Abstract: According to the complex structure of reactive power compensation device on the low voltage side and existing a large amount of flashy flow, a new intelligent low voltage capacitor of high integration, without the freshness and the low cost has been developed based on the technology of  zero-crossing switching. The system model of switching capacitor under different residual voltage are simulated. Compared to the experimental results of inputting with zero network voltage: the flashy flow is low with zero voltage of thyristor.