Real-time performance evaluation of quasi z-source inverter for induction motor drives

This paper demonstrates and validates the real-time performance of quasi z-source inverter (QZSI) for medium voltage induction motor drives using the field-programming gate array (FPGA)-based real-time digital simulator (RTDS). The simulator was built using hardware description language (HDL), making it versatile and moveable. The proposed QZSI-fed drive model is designed in MATLAB/Simulink and implemented on FPGA-based real-time simulator and executed at fixed-time step of 10 μs and constant switching frequency of 5 KHz. The QZSI drive has a unique capability to boost the inverter output voltage during voltage sag and maintain steady state speed of the induction motor. The proposed drive system provides uninterrupted motor speed during voltage sag and removes the crisis in manufacturing and economical losses. Real-time simulation results show steady state and transient performance of QZSI-fed 225 KW, 3.3 KV induction motor drives. The experimental results using RTDS as rapid control prototype controller validate the simulation results.