Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Comparative Analysis of Pulse Width Modulation Methods for Improving the Lifetime of DC-link Capacitors of NPC Inverters
Authors Jae-Heon Choi ; Ui-Min Choi
Page pp.291-296
ISSN 1229-2214
Keywords Neutral-point clamped (NPC) inverter; Space vector modulation; DC-Link capacitor; Reliability; Lifetime.
Abstract Capacitor is one of the reliability-critical components in power converters. The lifetime of the capacitor decreases as the operating temperature increases, and power losses caused by capacitor current are the main cause of the capacitor temperature increase. Therefore, various studies are being conducted to improve the lifetime of the capacitor by reducing the current of DC-link capacitors. In this study, pulse width modulation methods proposed for improving the lifetime of DC-link capacitors of the three-level NPC inverter are comparatively analyzed. The lifetime evaluation of the DC-link capacitor under different modulation methods is performed at component level first and then system level by considering all capacitors by applying Monte Carlo simulation. Furthermore, their effects on the efficiency and THD of the output current are also considered.