直接液冷式IGBT模組於電動公車之散熱效能研究

Abstract

近年來，因為絕緣閘雙極電晶體(IGBT, Insulate Gate Bipolar Transistors)模組功率的提升，間接導致散熱的需求也跟著增加，尤其在電動車輛上，如果晶片溫度超過安全範圍，將使車輛無法行駛，並付出額外的修繕成本。

本研究為使用商用軟體ANSYS-Fluent模擬純電動公車用之直接液冷(Direct Liquid Cooling)IGBT功率模組在不同流道設計、質量流率、不同進出口位置與鰭片排列型式等條件下的溫度場、速度場與壓力場，藉以分析各種散熱模組的效益，以求得最佳化的IGBT散熱模組設計。模擬結果可知，有圓角S型與W型在散熱與壓降上有較佳的表現，而透過調整進出口位置和鰭片排列角度，平行流道也可達到更好的散熱效能。此外，並透過結合電動公車上的冷暖機、電池組與馬達之散熱，進行整體系統的熱管理之研究，以達到最大的冷卻效益與廢熱利用。

In recent years, due to increasing power efficiency of an insulated gate bipolar transistor (IGBT) module, the cooling demand of electronic devices has become critical. Especially in the electric vehicles (EVs), if the die temperature exceeds safe limits, the engine system of vehicles will be unable to operate, and pay the extra repair costs.

This study utilizes ANSYS (Fluent) to simulate the heat dissipation, flow velocity field and pressure loss of direct liquid cooling IGBT module in battery electric vehicle (BEV) systems. And according to the simulation results, the optimization of fin shapes, flow channels and locations of inlet and outlet under different boundary conditions can be obtained. Based on different geometries of channel, S type, parallel channel, W type and W+Pin fin type are adopted in this research. The W type has the most ideal performance both in pressure drop and heat transfer from the results. Besides, the thermal management of the whole electric bus was conducted to achieve the best cooling effect and waste heat utilization by combining the heat exchange of conditioners, battery modules and motors.