Advanced IGBT Module Design for Enhanced Overcurrent Capability Using Phase Change Materials

Abstract

Abstract. This paper presents a novel insulated-gate bipolar transistor (IGBT) power module design that integrates phase change material (PCM) above the chips, coupled with an optimized metal frame, to enhance overcurrent (OC) capability during low-voltage ride-through (LVRT) events. Transient thermal simulations using ansysfluent were conducted to evaluate the module's performance under varying OC scenarios, with mesh independence verification and simulation validation performed to ensure accuracy. The results demonstrate that the proposed IGBT module design significantly outperforms existing methods by offering faster thermal response and substantially reducing the steady-state operating temperature. When initially operating at 90% of the rated current, it can sustain current of 1.5 p.u. for 7.05 s, 2.0 p.u. for 1.91 s, and 3.0 p.u. for 0.37 s—over eight times longer than the original commercial module's withstand time. The integration of PCM absorbs the majority of the upward-transferred thermal power, resulting in a 5 °C to 7 °C reduction in junction temperature compared to a solid copper block. The study also identifies the optimal PCM container height for different OC levels and highlights the latent heat of the PCM as a key factor in enhancing thermal management. The proposed design effectively enables IGBT modules to provide multiple times their rated current for reactive current injection during LVRT without compromising reliability, contributing to improved grid stability and supporting the increasing integration of renewable energy sources (RES).