Voltage Modulation Factor of the Magnetic Flux Control PWM Method

Abstract

The voltage modulation factor of the magnetic flux control PWM method is discussed. The fundamental component of the inverter output voltage is proportional to the radius of the flux locus. The modulation factor is derived by the theoretical study on the length of the flux locus produced from inverter output voltage.
As a result, the modulation factor of the magnetic flux control PWM method is calculated by the portion of zero vectors in the PWM pattern. The modulation factor is proportional to the output voltage from zero to 12/π². By using proposed modulation factor, the magnetic flux control PWM method can control output voltage from zero to over-modulation.
Simulation results and experimental results are also shown.