A Current Sampling-Correction Method for Single DC-Link Current Sensor Operation of PMSM Without Motor Parameters

Single current sensor operation (SCSO) in motor drives has garnered significant attention due to its cost-effectiveness and compact dimensions. The conventional SCSO sampling logic, however, results in substantial errors in the reconstructed current. In order to reduce the reconstruction errors, this article proposes a current sampling-correction method for permanent magnet synchronous motor (PMSM) using a five-segment switchable space vector pulsewidth modulation (FSS-SVPWM) combined with cross-period sampling technology. This method does not require any motor parameter. An analysis method for FSS-SVPWM voltage harmonics is presented under steady-state conditions. Additionally, the reconstruction dead zone, correction precision, and switching frequency are discussed. Finally, a 1.5 kW PMSM experimental platform was constructed to verify the performance of the proposed method.