Accurate Position Estimation in Switched Reluctance Motor With Prompt Starting

1.0 INTRODUCTION This paper presents a novel method of position estimation for Switched Reluctance (SR) Motor. The method is suitable from starting to full speed. It ensures smooth starting without initial hesitation. The method further incorporates a better position estimating algorithm incorporating corrections for excitation voltage and mutual inductance effects. The algorithm is better suited in a digital control platform for its realisation. Digital signal processor (DSP) with its high computation power has ushered in fresh possibilities for such schemes. In the present work, a general purpose DSP platform is used for the position estimation as well as control of the SR motor. A Texas Instruments make DSP (TMS320c50) is used for this application. 2.0 POSITION ESTIMATION A number of methods have been reported in the literature for the estimation of rotor position in SR motors [1]. Among these methods, those based on the flux-linkage current characteristics have become popular [1, 2]. Figure 1 shows the block schematic of the basis of position estimation. Flux-linkage of any phase is computed from Eq. (1). (1) Ψ = ∫ (V − R i) dt