Rising and Falling Current Methods for Measurement of Flux-Linkage Characteristics of Switched Reluctance Motors: A Comparative Study

Switched reluctance motor has a doubly salient structure, where flux linkage is dependent on both rotor position and phase current. Hence, measurement of flux-linkage characteristics is difficult compared to other motors. One popular method is the DC-excitation method, where flux-linkage can be computed by first measuring phase voltage and current when the current is rising/falling while a fixed DC/zero voltage is applied to a phase winding with rotor being locked at a specific position, and, later, by numeric integration of induced phase voltage determined from Faraday´s Law. This paper reports a comparative evaluation of results from rising and falling current methods both under static and dynamic conditions. All the calculations are based on developed MATLAB/SIMULINK computational model. The measurement procedures are explained in detail.