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关键词： Thermal performance   Energy conservation   Field synergy   Entropy generation  

摘要： A thermal-and-energy-conservation optimization was numerically investigated in this work for a liquid-cooled plate (LCP). Firstly, a three-dimensional model was established, and its numerical analysis was verified with experimental data. Then, the common correlations of heat transfer synergy beta and pressure synergy theta involving the amplification factor, the width of cooling columns, the number of cooling columns, the height and the width of flow passage were derived from the traditional Colburn factor j and Fanning friction factor f correlations, which were later solved by the least-square method and tested with regression and joint hypotheses test. With those correlations, a multi -objective optimization was performed, and its outcomes were assessed by a comprehensive evaluation index Comprehensive synergy gamma for thermal performance and auxiliary entropy generation for energy conservation. At last, Optimized Scheme 2 (OS2) was numerically compared with the original one to confirm improvements. It is found that, over the whole speed range, the maximum error between both results is 6.61 %. The test shows that the fitting correlation may predict 94.79 % of beta with a -0.039 % mean error and 98.96 % of theta with a 0.099 % mean error. Among outcomes, OS2 contributes a better gamma, 51.3465 degrees, for thermal performance and a smaller entropy generation, 0.09175 W/K, for energy conservation. Furthermore, the comparison also supports that finding with the decreased beta of 0.39 %, the decreased theta of 3.33 %, the increased gamma of 0.34 %, and the increased entropy generation of 3.99 % in OS2. The research results can provide a basis for the design and development of a high -power loader.

关键词： Insulated gate bipolar transistors   Monitoring   power semiconductor devices   reliability   temperature measurement  

摘要： Insulated gate bipolar transistor (IGBT) junction temperature monitoring is crucial for IGBT reliability assessment and health management. However, most traditional methods are involved with calibrating current, which increases the complexity of the practical application. In this article, an IGBT junction temperature monitoring method current calibration free based on the narrow pulse injection is proposed. A narrow pulse is injected in the expected current, which allows temperature monitoring at a fixed current value, thus avoiding the current calibration. Besides, the voltage overshoot of the narrow pulse has a linear relationship with IGBT junction temperature. The dependence of narrow pulse voltage overshoot on junction temperature is analyzed in detail. The setup of narrow pulse injection is introduced. The experiments are conducted, and the feasibility of the proposed method is verified. Moreover, considering a typical permanent magnet synchronous motor as the load, the effect of a narrow pulse on load is analyzed. The analysis results indicate that the influence of narrow pulse injection is tiny for a motor load. The IGBT junction temperature monitoring method based on the narrow pulse injection has the advantages of no current calibration and high monitoring resolution and flexibility.

关键词： SiC Mosfet   IGBT   electro-thermal model   power losses   lifetime   mission profile   rainflow counting   failure cycles   accumulated damage  

摘要： The lifetime of power electronic systems is the focus of both the academic and industrial worlds. Today, compact systems present high switching frequency and power dissipation density, causing high junction temperatures and strong thermal fluctuations that affect their performance and lifetime. This paper is a review of the existing techniques for the electro-thermal modelling of Mosfet and IGBT devices regarding lifetime estimation. The advantages and disadvantages of the methodologies used to achieve lifetime prediction are discussed, and their benefits are highlighted. All the factors required to predict power electronic device lifetime, including Mosfet and IGBT electrical models, the computation of power losses, thermal models, temperature measurement and management, lifetime models, mission profiles, cycle counting, and damage accumulation, are described and compared.

关键词： surge current   active short circuit   wide-band gap   electrical vehicle   drive inverter   GaN HEMT   SiC MOSFET   SiC JFET   Si IGBT   Si diode  

摘要： This paper will evaluate the surge current robustness of different devices in relation to the active short circuit (ASC). For the purposes of this study, a Si IGBT and its diode, two SiC MOSFETs with different voltage ratings, a SiC JFET, and three GaN HEMTs will be compared. For the GaN devices, a eMode, a dMode, and a cascode device are employed. With the exception of the Si diode, all devices exhibited a current saturation effect. This saturation will result in significant losses and, ultimately, a thermal defect. For all devices, a safe operating area (SOA) criterion is established. For the SiC and GaN devices, the saturation voltage can be employed to define the safe operating area (SOA) criterion. In this context, two on-state resistance models will be defined for these devices. One is solely temperature-dependent, while the other also considers current saturation. Consequently, the saturation voltage and the on-resistance model represent a straightforward methodology for evaluating the ASC robustness of the devices. For all devices, a recommendation for a loss model and SOA criterion will be provided. Finally, the surge current robustness of all devices is compared. The Si, SiC and GaN devices exhibit comparable high surge current robustness in the application, with the exception of the GaN eMode, which is susceptible to strong current saturation.

