The wideband residual current sensitivity detection and protection based on DC charging pile application

With the rapid development of electric vehicles, the construction and use of charging piles have gradually become key infrastructure for promoting their widespread adoption. However, many current charging piles, when performing smooth DC charging, experience excessive accumulation of residual current, which leads to current fluctuations during the charging process, affecting the stability and lifespan of the equipment. To address this issue, this paper proposes a method for suppressing residual current in smooth DC charging based on fluxgate control technology. This method precisely regulates the residual current fluctuations in charging piles, thereby improving the stability of the charging process. The method achieves detection of low-frequency signals at 600Hz, as well as signals in the range of 600Hz to 20kHz. The prototype transformer developed meets the application requirements for residual current protection in electric vehicle charging piles. This research provides a new technical path for the efficient and stable operation of charging piles.