Performance study of advanced discontinuous SVPWM methods with zero changing angle variation

This paper evaluates the performance of conventional and advanced discontinuous space vector pulse width modulation(PWM)with the variation in placement of clamping position (zero vector changing angle). This paper investigates the effect of various clamping sequences on THD and on switching loss. The variation in clamping sequences over the different region of a sector and its placements are carried out. The measure of THD performance and switching loss are evaluated based on flux ripple analysis and the variation of angle between line current and line voltage respectively. The switching loss mainly depends on the modulating wave shape and fundamental power factor in bus clamped PWM. Different SVPWM switching strategies are implemented using a low cost PIC micro controller (PIC18F452)to drive IGBT based 2 KVA voltage source inverter(VSI) with a DC bus voltage of 400 V. The experimental results and waveforms are demonsrated for 415V, 2hp, 50Hz, 3-phase Induction motor under noload and with load conditions. The comparative results for clamping strategies for variation in clamping position of a phase reveals that the advanced split and continual clamped SVPWM strategy has less switching loss compared to the other strategies.