Aplicação de Inversores Multiníveis para Redução do Conteúdo Harmônico das Correntes de uma Máquina PMSM N˜ao-Senoidal
Keywords: Indirect field oriented control, Multilevel inverter with flying capacitor, Non-sinusoidal permanent magnet synchronous machine, Phase-shifted modulation
AbstractThis work presents the use of multilevel inverters in a non-sinusoidal permanent magnet synchronous machine to reduce the harmonic content in the currents. Due to the con- struction of this machine, the back electromotive force presents a non-sinusoidal characteristic, which has as main consequence the presence of ripple in the electromagnetic torque produced by the machine. Such oscillations decrease the efficiency of the machine, and can cause vibrations in the motor shaft, reducing its useful life. To mitigate this, this work uses multilevel inverters with flying capacitors to synthesize voltages with 3, 5, 7 and 9 levels, in order to reduce the harmonic content of the stator currents, and consequently the machine torque. Qualitative analyzes are presented through the total harmonic distortion and ripple in the machine currents, and the weighted total harmonic distortion of the inverter output voltages, comparing the performance of multilevel inverters with a half-bridge inverter of 2 levels.