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关键词： 恒压供水   变频器   循环水  

摘要： 本文通过对现有生产供水系统的工艺介绍,探讨了将之升级为变频器恒压供水技术的可行性,揭示了恒压供水技术对整个供水管网系统所产生的积极影响。实践证明,采用变频器恒压供水技术进行系统改造,不仅确保了厂区供水的稳定,而且实现了水资源和电能的节约,取得了较好的经济效益和社会效益。

关键词： Capacitors   Insulated gate bipolar transistors   Voltage   Capacitance   Vectors   Topology   Rectifiers   Inverters   Discharges (electric)   DC-link series insulated-gate bipolar transistor (IGBT)   permanent magnet synchronous motor (PMSM) drive system   small dc-link capacitor   space vector pulsewidth modulation (SVPWM)   space vector pulsewidth modulation (SVPWM)  

摘要： In this letter, a series insulated-gate bipolar transistor (IGBT) chopping strategy based on space vector pulsewidth modulation (SVPWM) is proposed for a permanent magnet synchronous motor drive system with small dc-link capacitance and IGBT connected at the dc link. Based on the maximum output capability of the SVPWM technique, this letter clarifies the minimum dc-link voltage constraint based on the voltage vector angle and proposes a series IGBT chopping strategy that ensures the dc-link voltage always satisfies this constraint. The small capacitor cut into the dc link by turning on the series IGBT for only a portion of each rectification cycle, thereby the required capacitance can be reduced. Simultaneously, the normal operation of the drive system can still be guaranteed. The effectiveness of the proposed strategy is validated through experimental results.

关键词： Insulated gate bipolar transistors   Couplings   Vibrations   Temperature   Three-dimensional displays   Fatigue   Finite element analysis   Thermal loading   Transient analysis   Stress   Crack damage   extended finite element   fatigue propagation   insulated gate bipolar transistor (IGBT)   thermal vibration load  

摘要： Insulated gate bipolar transistor (IGBT) is one of the most important power modules in electric traction converter systems. However, the IGBT module may suffer from alternating thermal load and frequent vibration impacts, which will cause crack damage and propagation in the solder layer, resulting in early failure. In this article, the 3-D extended finite element method (XFEM) is used to investigate the fatigue propagation characteristics of crack damage in the solder layer of an IGBT module, where the coupling effects of transient temperature and mechanical fields are considered. The thermal-vibration coupling relationship and periodic fatigue propagation of crack damage are analyzed by using XFEM. The distributions of stress, strain, and crack damage evolution state under different thermal-vibration loads are obtained. Based on the fracture mechanics theory and Paris equation, the dynamic crack propagation and damage fatigue evolution of the IGBT solder layer under periodic coupling stress are revealed. Results show that the thermal-vibration coupling effect causes the crack damage propagation of the IGBT solder layer and the change of crack damage fatigue propagation rate. The results of this research may contribute to the failure mechanism and fatigue life prediction of high-power module IGBT devices.

关键词： Temperature measurement   Insulated gate bipolar transistors   Calibration   Temperature distribution   Junctions   Voltage measurement   Semiconductor device measurement   Insulated gate bipolar transistor (IGBT)   temperature distribution   junction temperature (T-j)   ON-state collector-emitter voltages (V-ce)   ON-state collector-emitter voltages (V-ce)  

摘要： Online junction temperature (T-j) estimation for power semiconductor device insulated gate bipolar transistor is of great importance for reliability assessment and enhancement. Typically, T-j can be online calculated using the pre-calibrated correlation with on-state collector-emitter voltages (V-ce) at loading current. However, the uneven temperature distribution inside the device during calibration is different from the conditions during operation. Uneven thermal distribution inside the device and self-heating of chips will cause significant estimation error by using the pre-calibrated T-j - V-ce correlation, as the voltage drop on interconnections will be different. In this article, a novel calibration method of T-j - V-ce relationship under pulsewdith modulation operation of device is proposed. By varying the switching frequency with fixed heatsink temperature, adjustable self-heating conditions and temperature distributions inside the device can be recreated. Moreover, a group of new relationships between junction temperature, heatsink temperature and temperature of interconnections inside device are revealed. By using the discovered relationship, the influence of uneven temperature distribution on V-ce can be compensated in a noninvasive way, which can achieve higher accuracy in T-j estimation compared to the conventional method.

