Impact of Slim DC Capacitance on Floating Capacitor H-bridge Motor Drive

Abstract

This paper discusses the impact of small DC capacitance in a motor drive using a floating capacitor H-bridge topology. Special attention is paid on investigating the 2 nd order DC capacitor voltage ripples, whose influence on the induction motor as well as on the motor drive itself is of importance. This issue is addressed in this paper through rigorous mathematical formulations. It is found that by inverting 2 nd order DC ripple voltage using conventional SVPWM, no harmful harmonics will be generated in the motor line voltage. This demonstrates the possibility of drastically reducing the DC capacitance of the proposed system. Induction motor as well as H-bridge performance with respect to different DC capacitance is demonstrated by experiments, which lays the foundation for cost reduction and reliability enhancement of the proposed system.

Reduction of DC Capacitor Size in Three-Phase Input/Single-Phase Output Power Cells of Multi-Cell Converters through Resonant and Predictive Control: A Characterization of Its Impact on the Operating Region

“…The first factor directly depends on the criteria used to design the DC-link capacitor bank to achieve correct operation of the inverter. Two typical criteria for sizing the DClink capacitor are the admissible ripple and the required ride-through capability [9][10][11][12][13][14][15][16].…”