Application of Fuzzy PID with Loss Balancing Control in Three-level Active NPC Inverter

PID control is widely used in fields of power electronics and electric drives because of its simple algorithm, robustness and high reliability. Due to nonlinearity and time variant of industrial process, traditional PID controller cannot reach high performance. In three-level active neutral point clamped inverter, self-regulation of controller parameters by using fuzzy logic reasoning can decrease effects of variation in load on output characteristics, and using PWM method 1 and method 2 alternately under different conditions can balance losses of power devices to some extent. In this paper, the principle of fuzzy PID control is introduced, and a fuzzy PID controller for three-level active neutral point clamped inverter is designed. A loss balancing modulation method is adopted. The obtained results demonstrate that fuzzy PID control strategy improves dynamic performance of inverter system, compared to traditional PID control.