In order to improve the working efficiency of the parallel H-bridge active filter, when the power supply voltage is distorted, a more accurate harmonic compensation current is calculated in a shorter time, and an accurate compensation command is provided for the deadbeat control. A control strategy combining adaptive harmonic detection algorithm with carrier phase shift sinusoidal pulse width modulation (CPS-SPWM). Firstly, the reference compensation current is calculated quickly and accurately by the adaptive harmonic detection algorithm. Then, the bridge voltage stability is realized by the outer loop voltage PI control, and the internal loop equalization proportional control is used to realize the same capacitor voltage of the sub-module on the bridge arm. CPS-SPWM provides a more accurate modulated wave signal for active filters. Through simulation experiments, it is verified that the control strategy has higher stability and accuracy than traditional methods.