The basic working principle of YiDian DC charging piles

 The basic working principle of YiDian DC charging piles

The basic configuration of DC charging piles is power unit, control unit, metering unit, charging interface, power supply interface and man-machine interface and other power units refer to DC charging modules, and control units refer to charging pile controllers. DC charging pile itself as a system integration product, in addition to the "DC charging module" and "charging pile controller" two components constituting the technical core, structural design is also one of the keys to the overall reliability design, "charging pile controller" belongs to the category of embedded software and hardware technology, "DC charging module" represents the high achievement of power electronics technology in the field of AC/DC, then, let's understand the basic working principle of Anhui DC charging pile!

The basic process of charging is to apply DC voltage at both ends of the battery to charge the battery with a certain high current. The battery voltage rises slowly to a certain extent, the battery voltage reaches a nominal value, and the SoC reaches more than 95% (varies depending on the battery), continuing to charge the battery with a constant voltage and low current. In order to realize the charging process, the charging pile needs a "DC charging module" to provide DC power in terms of function; A "charging pile controller" is needed to control the charging module's "power-on, power-off, output voltage, and output current"; The "touch screen" needs to be used as a human-machine interface to issue commands, and the controller sends instructions such as "power on, off, voltage output, current output" and other instructions to the charging module. From the electrical side, a simple charging pile only needs to have a charging module, control panel and touch screen; Power on, power off, output voltage" output current and other instructions on the charging module can be charged by typing a few keyboards on the charging module.

The electrical part of DC charging pile consists of a primary circuit and a secondary circuit. The main circuit input is three-phase alternating current, through the input circuit breaker, AC smart energy meter, the charging module (rectifier module) converts the three-phase alternating current into DC power received by the battery, and connects the fuse and charging gun to charge the electric vehicle. The secondary circuit consists of a charging pile controller, a card reader, a display, a DC meter, etc. The secondary circuit also provides "start-stop" control and "emergency stop" operation; The signal provides "standby", "charging" and "full charge" status indications, and the display provides board, charging mode setting and start-stop control operation as an interactive device.

The electrical principles of DC charging piles are summarized as follows:

1. A single charging module is currently only 15kW, which cannot meet the power requirements. Multiple charging modules need to be connected in parallel to work, and a bus is needed to achieve current sharing of multiple modules;

2. The input of the charging module comes from the power grid, which is a high-power power supply, which is related to the power grid and personal safety, especially when it comes to personal safety.

3. The output of the charging pile is high voltage and high current, and the battery is electrochemical, which is explosive. To prevent malfunction safety issues, the output requires a fuse;

4. Safety issues are high priority, in addition to input measures, mechanical locks and electronic locks, insulation inspections, and discharge resistance;

5. Whether the battery accepts charging depends on the brain and BMS of the battery, not the charging pile. From the BMS, the controller sends instructions to the controller on whether to allow charging, whether to stop charging, and how high voltage and current can be charged, which are sent to the charging module.

6. The charging pile is also subject to monitoring and management. The controller must be connected to the network communication module such as WiFi or 3G/4G for background connection;

7. The electricity bill for charging is not free, and the meter needs to be installed, and the card reader needs to realize the billing function;

8. The charging pile shell should have a clear indicator light, generally three indicator lights, indicating charging, fault and power supply respectively;

9.The air duct design of the Yidian DC charging pile is crucial. Besides the knowledge of structure, fans need to be installed in the charging pile, and each charging module has a fan.