Design of an analog fuzzy logic controller for a PWM boost converter

Fuzzy logic controllers (FLCs) have been widely used in many applications, However, they are usually implemented digitally by expensive digital signal processors (DSPs), and the performance is restricted by the sampling period. In this paper, an analog FLC implemented by a low-cost device is proposed. Through analog circuitry, the features of an FLC such as membership function shaping, rule inference and defuzzification are realized. The controller is successfully applied to regulate a PWM boost power converter with satisfactory performance.