Dynamic Sliding Mode Control of Active Power Filter With Integral Switching Gain

Owing to the fact that the active power filter with conventional sliding mode controller has a chattering problem, an improved dynamic sliding mode controller is proposed in this paper to increase the performance of the APF. A dynamic sliding mode controller with integral switching gain is developed. The first-order dynamic sliding surface has the characteristic of transferring the discontinuity in traditional sliding mode control to the first derivative of the controller. Therefore, a continuously dynamic sliding controller can be obtained, so that it can effectively weaken the chattering. In the meantime, the appropriate selection of switching gain can also reduce chattering. The simulation results show that the proposed control strategy possesses good performance to suppress the harmonics. Moreover, the hardware in the loop experiment proves the practicability of the proposed algorithm.