A matrix converter-fed sensorless PMSM drive system

This article proposes a novel sensorless adjustable-speed PMSM system. The PMSM system is fed by an ac/ac matrix converter. A standstill starting technique and a flux/rotor estimating technique are proposed. First, by injecting a three-phase detecting voltage signal, the region of the initial shaft position of the PMSM can be obtained. Then, a flux/rotor position estimating technique is used to detect on-line the shaft angle of the PMSM. After that, as a result, a closed-loop PMSM drive system, is achieved. A 32-bit TMS320C40 digital signal processor is used to execute the starting and rotor position estimating techniques and all of the control loops including a current-loop and a speed-loop. The details are discussed in this article. Several experimental results are shown to validate the theoretical analysis.