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关键词： 变频技术   变频器   皮带机改造   煤矿   电磁兼容  

摘要： 皮带机在应用过程中存在设备损耗率较高、能量消耗较大等问题,容易引发各种事故,需要改造。变频技术在皮带机改造中得到应用。文章介绍变频技术基本情况,分析变频技术在煤矿皮带机改造中的应用要求,就其应用展开探讨。

关键词： Logic gates   Insulated gate bipolar transistors   Voltage   Temperature sensors   Temperature measurement   Monitoring   Junctions   Gate voltage   insulated gate bipolar transistor (IGBT)   monitoring   power semiconductor devices   temperature measurement  

摘要： The junction temperature estimation of the insulated gate bipolar transistor (IGBT) module is crucial for reliability assessment and health management of converters. However, most of the existing methods need to measure the collector-emitter voltage and collector current for the IGBT junction temperature estimation, which increases the cost and complexity of the monitoring and calibration process. In this article, a novel junction temperature monitoring method for IGBT modules without involving operating condition calibration based on the pre-overshoot of gate voltage is proposed. The gate pre-overshoot is influenced by the internal gate resistor, which has a linear relationship with the IGBT junction temperature. Besides, the gate pre-overshoot is only temperature dependent, while not affected by the collector-emitter voltage and collector current. Therefore, the gate pre-overshoot is a promising temperature-sensitive electrical parameter (TSEP). Because the collector-emitter voltage and collector current are not involved, the gate pre-overshoot-based method for junction temperature has the advantages of a simple signal monitoring structure, a simple calculation process, and a simple calibration process.

关键词： ~Automatic optimization   global sensitivity   insulated gate bipolar transistor (IGBT)   parameter extraction   physics-based models  

摘要： The accurate simulation of insulated gate bipolar transistor (IGBT) characteristics is an essential task to predict its electrical behaviors. Numerous physics-based IGBT models have been developed and proven to produce satisfactory simulation results. However, unavailability of device parameters is the key roadblock to the application of these physics-based models. In addition, the coupling between device parameters renders parameter extraction very challenging and heavy. In this article, a novel parameter extraction scheme by switching feature partitioning is proposed, which considerably relaxes the negative impact of parameter coupling during parameter extraction. The IGBT inductive turn-off process and static characteristics are divided into nine typical feature segments under an inductive load. Then, the physical principle of each feature segment is analyzed, and the corresponding influencing parameters of each feature segment are found. During the parameter extraction, the corresponding weights are assigned to the parameter search according to the error of each feature segment. The proposed method for parameter extraction is elaborated. Using the extracted parameters, the simulation results by the physics-based IGBT model are in excellent agreement with the experimental results of the tested IGBT, and the effectiveness of the proposed parameter extraction program is verified. Finally, the extracted parameters are evaluated and verified by global sensitivity analysis.

关键词： junction temperature   electroluminescence   FBG   IGBT   SiC   MOSFET  

摘要： Recent advancements in power electronic switches provide effective control and operational stability of power grid systems. Junction temperature is a crucial parameter of power-switching semiconductor devices, which needs monitoring to facilitate reliable operation and thermal control of power electronics circuits and ensure reliable performance. Over the years, various junction temperature measurement techniques have been developed, engaging both non-optical and optical-based methods, highlighting their advancements and challenges. This review focuses on several optical sensing-based junction temperature measuring techniques used for power-switching devices such as metal-oxide-semiconductor field-effect transistors (MOSFETs) and insulated-gate bipolar transistors (IGBTs). A comprehensive summary of recent developments in infrared camera (IRC), thermal sensitive optical parameter (TSOP), and fiber Bragg grating (FBG) temperature sensing techniques is provided, shedding light on their merits and challenges while providing a few possible future solutions. In addition, calibration methods and remedies for obtaining accurate measurements are discussed, thus providing better insight and directions for future research.

ISBN: (纸本)9787040596458

关键词： Chlorine compounds  

摘要： In this study, the corrosion resistance and electrical and mechanical properties of 20 mil pure copper (Cu) and copper–phosphorus (CP) micro-alloyed wires were investigated. The experimental results show that both wires are equiaxed crystals containing twinning boundaries, and their similar grain sizes result in similar tensile properties and hardness values. In addition, both wires exhibit similar electrical performance characteristics;however, the CP wire has a more stable dynamic resistance and electrothermal impedance. The chloride corrosion tests showed that both wires experience pitting corrosion on the surface;chloride ions mainly corrode the twin boundaries and then the grain boundaries, which delays the corrosion process and prevents the significant degradation of the wire's electrical properties after chlorination. Considering the application of wires in insulated gate bipolar transistors (IGBTs), the wire failure mechanism was evaluated through electrical and mechanical tests, including tests of the electrothermal fatigue mechanism to determine the electrical properties and bending fatigue tests to determine the mechanical properties. When subjected to chloride corrosion, the CP wire has fewer twin boundaries and a lower boundary corrosion resistance, resulting in a better basal effect that improves the corrosion resistance and promotes work hardening during bending. As a result, the CP wire has a longer current cycle life and better bending fatigue properties than the Cu wire. This confirms the excellent application reliability of CP wires subject to corrosion. © 2023 Elsevier Ltd

