1. Composition of Electric Vehicle Charger The car charger is composed of input port, control unit, power unit, low voltage auxiliary unit and output port. 01. Input interface 7 pin ports, three types of connections, including high voltage power connection, high voltage neutral line, vehicle chassis ground, low voltage signal charging connection confirmation and control confirmation. The standard input interface uses a power frequency single-phase input voltage of 220 V, but if the power needs, you can also enable two standby pin ports (pin NC1, NC2), which can achieve 380 V. 02. Control unit The output current and voltage are sampled, and the real-time value is transmitted to the PID control loop after processing. PID: A closed loop automatic control technology, is the proportion, integration, differential control of the abbreviation) The controller compares the difference between the measured value and the expected value, and then passes the adjustment requirements to the PWM loop (PWM pulse width modulation technology). The pulse width variation is used to control the opening and closing time of the power device in the high voltage circuit, and the output current and voltage are as close as possible to the value required by the main control system. 03. Low voltage auxiliary unit The low-voltage auxiliary unit is a standard low-voltage power supply with an output voltage of 12V or 24V, which is used to power electrical appliances on the electric vehicle during charging, such as battery management systems, thermal management systems, automotive instrumentation, etc. 04. Power unit It generally includes three parts: input rectifier, inverter circuit and output rectifier, and converts the input power frequency alternating current into direct current suitable for the voltage of the power battery system.