DTFC Based Indirect Matrix Converter Using Active Flux Concept for IPMSM Drive

An improved direct torque and flux control (DTFC) scheme based on active flux concept for interior permanent magnet synchronous motor (IPMSM) using indirect matrix converter (IMC) is presented in this paper. Active flux concept changes rotor with magnetic poles saliency to nonsalient ones. Rotor position and speed estimation are simplified significantly, because rotor position and active flux position are identical. Torque and flux are controlled independently using PI controllers and four-step switching is used in rectifier bridge of IMC to reduce torque ripple associated with DTC. Removing bulky capacitor of DC link in IMC results in reduced volume and size of converter. Combination of benefits of IMC and DTFC can be achieved using this scheme. Low torque and flux ripples, constant switching frequency, unity power factor regardless of load power factor, wide speed range and low THD are features of proposed scheme.