Dynamic overmodulation characteristics of triangle intersection PWM methods

In this paper, dynamic overmodulation characteristics of current-regulated carrier-based high-performance pulsewidth modulation (PWM) voltage-source i nverter drives are investigated. Dynamic and steady-state overmodulation op erating modes are clearly distinguished, and the requirements for obtaining high performance in each mode are shown to be significantly different. Dyn amic overmodulation characteristics of the modern triangle intersection PWM methods are modeled and shown to be unique for each method, The study reve als space-vector PWM (SVPWM) exhibits a minimum voltage magnitude error cha racteristic. It also indicates all the advanced triangle intersection PWM m ethods, including SVPWM, have limited dynamic overmodulation performance. T o enhance the performance, an algorithm with superior performance is adapte d from the direct digital PWM approach. Detailed induction motor drive simu lations and experimental results illustrate the characteristics of modern t riangle intersection PWM methods and the performance gained with the new dy namic overmodulation algorithm.