Modified Sine Triangle Approach For 30-Degree Split Clamp Pulse Width Modulation For Three Phase Voltage Source Inverter

Abstract

Conventional Space Vector Pulse Width Modulation (CSVPWM) uses conventional switching sequence in which near about 15 percent increment can be obtained in voltages compared to Sine Pulse Width Modulation (SPWM). But this method can be further modified into other advanced bus clamping methods called as Bus Clamping Pulse Width Modulation (BCPWM). One of those bus clamping methods is 30-Degree Split Clamp PWM method. It has all the advantages of Conventional Space Vector Pulse Width Modulation (CSVPWM) and it eliminates some disadvantages of traditional technique. In CSVPWM there are only 6 sectors and in 30Degree Split Clamping PWM these 6 sectors are further divided into sub-sectors (12) which allows for a new switching pattern. One of the major disadvantages of 3 phase CSVPWM is that the lower order harmonics of voltages and currents are comparably higher with respect to 30-Degree Split Clamp PWM. Filters can be easily designed for 30-Degree Split Clamp PWM. Even the switching losses are high in case of CSVPWM as switching occurs when the current is maximum depending on the power factor.