Snubber Network Design for Triac Driving Single – Phase Industrial Heater by Applying Fuzzy Logic Method

Abstract

Power switches require snubbing networks for driving single – phase industrialheaters. Designing these networks, for controlling the maximum allowable rate ofrise of anode current (di/dt) and excessive anode – cathode voltage rise (dv/dt) ofpower switching devices as thyristors and Triacs, is usually achieved usingconventional methods like Time Constant Method (TCM), resonance Method(RM), and Runge-Kutta Method (RKM).In this paper an alternative design methodology using Fuzzy Logic Method(FLM) is proposed for designing the snubber network to control the voltage andcurrent changes.Results of FLM, with fewer rules requirements, show the close similarity withthose of conventional design methods in such a network of a Triac driving 1.2 kWheater of an industrial plastic extruder machine.The similarity, between Fuzzy Logic results and conventional techniquesresults, is confirming the applicability of the fuzzy logic in designing thesesnubbing networks.