结温在线控制系统的IGBT功率模块热耦合模型

应用有限元法，对IGBT功率模块的三维热分布进行了仿真研究，得到了器件的稳态热阻及瞬态热阻抗。研究了功率模块各芯片之间的相互热影响，提出了热耦合效应热模型的统一结构，基于对瞬态热阻抗曲线的拟合，得到热模型的相关参数，从而建立了热耦合效应热模型。以一个降压变换器为例，阐述了结温在线控制系统的工作原理，并将热模型应用于该系统中，计算结果与测量结果非常一致。     

高空飞行器供油驱动系统IGBT模块结温特性研究

对高空飞行器供油驱动系统在特定负载状态下的IGBT模块结温特性进行研究。高空飞行器对供油驱动系统的高功率密度要求高及环境散热条件差的状况,使得其关键部件IGBT模块在功率裕量与结温控制方面更为严格。根据负载特性精确计算结温,对于在特定散热条件下系统的可靠运行非常重要。运用非稳态导热的Foster集总参数法,分析IGBT模块点热源特性及其他热源对计算影响,建立一种含校正系数的热网络模型,并在短时脉冲过载及输出低频两种特有状态下,对IGBT模块的结温特性进行分析。通过对高空飞行器飞行过程中IGBT模块结温特性的计算,结合仿真软件Semisel的对比分析,验证了建模和分析本文所提方法的有效性。     

一种用于功率模块热分布特性研究的精确模型

应用有限元法,对一个IGBT功率模块的三维热分布进行了仿真研究,提出了通过ANSYS仿真建立热模型的基本方法,进而探讨了功率模块上各芯片之间的热耦合关系,提出了考虑热耦合效应在内的功率模块热模型的统一结构,基于对瞬态热阻抗曲线的拟合,获得了热模型的相关参数,从而建立了热耦合模型.该模型可方便地应用于电路仿真软件如PSPICE中,仿真结果与有限元计算结果一致,并与实际测量值相符.     

一种用于功率模块热分布特性研究的精确模型

应用有限元法 ,对一个 IGBT功率模块的三维热分布进行了仿真研究 ,提出了通过 ANSYS仿真建立热模型的基本方法 ,进而探讨了功率模块上各芯片之间的热耦合关系 ,提出了考虑热耦合效应在内的功率模块热模型的统一结构 ,基于对瞬态热阻抗曲线的拟合 ,获得了热模型的相关参数 ,从而建立了热耦合模型 .该模型可方便地应用于电路仿真软件如 PSPICE中 ,仿真结果与有限元计算结果一致 ,并与实际测量值相符 .     

一种新型IGBT结温计算模型

为进一步研究IGBT电热参数与结温的关系,提出了一种用于计算IGBT结温的改进电热耦合模型。通过温度循环加速老化试验模拟IGBT的老化过程,记录不同老化程度下IGBT的电热参数,直到IGBT失效。根据电模型和热模型建立电热耦合模型,将不同老化程度下的电热参数及模型相结合,得到改进的电热耦合模型。采用单一参数法,研究了不同老化程度下电热参数对结温的影响。利用IGBT的稳态结温数据,得到电热参数对结温的影响度。     

双馈风电变流器IGBT模块损耗及结温的计算分析及变化规律研究

针对双馈风电变流器IGBT模块在交变热应力的长期作用下导致故障频发的问题,提出其损耗与结温的准确计算模型及不同工况下两者变化规律的研究。首先,建立了机侧及网侧变流器在整流或逆变模式下IGBT模块损耗及结温的计算模型;其次,对机组在不同运行工况下,其损耗和稳态结温进行分析。结果表明,随风速的增大,机侧与网侧变流器IGBT模块的损耗变化规律不同;机侧变流器IGBT模块的结温波动剧烈,尤其是在同步风速附近区域。     

