Real-Time Implementation of Sliding Mode Observer for Synchronous Rectification of the Automotive Electrical Power Supply System

Abstract

This paper presents the methods for estimating automotive alternator’s back electromotive forces without a direct mechanical sensor of the rotor position. The design approach combines the merits of the sliding mode observer technique with the basics of a conventional observer. It is shown that the back electromotive forces may be observed based on system’s phase current model by sensing only electrical variables of the synchronous rectifier. Experimental results are presented for validation of the proposed observation algorithms. [S0022-0434(00)01404-0]