A protection method for safe charging of electric vehicles

Abstract

The invention discloses a protection method for safe charging of an electric car. The method specifically includes the steps of A, over-current protection, B, over-voltage and under-voltage protection, C, over-temperature protection, D, unearthed and live and null wire phase protection and E, earth leakage protection; whether the over-current protection is carried out is determined according to the time of duration of an over-current state; whether the over-voltage and under-voltage protection is carried out is determined according to the time of duration of an over-voltage or under-voltage state; according to the over-temperature protection, the magnitude of charging current is indirectly adjusted by adjusting communication data with a vehicle through an alternating current charging device according to the temperature rise state when a power supply end is plugged; according to the unearthed and live and null wire phase protection, after the alternating current charging device is powered on, whether a power supply wiring state is correct is detected in real time, namely whether earthing is reliable and whether phase dislocation of a live wire and a null wire of the power supply end occurs are detected, and on-off control over a charging power source is carried out according to actual application requirements; according to the earth leakage protection, after the alternating current charging device is powered on, the magnitude of leakage current between the live wire and the null wire and a ground wire in the whole alternating current supply process is detected in real time, and when the leakage current exceeds a set threshold value, charging power supply is cut off. Safe charging is ensured.

Description

technical field

[0001] The invention relates to a protection method for safe charging of an electric vehicle. Background technique

[0002] Electric vehicle (BEV) refers to a vehicle powered by a vehicle-mounted power supply, driven by a motor to drive the wheels, and meets the requirements of road traffic and safety regulations. Due to its smaller impact on the environment than traditional vehicles, its prospects are widely optimistic, but the current technology immature.

[0003] For example, electric vehicles can make full use of the surplus electricity when the electricity consumption is low at night to charge, so that the power generation equipment can be fully utilized day and night, greatly improving its economic benefits. However, due to the immature technology, abnormal situations will occur during the charging process of electric vehicles, resulting in the inability to charge safely and causing potential safety hazards, especially when charging at night when elect...

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