A Band-Stop-Type <i>dv</i>/<i>dt</i> Filter for Terminal Overvoltage Mitigation of SiC Motor Drives

Abstract

The motor terminal overvoltage caused by high <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dv</i>/<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> of devices remains a challenge for silicon carbide motor drives. As a solution, this paper proposes a passive <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dv</i>/<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> filter based on the overvoltage analysis in the frequency domain. The proposed filter adopts an innovative band-stop structure with a parallel connected <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R-L-C</i> circuit. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> provides damping and realizes impedance matching with the cable. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> creates a parallel resonance at a specific frequency for the high-impedance state with a small inductance to mitigate the reflected wave oscillation and obtain selective filtering. The experimental results show that this passive filter can realize similar effects of active filters, while has lower loss and smaller volume than other passive filters.