关键词： Insulated gate bipolar transistors   Mathematical models   Equivalent circuits   Integrated circuit modeling   Power supplies   Voltage   Layout   Current sharing   electromagnetic coupling   Experimental Advanced Superconducting Tokamak (EAST)   multiphysics domain co-simulation   partial element equivalent circuit (PEEC)  

摘要： In the Experimental Advanced Superconducting Tokamak (EAST) poloidal-field power supply (PFPS), the necessity of paralleling high-power IGBT modules within each IGBT bridge arm unit is underscored by substantial power requirements. This study aims to enhance current sharing among these modules, focusing on module layout and copper bar structure optimization. Utilizing the partial element equivalent circuit (PEEC) method, we model the stray inductance in the commutation circuit, considering the skin and proximity effects in laminated busbars. A novel input structure is proposed to improve the current sharing without affecting the unit's overall inductance, incorporating heat dissipation and dc-link capacitor layout into the bridge arm unit's design. This article's main contributions include detailed PEEC-based electromagnetic modeling and a new design enhancing current sharing in 3IGBT parallel modules, validated by multiphysics co-simulation. These simulations confirm our approach meets the system's compatibility, stress, current sharing, and temperature criteria, marking significant progress in high-power IGBT module application in fusion power systems. This article not only presents a practical solution to current-sharing challenges but also sets the groundwork for future advancements in power electronics design.

关键词： Nuclear power plant rod position indicating   and rod control system   IGBT   Feature extraction   SDAE   LSTM   Life prediction  

摘要： To reduce the losses caused by aging failure of insulation gate bipolar transistor (IGBT), which is the core components of nuclear power plant rod position indicating and rod control (RPC) system. It is necessary to conduct studies on its life prediction. The selection of IGBT failure characteristic parameters in existing research relies heavily on failure principles and expert experience. Moreover, the analysis and learning of time-domain degradation data have not been fully conducted, resulting in low prediction efficiency as the monotonicity, time correlation, and poor anti-interference ability of extracted degradation features. This paper utilizes the advantages of the stacked denoising autoencoder(SDAE) network in adaptive feature extraction and denoising capabilities to perform adaptive feature extraction on IGBT time-domain degradation data;establishes a longshort-term memory (LSTM) prediction model, and optimizes the learning rate, number of nodes in the hidden layer, and number of hidden layers using the Gray Wolf Optimization (GWO) algorithm;conducts verification experiments on the IGBT accelerated aging dataset provided by NASA PCoE Research Center, and selects performance evaluation indicators to compare and analyze the prediction results of the SDAE-LSTM model, PSOLSTM model, and BP model. The results show that the SDAE-LSTM model can achieve more accurate and stable IGBT life prediction.

关键词： IGBT并联   均流特性   驱动差压   异步间隙  

摘要： 动态均流是限制多IGBT模块并联应用的关键问题。开通电流时刻，电流上升率和电流峰值等过程变量形式影响多支路IGBT开关过程的一致性。基于并联支路IGBT驱动控制回路的固有参数差异，该文提出并联IGBT差压异步驱动技术，通过调节驱动脉冲异步间隙和改变驱动电压幅值与持续时间，协调控制不同支路的IGBT门极脉冲，驱动各支路IGBT开关过程电流一致。研究开关过程中驱动信号异步间隙、驱动差压与电压调整时间对动态电流斜率不均衡度的影响，分析控制参数耦合关系，优化参数设定方法。基于实际IGBT模块参数，建立器件工作特性数学模型，进行IGBT并联开关仿真分析，开展应用该方法的驱动实际工况测试，结果表明，所选优化设计参数可以明显改善IGBT模块并联开关动态均流特性，验证了差压异步驱动控制优化参数设计方法的可行性。

摘要： In this paper we present measurement results of hot-carrier-induced degradation of NPT-IGBT under the condition of voltage applied on its collector. The effect of hot carriers on NPT-IGBT is investigated in three ways: stress test measurement according to the gate voltage under the voltage of 400 V applied, TCAD (Tsuprem4 and MEDICI) simulation and electric charge pumping test measurement. The experimental results confirm that the proposed structure of NPT-IGBT has sustainable characteristics and enables the hot-carrier-induced degradation to be effectively optimized in order to guarantee the stability of the device.

关键词： 自适应动态规划   折扣衰减项   最优控制   灵活性   神经网络  

摘要： 针对离散仿射非线性系统,利用自适应动态规划提出了一种新的带有折扣衰减项的最优控制方法.首先,引入了衰减项构造性能指标函数,克服了传统研究中折扣因子忽略后续时刻对系统性能的影响,提高了系统的控制性能.其次,不同于传统的折扣因子算法,本文对性能指标函数序列进行分析,证明了折扣衰减项能够提高系统的灵活性,避免传统迭代过程中的局部收敛问题,并利用神经网络实现了该算法.接着,构造了单调递增或递减的迭代性能指标函数序列并证明了系统的渐进稳定性.最后,通过仿真实例验证了算法的有效性.

关键词： IGBT   数据驱动   老化参数   迁移学习  

摘要： 针对绝缘栅双极型晶体管(IGBT)的健康状态及剩余使用寿命评估问题，本文基于迁移学习AdaRNN模型预测IGBT的老化参数。首先分析IGBT的失效机理，选择集电极-发射极导通电压作为评价IGBT健康状态的老化参数；然后搭建IGBT老化实验台，在线采集该老化参数；最后基于采集的老化参数，利用AdaRNN模型实现IGBT老化参数预测。结果表明，使用同一IGBT老化参数作为训练集与测试集时，传统时序模型和AdaRNN模型预测结果的精度与速度相似；使用两组不同IGBT的老化参数作为训练集与测试集时，AdaRNN模型可解决由于器件差异导致的老化参数差异问题，预测的准确度明显高于传统时序模型，模型的泛化能力和鲁棒性强。