Simplified logical modulator for the reduction of common mode voltage in alternating current drives

This paper proposes the reduction of common mode voltage (CMV) magnitude using a simplified logical modulator (SLM). This modulator uses the ideas of space vectors to detect and eliminate the high common mode vectors produced by carrier phase-shifted sine pulse width modulation generator. The proposed SLM has an inherent ability to eliminate the CMV spikes due to dead time, but it introduces short circuit vectors (SCVs). This issue is addressed by designing an SCV eliminator (SCVE). The performance of the SLM-SCVE is validated through simulations. The proposed SLM-SCVE is implemented using MATLAB-Xilinx system generator interface in Spartan 3E-FPGA and tested in a prototype hardware. The proposed SLM-SCVE proves to be a simple and reliable solution for the reduction of CMV in industrial application because finite number of logic gates is used.