关键词： converter cooling   MHPA   thermal resistance analysis   multi-condition experiments   numerical simulation  

摘要： Overheating failure is one of the common causes of motor converter failure, so it is very important to improve the heat dissipation of the converter. In response to the inefficiency of traditional converter heat dissipation devices, we propose a novel heat dissipation device. The device combines micro-heat pipe arrays (MHPAs) and interleaved fins, and the MHPAs were initially applied in the converter. The device leverages the exceptional thermal conductivity of the MHPA to rapidly transfer heat from the heat source to various parts of the fins, ultimately achieving efficient heat dissipation and lowering the temperature. This study investigates the thermal resistance, heat dissipation performance, and overall temperature distribution of both the new and traditional heat dissipation devices using theoretical modeling, multi-condition experimental comparisons, and numerical simulation analysis. The experimental results demonstrate that the new heat dissipation device exhibits lower thermal resistance, higher heat dissipation, and greater convective heat transfer intensity compared to the conventional device. In a scenario with 6.3 kW power and 4.3 m/s wind speed, the new heat dissipation device decreases thermal resistance by 15 times, boosts heat dissipation by 30%, enhances convective heat transfer by 12.5%, and lowers the heatsink object temperature by 30%. As power and wind speed increase, the heat dissipation performance of the new heat dissipation device can be further improved. Additionally, the new heat dissipation device exhibits a characteristic where the temperature of the fins is higher on the outside and lower on the inside. Increasing the length of the fins helps improve the device's heat dissipation performance. The feasibility of the MHPA being applied in converter heat dissipation systems is validated in this study. This device significantly enhances converter heat dissipation efficiency and is crucial for advancing the high-power capabilities of moto

关键词： Insulated gate bipolar transistors (IGBT)  

摘要： Addressing the criticality of IGBT modules in power electronics and reliability challenges in industrial applications, this study focuses on solving the important problem of solder layer aging failure in IGBT modules. Under defined operating conditions, a specific set of electrical parameters, notably the collector-emitter saturation voltage Vce (sat) , serves as a critical indicator for monitoring the degradation of solder layers within IGBT modules. This parameter is indicative of potential solder layer aging failures, which can be identified and studied to predict and mitigate such failures effectively. In order to analyze the aging trend more deeply and accurately, a new nature-inspired meta-heuristic algorithm based on Crested Porcupine Optimizer is introduced. Combining multiple data during the operation of the IGBT module, such as gate voltage, gate current, heatsink temperature, case temperature, collector-emitter current, and Vce (sat) , the parameter optimization is carried out by using CPO, and a prediction model based on the optimization of the SVR by CPO is established, which is successfully implemented to predict the accurate prediction of IGBT module solder layer lifetime. The study also validates the effectiveness of the CPO-SVR method on an accelerated aging dataset of IGBT modules provided by NASA Lab. The results of this research contribute to an in-depth understanding and prediction of the aging process of IGBT modules, which in turn improves the reliability and lifetime of the devices.

