Implementation of fuzzy logic controller based PID algorithm using a microcontroller

摘要

The application of a simple microcontroller to deal with a three variable input and a single output fuzzy logic controller, with PID response control built-in, has been tested for an automatic voltage stabiliser. The fuzzifiers are based on fixed ranges of the variables of input mains voltage, output current and power factor angle. The control output is used to select the tap on the auto transformer to adjust the voltage, using fuzzy logic principles, so that the voltage is "stabilised". The selection is fed to fire the corresponding triac through a pulse burst from the respective port bit. The use of 89C2051 flash microcontroller with 15 I/O lines enables this application to be conveniently handled.