Fast Flux Linkage Measurement for Switched Reluctance Motors Excluding Rotor Clamping Devices and Position Sensors

Abstract

It is essential to experimentally determine the profile of flux linkage, current, and position of a switched reluctance motor (SRM) in both design verifications and high-performance control implementations. In this paper, a fast measurement method of the flux linkage profile is proposed. In the proposed method, the rotor is first rotated to the aligned position, and then, the voltage pulses are applied to all phases simultaneously. The dc voltage and phase current waveforms are recorded to estimate the flux linkage curves at three different positions. These curves are used to calculate the coefficients of a second-order Fourier series flux linkage model, which represents the entire flux linkage profile of an SRM. The feasibility and accuracy of the proposed method are verified by experimental study with an 8/6 SRM. The impacts of rotor misalignment and phase couplings are investigated. A comparative study with the well-recognized rotor clamping method is given to demonstrate the advantages of the proposed method. The proposed method eliminates the requirements on rotor clamping devices or position sensors; therefore, it is suitable for product test in massive production and fast field measurement.