关键词： Insulated gate bipolar transistors   Junctions   Temperature measurement   Voltage   Long short term memory   Temperature sensors   Time series analysis   Insulated-gate bipolar transistor (IGBT)   long short term memory (LSTM)   maximum junction temperature   parameter dependence  

摘要： Accurate junction temperature characterization plays a critical role in the performance as well as reliability enhancement design of Insulated gate bipolar transistor (IGBT) modules. However, most current methods are only focused on predicting the temperature at a specific time rather than tracking its temporal variation. To address this challenging issue, we propose a long short term memory (LSTM) neural network-based method for predicting the junction temperature time series of IGBTs, and it can comprehensively characterize the time-dependent junction temperature according to the measured and validated experimental results. As the convolutional neural network is limited in its ability to remember temporal information, we integrate the LSTM networks for training, which can fast capture long-time dependencies in the data. Therefore, we exploit the superior performance of LSTM network for predicting the junction temperature of IGBTs here. It is shown that there is a strong correlation between the maximum junction temperature of IGBT and its parameters, such as bus voltage, load current, carrier, and output frequencies, as well as its heat sink parameters. By leveraging the LSTM-based method, an accurate time series information of the junction temperature is successfully captured under different operating conditions. Notably, in comparison with the current machine learning method, the proposed method can outperform in the same training dataset.

关键词： Insulated gate bipolar transistor (IGBT)   Switching loss (ESW)   Forward conduction voltage (VON)   Breakdown voltage (BV)   Super junction  

摘要： In order to further reduce the switching loss (ESW), a novel floating CS layer and super-junction insulated gate bipolar transistor (FCS-SJBJ-IGBT) with internal barrier junction is proposed and simulated. On the premise of not affecting breakdown voltage (BV), the CS layer of FCS-SJBJ-IGBT is floating, so that the P-body is connected with the P-drift region, and a small part of P-pillar is formed between the CS layer and the left gate, which enables electrons to flow rapidly through this region in the on state, and provides an extraction hole path in the off state to reduce the loss. The simulation results show that,under the same forward conduction voltage (VON) condition, the turn-on energy loss (EON) of FCS-SJBJ-IGBT is significantly lower than that of the traditional superjunction IGBT (con-SJ-IGBT) and 34.5 % lower than that of the recently reported super-junction IGBT (SJBJIGBT) with blocking junction, P-pillar and N-pillar, while their turn-off energy loss (EOFF) is almost the same. The research results can provide important reference for reducing the ESW of IGBT.

关键词： silicon carbide   SiC   IGBT   NPC   rectifier   switching   telco   data center   softstart  

摘要： This study presents a novel topology designed to enhance the energy efficiency and quality of IGBT-based high-frequency rectifiers, which are commonly used to supply the high DC power required in industrial applications. In the proposed design, traditional silicon semiconductors are replaced with advanced SiC semiconductors, resulting in reduced switching losses and improved energy quality due to higher frequency switching. The new topology also offers solutions to challenges such as inrush current, reverse energy flow, and high DC output voltage issues typically encountered in IGBT-based rectifiers. The goal is for this topology to maximize efficiency and applicability. The proposed design is simulated in the Simulink environment, with the results presented in the findings section. To highlight the advantages of the new topology, the electrical parameters of the widely used three-phase full-bridge IGBT rectifier topology are employed for comparison.

关键词： Insulated gate bipolar transistor (IGBT)   integrator   junction temperature   maximum collector current falling rate (di(c)/dt(max))   printed circuit board (PCB) Rogowski coil  

摘要： Monitoring the junction temperature T-j of insulated gate bipolar transistor modules is crucial for reliable operation in medium/high voltage applications. Among the various temperature-sensitive electrical parameters, the maximum collector current falling rate di(C)/dt(max) is an effective indicator characterized by excellent linearity and amenability to real-time detection. However, current acquisition methods are prone to introduce parasitic parameters, and di(C)/dt(max) is also affected by the load current i(load). In response to these challenges, the printed circuit board Rogowski coil is proposed to measure di(C)/dt(max) and i(load), which can decouple the effect of i(load), and this method has the advantage of being contactless and integratable. In this article, the dependence of di(C)/dt(max) on T-j and i(load) is theoretically analyzed. The system design of the Rogowski coil current sensor, including coil structure, integrator, and peak detection circuit is carried out. The effective bandwidth and measurement accuracy of the sensor are verified based on the vector network analyzer and the double pulse test, and the effectiveness of the method for T-j estimation is verified based on the buck converter.