Continuous and Discontinuous SVPWM with Switching Loss Control for Five-Phase Two-Level VSI fed Induction Motor Drive

High frequency performance of variable speed drives with reduced switching losses is merely suitable for precise industrial applications. LC filters are used between a five-phase two-level (FPTL) voltage source inverter (VSI) and a five-phase induction motor (FPIM) to minimize high-frequency losses in the motor, and thus improves the drive performance. It also reduces the high dv/dt at the motor terminals by supplying five-phase sinusoidal voltages. However, this impacts the closed-loop control of the FPIM drive due to sustained resonant frequency oscillations, which destabilizes the drive on certain operational points. Various continuous and discontinuous high-frequency space vector pulse width modulation (SVPWM) techniques are proposed in this paper with detailed analysis. An improved current ripple prediction method is also applied to dampen the resonant frequency and enhance the capabilities of the FPTL FPIM drive. This system is more capable of stable operation without using any auxiliary circuit or high-frequency sensor. Drive stability is tested and verified under different test conditions by simulation as well as experimental results.