Efficiency Comparison of 2-Level SiC Inverter and Soft Switching-Snubber SiC Inverter for Electric Motor Drives

Abstract

This paper focuses on the investigation and implementation of a high-performance power conversion system to reduce the overvoltage phenomenon in variable speed electric drive applications. Particularly, the pros and cons of using Silicon Carbide power MOSFETs in the power converter when a long power cable is employed in electric motor drive systems has been addressed. The three-phase two level inverter with the addition of snubber circuits that consist of capacitors and diodes has been investigated, designed and tested in order to mitigate the overvoltage problems without sacrificing the conversion efficiency. Given that the snubber circuit added to the switches can increase losses, an additional circuit is used to recover the energy from the snubber circuit. The proposed analysis has been then validated through an experimental campaign performed on the converter prototype. The experimental results show that the proposed converter can reduce the overvoltage at the electric motor terminals with excellent conversion efficiency compared to the classical solution like the three-phase two level inverter.

Detailed Power Loss Analysis of T-Type Neutral Point Clamped Converter for Reactive Power Compensation

“…One of the most important features of these converters is high efficiency, which was not always an obvious fact with the greater number of semiconductor devices used in converters with a very high number of voltage levels [10][11][12]. The high efficiency of the converter is an essential parameter because due to low power losses, the converter's lifetime is longer, and the total cost of its operation is lower [13].…”

High-Efficiency and High-Performance Power Electronics for Power Grids and Electrical Drives

“…This Special Issue includes ten contributions on various techniques aimed at improving the efficiency and performance in power electronics applications for power grids and electrical drives [1][2][3][4][5][6][7][8][9][10]. Such articles were authored by international research teams from several countries and covered different topics.…”

“…(a) Power converters used to interface RESs and ESSs with microgrids [1,3,5,7,8,10] or to recharge ESSs in electric vehicles [9]; (b) Performance increase in VSDs and direct online induction motors [4,6]; (c) Application of electrical loss minimization techniques to microgrids based on RESs [2].…”

“…The two contributions that fall into category (b) focused on performance increases in VSDs and direct online induction motors (DOL-IMs). In [4], Di Benedetto et al focused on implementing a high-performance power conversion system to reduce overvoltage in VSDs supplied by SiC-based inverters using long power cables. In particular, a three-phase two-level inverter with snubber circuits based on capacitors and diodes was investigated, designed, and tested to mitigate the overvoltage without sacrificing the conversion efficiency.…”