A new medium-voltage PWM inverter topology for adjustable-speed drives

In this paper, anew pulsewidth modulation (PWM) inverter topology suitable for medium-voltage (2300/4160 V) adjustable-speed drive systems is proposed , The modular inverter topology is derived by combining three standard thre e-phase inverter modules and a 0.33-pu output transformer. The output volta ge is high-quality multistep PWM with low dv/dt. Further, the approach also guarantees balanced operation and 100% utilization of each three-phase inv erter module over the entire speed range. These features enable the propose d topology to be suitable for powering constant-torque, as well as variable -torque-type loads. Clean power utility interface of the proposed inverter system can be achieved via an Is-pulse input transformer, Analysis, simulat ion, and experimental results are shown to validate the concepts.