IGBT老化状态下基于BAS-SVM模型的结温预测方法

为进一步研究IGBT老化对其结温的影响,提出了一种新型的结温预测方法。通过功率循环加速老化实验,模拟模块实际运行老化状态,获取了不同老化程度下的饱和压降、集电极电流和结温数据,并进行分析。采用数据驱动的方法,建立了基于天牛须搜索算法优化支持向量机(BAS-SVM)的结温预测模型。结果表明,与粒子群算法-支持向量机(PSO-SVM)模型和天牛须搜索-BP神经网络(BAS-BP)模型相比,BAS-SVM模型更能有效缩短训练时间,收敛速度更快,且对IGBT结温的预测精度更高,是一种更有效的预测模型。     

基于电热耦合模型的功率器件结温预测

结温预测对于功率器件的可靠性分析具有重要意义,基于此,提出了一种基于电热耦合模型的功率器件结温预测方法。首先通过Twin Builder软件建立了绝缘栅双极晶体管(IGBT)的行为模型,通过电路仿真的手段获取IGBT的平均功耗为324 W;然后将IGBT的功耗代入有限元仿真模型中得到了IGBT模块温度场分布,最高温度为99.58℃;最后搭建了IGBT模块结温测试平台,将仿真结果与实验数据进行对比,验证温度场计算模型的有效性;并实验对比了IGBT功耗分别为119 W和294 W下的最高结温,得到的温度场计算误差在10%以内,验证了IGBT有限元模型的有效性。     

晶闸管的瞬态热阻抗及其结温温升的研究

系统地阐述了晶闸管的瞬态热阻抗 ,针对晶闸管承受不同的功率脉冲 ,利用不同的计算方法计算瞬态热阻抗值 ,从而确定结温温升 ,并比较了它们的原理、精度及其应用范围。特别是利用了一种新的瞬态热阻抗计算模型 ,当晶闸管承受持续时间极短且周期、占空比均变化的任意波形功率脉冲时 ,它能够比较精确地分析晶闸管的热特性 ,计算半导体结的最大温升     

晶闸管的瞬态热阻抗及其结温温升的研究

系统地阐述了晶闸管的瞬态热阻抗,针对晶闸管承受不同的功率冲,利用不同的计算方法计算瞬态热阻抗值,从而确定结温温升,并比较了它们的原理、精度及其应用范围。特别是利用了一种新的瞬态热阻抗计算模型,当晶闸管承受持续时间极短且周期、占比均变化的任意波形功率脉冲时,它能够比较精确地分析晶闸管的热特性,计算半导体结的最大温升。     

The effect of electro-thermal parameters on IGBT junction temperature with the aging of module

This paper presents the effect of the change of electro-thermal parameters on IGBT junction temperature with module aging. Five IGBT modules are subjected to advance power thermal cycling, and IGBT I–V characterization, switching loss, and transient thermal impedance curve are measured every 1000 power thermal cycles. Then, electro-thermal models of IGBT module under power thermal cycles were built by change electro-thermal parameters, and the influence of various parameters of the electro-thermal model on the junction temperature was researched respectively. Experimental results demonstrate that IGBT collector-emitter voltage, switching loss and thermal resistance increase more quickly with the aging process of module. Simulation results indicate that the variations of electro-thermal parameters have crucial influences on the IGBT junction temperature. After 6000 power thermal cycles, the IGBT steady state junction temperature mean and variation are increased 1.97 K and 0.1656 K over its initial value, respectively. The relative temperature rise is 38.10% and relative temperature variation is 15.08% after 6000 power thermal cycles. The rise in switching loss increases both the steady state junction temperature mean and variation. The change of thermal impedance has great influence on the steady state junction temperature mean, but has little effect on steady state junction temperature variation.     

Instantaneous junction temperature evaluation of high-power diodes(thyristors) during current transients

In this paper, an approach to the instantaneous junction temperature evaluation of high-power diodes (thyristors) is presented. The model allows obtaining the instantaneous junction temperature waveform starting from the expressions of the device transient thermal impedance and forward voltage drop. The linearity properties of resistors and capacitors (RCs) networks are used to obtain the thermal system transfer function from the transient thermal impedance curve. Thus, an expression that relates the forward voltage drop to the forward current and the junction temperature is used to “feedback” the influence of the temperature variation on the device forward characteristic. The model is also validated by comparing the results obtained from simulation against the one obtained from surge tests performed on one sample device     

