并联IGBT占空比的温度特性建模与分析  

Modeling and Analysis of Temperature Characteristics of Parallel IGBTs Duty Cycle

作　　者：黄海宏[1] 彭岚 王海欣[1] Huang Haihong;Peng Lan;Wang Haixin(School of Electrical Engineering and Automation Hefei University of Technology Hefei 230009,China)

机构地区：[1]合肥工业大学电气与自动化工程学院,合肥230009

出　　处：《电工技术学报》2024年第14期4422-4431,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金区域创新发展联合基金资助项目(U22A20225)。

摘　　要：并联IGBT是解决托卡马克(Tokamak)装置中等离子体垂直位移快速控制电源容量逐渐增大问题的有效途径。而并联IGBT之间的结温平衡是并联系统安全稳定运行的关键因素之一。因此,研究结温对并联IGBT功率损耗差异的影响对提高并联系统的稳定性至关重要。然而现有的研究成果主要集中在单个器件损耗模型或者是并联IGBT的最佳工作频率范围而未涉及对并联IGBT最佳工作占空比范围的讨论。研究发现,当IGBT工作在正温度系数区间时,结温差异造成的通态损耗差异与开关损耗差异呈不同的温度特性。因此,提出零温度-占空比的概念来估计并联IGBT之间结温失配趋势。该文建立零温度-占空比模型,并以此来分析电路设计参数、IGBT器件参数以及结温差异对并联IGBT最佳工作占空比范围的影响。实验结果表明,通过零温度-占空比模型可以对并联IGBT的可靠性、电路设计参数以及器件选型提供可行的参考。IGBT parallel connection effectively solves the problem of increasing the power supply capacity for plasma vertical displacement fast control in Tokamak devices.However,in the working process of parallel devices,due to the inconsistency of device parameters,stray parameters in the circuit,driver parameters,and heat dissipation system parameters between IGBTs,loss differences always exist between parallel IGBTs,resulting in junction temperature differences.The junction temperature difference may increase the loss difference between IGBTs,potentially leading to overheating and failure.However,the existing research mainly focuses on the loss model of a single device or the optimal operating frequency range of parallel IGBTs.The optimal operating duty cycle range of parallel IGBTs is rarely discussed.It is found that when the IGBT device works in the range of a large current positive temperature coefficient,the on-state loss differenceΔEc and the switching loss differenceΔEsw caused by the junction temperature differenceΔTj show different temperature characteristics.Therefore,there is a zero temperature-duty cycle D0,where the duty cycle of parallel IGBTs operates on both sides of the zero temperature-duty cycle.The total loss difference shows two different temperature characteristics,indicating distinct junction temperature mismatch trends.In this paper,the duty cycle range beneficial to IGBT parallel operation is called the optimal duty cycle range.Since the duty cycle is closely related to the operating current of the IGBTs,reasonably improving the loss model of the parallel IGBTs is a challenge to analyze the duty cycle and junction temperature difference.Therefore,taking the BUCK transformation as an example,this paper makes a linear assumption on the switching behavior of parallel IGBTs to simplify the loss model and proposes a zero temperature-duty cycle analysis model.Accordingly,the influence of circuit design parameters,IGBT device parameters,and junction temperature difference on the zero temperature-du

关 键 词：并联IGBT 开关损耗 导通损耗 温度特性 零温度-占空比 

分 类 号：TM91[电气工程—电力电子与电力传动]