FPGA-based design and implementation of DTC and regenerative braking control of ZSI-Fed an induction motor drive

This paper presents a real-time performance evaluation of direct torque control (DTC) and regenerative braking control of improved z-source inverter fed induction motor drives using field programmable gate arrays (FPGA) based real-time digital simulator (RTDS). RTDS was built using Very High Speed Integrated Circuit Hardware Description Language (VHDL), composing it versatile and compact. The proposed design method was carried out in VHDL, based on MATLAB/Simulink model and also validates the utility of simulating a drive of typical complexity in real-time. The proposed model is executed at fixed time-step and fixed step solver of 10 μs and constant switching frequency is 5 KHz. The proposed design employs much advancement to execute the functional blocks in DTC and regenerative braking that reduce the execution time. The proposed DTC drive technique is capable to change the wide range of motor speed from base speed to zero speed with full load torque. Real-time simulation results are certified the validity of the planned DTC drives and regenerative braking by MATLAB/Simulink interface using Xilinx SPARTAN-3 FPGA board of a 225 KW induction motor fed by the improved z-source inverter (ZSI).