Modulation method for measuring thermal impedance components of semiconductor devices

The paper describes the modulation method of measuring the thermal impedance of semiconductor devices as well as its implementation. In contrast to the standard method (JESD51-1 standard) which requires heating the device under test by the stepped power, the modulation method uses heating power modulated harmonically. A pulse sequence of heating current, with the pulse length varying harmonically, is passed through the device under test. The p-n junction temperature is measured through a temperature-sensitive parameter, namely a forward voltage drop on the p-n junction between heating pulses at low measuring current. First harmonic of the p-n junction temperature oscillation is determined by the discrete Fourier transform, which allows to determine thermal impedance absolute value and phase at modulation frequency of heating power. An analysis of the dependence of thermal impedance on modulation frequency allows to determine thermal impedance components corresponding to the structural elements of the device under test. Numerical simulation shows that the thermal resistance components on the Foster's network may be determined at the modulation frequencies corresponding to the first derivative minima of the thermal impedance of the real part of frequency dependence. The main characteristics of the device that implements the method are described.     

High channel density dual operation mode MOS-controlled thyristorwith superior current saturation capability

A 1200-V dual operation mode MCT with low on state voltage drop, high turn-off current and superior current saturation capability has been developed. The dual operation mode MCT overcomes the tradeoff between the on-state voltage drop and the current saturation capability of the conventional IGBT operation by working in a thyristor mode in the on state and in an IGBT mode during the switching transient. This letter reports the device development and demonstrates how the dual operation mode MCT can be beneficial in switching circuit applications     

A study on IGBT junction temperature (Tj) online estimation using gate-emitter voltage (Vge) at turn-off

A novel method is presented for online estimation of the junction temperature (Tj) of semiconductor chips in IGBT modules, based on evaluating the gate-emitter voltage (Vge) during the IGBT switch off process. It is shown that the Miller plateau width (in the Vge waveform) depend linearly on the junction temperature of the IGBT chips. Hence, a method can be proposed for estimating the junction temperature even during converter operation – without the need of additional thermal sensors or complex Rth network models. A measurement circuit was implemented at gate level to measure the involved time duration and its functionality was demonstrated for different types of IGBT modules. A model has been proposed to extract Tj from Vge measurements. Finally, an IGBT module with semiconductor chips at two different temperatures has been measured using Vge method and this method was found to provide the average junction temperature of all the semiconductor chips.     

IGBT关断瞬态电压尖峰影响及抑制

绝缘栅双极晶体管(IGBT)是一种性能优良的全控型电力电子器件,由于线路和器件内部分布电感的存在,关断时集电极电流的快速变化会感应产生一个较大的电压尖峰从而引起过电压击穿。分析了栅极结电容放电时间常数和拖尾电流对电压尖峰的影响,通过改变栅极驱动电阻和温度可以抑制电压尖峰。分析了电压尖峰引起过压击穿的失效机理以及失效模式,表明IGBT过压击穿引起失效的本质仍然是结温过高引起的热击穿失效。     

Transient temperature measurements and modeling of IGBT's undershort circuit

This paper discusses the estimation of possible device destruction inside power converters in order to predict failures by means of simulation. The study of insulated gate bipolar transistor (IGBT) thermal destruction under short circuits is investigated. An easy experimental method is presented to estimate the temperature decay in the device from the saturation current response at low gate-to-source voltage during the cooling phase. A comparison with other classical experimental methods is given. Three one-dimensional thermal models are also studied: the first is a thermal equivalent circuit represented by series of resistance-capacitance cells; the second treats the discretized heat-diffusion equation; and the third is an analytical model developed by building an internal approximation of the heat-diffusion problem. It is shown that the critical temperature of the device just before destruction is larger than the intrinsic temperature, which is the temperature at which the semiconductor becomes intrinsic. The estimated critical temperature is above 1050 K, so it is much higher than the intrinsic temperature (~550 K). The latter value is underestimated when multidimensional phenomena are not taken into account. The study is completed by results showing the threshold voltage and the saturation current degradation when the IGBT is submitted to a stress (repetitive short circuit)