A Novel Method Utilizing Trapezoidal Voltage to Compensate for Inverter Nonlinearity

The nonlinearity of an inverter could be regarded as the output distortions of the inverter. In this paper, voltages in a trapezoidal form were utilized to compensate for the nonlinearity of an inverter. Undesirable harmonic distortions in the overall system were mitigated through the modulating shape of the trapezoidal voltage. For trapezoidal modulation, a dedicated modulator was designed to facilitate adaptive compensation for a wide operating range. The compensation effects from the proposed method were examined in a practical system, in which a permanent magnet synchronous motor (PMSM) was driven without any position sensor. Additionally, it was shown that the proposed method could enhance the sensorless control of the PMSM by reducing the output distortions of the inverter.