Abstract: When fast voltage control is used in a power factor corrector（PFC），ripples on the DC side can cause grid current harmonics. To solve this problem，a novel DC voltage nonlinear PI control strategy was proposed，which could reduce the harmonic content of fast voltage closed-loop in power factor corrector. Based on the Takagi-Sugeno nonlinear Fuzzy model combined with the PI regulator，the new control strategy was built. The advantage of the new control strategy is that it can not only maintain low harmonic content during the steady-state operation of the system，but also recover quickly from the load transient. The comparative experiments were carried out  etween the new scheme and the traditional linear PI control scheme by the 3 kW single-phase PFC test platform.The test results show that the new nonlinear PI controller can greatly reduce the current harmonics and have the fast dynamic response on the basis of slightly increasing the algorithm complexity.

      Key words: power factor corrector（PFC）；Fuzzymodel；nonlinear control；direct current voltage control