Thermal Analysis and Heatsink Design for SiC-Based T-Type Inverter

• Other Authors: Miao, Wenjie (authoraut)
• Format: Others
• Language: English; English
• Published: Florida State University
• Subjects: Electrical engineering
• Online Access: http://purl.flvc.org/fsu/fd/FSU_FA2016_Miao_fsu_0071N_13628

Compared to the conventional Si semiconductors, SiC technologies can improve PV converter performance such as a higher power density while leading converters to a higher operating temperature, making the cooling system a significant component. The design of cooling system that optimizes both volume and thermal resistance considering power density and heat dissipation is key to state-of-the-art converters. This thesis will cover the systematic thermal analysis and heat sink design for the SiC-based three phase three level T-type converter (3LT²C). In order to minimize the overall volume of a converter system, it is necessary to derive the maximum thermal resistance as an essential input parameter for the detailed improvement design procedure. Due to the positive feedback of thermal between SiC power device total power losses and its junction temperature, this thesis derived an approximated analytical expression of power loss from both electrical domain and thermal domain to obtain the relationship between the maximum tolerable junction temperature and the maximum heat sink thermal resistance. Considering the manufacturing practical limitations, the improvement design focused on fin height and fan selection with respect to minimum cooling system volume. With a list of considered fans, the non-optimized forced-cooling heat sink of 50 kW 50 kHz interleaved T-type converter will be improved and a plate fin heat sink with fans will be designed for a 100kW 3LT²C system study. Consider the operation conditions for PV grid-tied converter, heat sink under natural convection design with optimized volume are also presented. === A Thesis submitted to the Department of Electrical & Computer Engineering in partial fulfillment of the Master of Science. === Fall Semester 2016. === November 1, 2016. === Cooling system, Forced convection, Heat Sink design, PV inverter, Thermal analysis, T-type inverter === Includes bibliographical references. === Hui Li, Professor Directing Thesis; Jim P. Zheng, Committee Member; Ming Yu, Committee Member.