关键词： Photovoltaic inverter   IGBT reliability   Reactive power regulation   LightGBM model   Distribution network  

摘要： When the PV power supply participates in reactive power regulation of distribution network, its output reactive power will affect the reliability of IGBT in the PV inverter. Aiming at this problem, this paper first qualitatively analyzed the influence of photovoltaic power supply participating in reactive power regulation of distribution network on the reliability of photovoltaic power supply. Then, a quantitative evaluation method of IGBT reliability based on data-driven was proposed. This method uses LightGBM machine learning model to replace the traditional thermoelectric coupling model, which effectively improves the calculation efficiency of IGBT junction temperature and reduces the dependence of IGBT reliability evaluation results on IGBT model parameters. Through this method, the reliability of core power electronic devices in photovoltaic inverters is quantitatively evaluated according to active power, reactive power, solar irradiance and ambient temperature. Finally, based on the IEEE 33 node distribution system, the reliability of IGBT in PV inverters participating in reactive power regulation of the distribution network was evaluated.

关键词： Convolutional neural networks (CNNs)   insulated-gate bipolar transistor (IGBT) modules   junction temperature monitoring (JTM)   load current dependence   turn-OFF voltage (TOV)  

摘要： Junction temperature monitoring (JTM) is essential for reliability evaluation and health management for insulated-gate bipolar transistor (IGBT) modules, and thus is extensively focused on in power electronics converters. However, many JTM methods for IGBT modules are criticized for providing inaccurate junction temperature information with strong load current dependence. To address this, a JTM method based on the turn-OFF voltage (TOV) and convolutional neural networks (CNN) is proposed in this article. In this method, the TOV is used as the junction temperature indicator, and the characterization behavior of the TOV during turn-OFF transient process is thoroughly analyzed. Then, the parameter dependence of the TOV is investigated. Considering the proposed JTM method may be subject to the issue of load current dependence and show an undesirable performance, the CNN is adopted to maintain the accuracy of junction temperature prediction due to its excellent global and local feature recognition capability. With this regards, the proposed JTM method enables to provide accurate junction temperature information under different conditions. Finally, the double-pulse tests and experimental tests are carried out to validate the effectiveness of the proposed JTM method.

关键词： Artificial neural network (ANN)   insulated-gate bipolar transistor (IGBT)   monitoring   power semiconductor devices   reliability   temperature measurement  

摘要： The insulated-gate bipolar transistor (IGBT) junction temperature is crucial for condition monitoring, reliability assessment, and health management. However, the existing IGBT temperature monitoring methods are affected by the aging of IGBT bond wires. A novel junction temperature estimation method independent of bond wire degradation for IGBT is proposed in this article. On-state voltage drop and turn-ON gate voltage overshoot are analyzed for dependence on the junction temperature and bond wire degradation. These two temperature and bond wire monitoring electrical parameters are combined by the artificial neural network, to eliminate the effect of bond wire degradation. A double pulse test platform is built to verify the influence of temperature and bond wire degradation on on-state voltage drop and turn-ON gate voltage overshoot, which agrees with the theoretical analysis. Lots of experimental data at various collector-emitter voltages, load currents, IGBT junction temperature, and bond wire degradation are tested. A BP neural network is trained for junction temperature monitoring and its optimal number of hidden layers is studied. The experimental results show that the junction temperature estimation method based on the neural network can effectively eliminate the effect of bond wire degradation. The estimation error is around 4.219 degrees C. The proposed method has the advantages of high accuracy and a wide application range for junction temperature monitoring.

关键词： IGBT power modules   insulation degradation   partial discharge   electric tree  

摘要： IGBT power modules are usually used as circuit-breaking components in power systems, and are widely used in solid-state DC circuit breakers, hybrid DC circuit breakers, all-electric aircraft, high-speed railways, new energy vehicles, and power transmission systems. In these systems, IGBT power modules are usually faced with extremely harsh working conditions and there is a failure risk. Insulation degradation should be a cause for concern as a potential path of power module failure. In this paper, the discharge phenomena of the IGBT power module were observed based on Intensified Charge Coupled Devices (ICCD), and the triple junctions composed of copper-ceramic-silicone gel inside IGBT were found as the discharge points. Furthermore, the directed bonded copper (DBC) ceramic filled with silicone gel was used as a test sample to study the discharge failure process, including the partial discharge (PD), surface charges, and electric trees. The mechanism of discharge failure is discussed and analyzed. The insulation degradation process is accompanied by phenomena such as severe partial discharge and rapid electric tree growth. This research provides support for the analysis idea and guidance of the research method for the cause of power module failure.