology generally defines the full charge condition based on voltage. For series-connected batteries, the cell with the highest voltage needs to be selected for protection to define full charge. However, due to the inconsistency of batteries, in the entire parallel charging system, one machine may have the highest cell voltage that has reached the full charge condition, while other machines may not have reached the full charge condition at all. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model proposes a multi-pack parallel charging system for energy storage. By controlling the on / off state of the power bus connection between the PCS and each energy storage unit through a switch, the system can achieve the effect of fully charging one energy storage unit and disconnecting it from another, thereby ensuring that each energy storage unit can be fully charged.

[0004] The technical solution adopted by this utility model is: an energy storage multi-pack parallel charging system, including: PCS, several energy storage units, CAN bus, power bus and several switches, the number of switches being equal to the number of energy storage units, one CAN bus of the energy storage unit being connected to the PCS, and another CAN bus being connected to each energy storage unit respectively; one end of the power bus is connected to the PCS, and each energy storage unit is connected to the other end of the power bus through a switch.

[0005] The beneficial effects of this utility model are as follows: By connecting the power bus of the PCS to each energy storage host via a switch, this utility model enables independent charging of each energy storage host. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the present invention. Detailed Implementation

[0007] To facilitate understanding of the technical content of this utility model by those skilled in the art, the content of this utility model will be further explained below with reference to the accompanying drawings.

[0008] To achieve maximum system capacity and fully charge each machine, this invention requires a protection mechanism to prevent the fully charged machine from requiring further charging. Figure 1 As shown, the technical solution adopted by this utility model is as follows: the connection between the PCS and each energy storage host includes a CAN bus connection and a power line connection. The power bus connection between each energy storage unit and the PCS is controlled by a contactor. The PCS also connects to the power grid (i.e.,...). Figure 1In the Gird), photovoltaic modules (i.e. Figure 1 The PV (Power, Transmission, and Display) connection is used to stop charging of the charger or inverter, disconnect the contactor of the fully charged machine, and remove it from the charging process. Then, the charging equipment is restarted, and each remaining parallel-connected machine is removed one by one in this manner until all machines are fully charged. Finally, the removed machines are reconnected one by one according to the parallel connection conditions, ending the charging process. Here, the contactor is an electromagnetic switching device, such as... Figure 1 The symbols are represented as KM1, KM2, ..., KMn, where KM is a general code for contactors.

[0009] Throughout the process, the conditions for cutting off fully charged machines need to be determined based on external charging conditions. If the machine is grid-connected, the fully charged machine can be cut off while the others continue charging. If the machine is off-grid, the charging process depends on the external photovoltaic (PV) conditions. If there is sufficient sunlight, the fully charged machine can be cut off while the others continue charging. If there is insufficient PV, charging is not necessary, and the charging equipment is placed in a state where charging is prohibited and discharging is permitted, thus ending the charging process.

[0010] The system provided by this utility model can fully charge each device as much as possible according to the actual application scenario, thereby maximizing the use of system capacity. If the traditional method is used, one device is fully charged and then the others continue to charge. In the off-grid state, if one device is disconnected, the photovoltaic power is very weak and cannot be charged, and the system cannot be used. However, with the technical solution of this utility model, the system can be used normally without hindering the user.

[0011] If the entire system stops charging once a device is fully charged, then devices that are not fully charged will remain in a low-power state for a long time, and the system will not utilize its maximum capacity.

[0012] The application scenarios can operate in both grid-connected and off-grid conditions. If the grid power in the diagram fails, it can be charged through photovoltaic or other means. Therefore, there are multiple methods, and the corresponding control methods should be selected according to the scenario.

[0013] The charging system of this invention can provide power to the load. The charging of the battery in the charging system of this invention and the power supply to the load based on the system of this invention are both performed by the PCS. The battery cluster in the charging system of this invention only needs to interact with the PCS to tell the PCS whether it can be charged or discharged. The PCS will then charge or discharge the battery in the charging system of this invention accordingly.

[0014] Those skilled in the art will recognize that the embodiments described herein are for the purpose of helping to understand the principles of this invention, and should be understood that the scope of protection of this invention is not limited to such specific statements and embodiments. Various modifications and variations can be made to this invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of the claims of this invention.

Claims

1. A multi-pack parallel charging system for energy storage, characterized in that, include: The system consists of a PCS, several energy storage units, a CAN bus, a power bus, and several switches. The number of switches is equal to the number of energy storage units. One CAN bus of the energy storage unit is connected to the PCS, and the other CAN bus is connected to each energy storage unit. One end of the power bus is connected to the PCS, and each energy storage unit is connected to the other end of the power bus through a switch.

2. The energy storage multi-pack parallel charging system according to claim 1, characterized in that, The PCS is also connected to the power grid.

3. A multi-pack parallel charging system for energy storage according to claim 1 or 2, characterized in that, PCS is also connected to photovoltaic modules.

Images