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关键词： 滑移转向   轨迹跟踪   LQR算法   前馈控制   最优控制  

摘要： 针对滑移转向车辆构型的无人车,通过建立车辆动力学和运动学模型,对LQR(linear quadratic regulator)最优控制算法进行改进,在速度环采用一种自抗滑移的前馈控制,设计了一种轨迹跟踪控制策略。前馈控制有效提高了横摆角速度响应速度,可进一步优化LQR估计器的参数矩阵,保证车辆在提高轨迹跟踪控制精度的同时不影响跟随稳定性。采用Trucksim与Simulink联合仿真进行验证,结果表明:在双移线测试工况下,使用该控制策略的无人车最大横向误差比在双PID控制下小0.086 m,误差收敛速度2.1 s,稳态误差振荡幅值比滑模控制小约0.05 m;不同车速和不同附着系数路面下,无人车最大横向误差浮动小于0.02 m,误差收敛速度不变,设计算法控制效果稳定,验证了其鲁棒性。

关键词： IGBT   oscillation   solid-state circuit breaker  

摘要： Power semiconductors need to momentarily operate in the active area of DC solid-state circuit breakers (DC-SSCB) to limit the fault current. During this interval, a severe voltage oscillation is observed, leading to the DC-SSCB overstress and eventually failure. This article aims to understand the mechanism causing the voltage oscillation and devise solutions to suppress it. First, a MATLAB/Simulink model is built with comprehensive considerations of power semiconductors, parasitics, gate drive, and metal oxide varistor (MOV). Then a sensitivity study is performed to identify the critical impact factor(s) causing the voltage oscillation. Afterward, three suppression methods using enhanced gate drive circuitry are proposed and compared. Finally, test results based on a 2 kV/1 kA SSCB prototype demonstrate the accuracy of the derived model and the effectiveness of the proposed oscillation mitigation methods.

关键词： superjunction   RC-IGBT   snapback   Schottky contact  

摘要： This paper explores the operation mechanism of the superjunction structure in RC-IGBTs based on carrier distribution and analyzes the advantages and challenges associated with its application in RC-IGBTs for the first time. A Partial Schottky Collector Superjunction Reverse Conduction IGBT (PSC-SJ-RC-IGBT) is proposed to address these issues. The new structure eliminates the snapback phenomenon. Furthermore, by leveraging the unipolar conduction of the Schottky diode and its fast turn-off characteristics, the proposed device significantly reduces the turn-off power consumption and reverse recovery charge. With medium pillar doping concentration, the turn-off loss of the PSC-SJ-RC-IGBT decreases by 54.1% compared to conventional superjunction RC-IGBT, while the reverse recovery charge is reduced by 52.6%.

关键词： Discrete Wavelet Transform (DWT)   IGBT   Photovoltaic (PV) array   Voltage Source Converter (VSC)  

摘要： The power electronic converters have drawn a lot of attention from investigators in recent years. Modern power electronics converters rely heavily on insulated gate bipolar transistors (IGBT). Conventional distribution systems may be made more reliable, stable, and secure by using a microgrid (MG). An acceptable, enticing, and useful option for power distribution networks is inverter-based MGs. This article describes a method for identifying the IGBT switch breakdown failure (IBDF) in a 3-phase, 3-level Voltage Source Converter (VSC) linked to the photovoltaic (PV) grid. The VSC's output phase voltage was subjected to an analysis based on the Discrete Wavelet Transform (DWT) methodology. Kurtosis, skewness, and root-mean-square (RMS) values of the wavelet coefficients of the output phase voltage harmonic spectra of the VSC are all factored in during studies. For the detection of IBDF, comparative learning has been used to identify the specific parameter that is most suitable. Moreover, the comparative analysis and unique contribution of this investigation have been demonstrated.

关键词： Oscillators   Multichip modules   Insulated gate bipolar transistors   Capacitance   Inductance   Switches   Logic gates   Forced oscillation   multichip power modules   multiport network   suppression method  

摘要： In this article, a multiport network approach is proposed to analyze the forced oscillations issue for the multichips power module. First, experimental results indicate the presence of multiple resonance points caused by forced oscillations during the switching process of multichip power modules. Due to the complex distribution of parasitic parameters within the module, it is challenging to establish an accurate analytical model. Therefore, this article proposes a method based on multisoftware collaborative simulation to extract the corresponding impedance of different chip ports. In addition, the impact of bus parasitic inductance and chip capacitances on port impedance is obtained. Compared with the experimental result, the error of dominant frequency obtained by the proposed model is less than 3%. Furthermore, the sensitivity of the spatial near-field spectrum to bus voltage and load current is studied based on experimental results. Finally, the suppression methods for forced oscillations are proposed based on the aforementioned theoretical analysis from the perspectives of both chips and packaging. The effectiveness of proposed methods is verified through experimental results.

关键词： Active filtering   depth-first search (DFS)   field-programmable gate array   model predictive control   partial load efficiency   power electronic converter   silicon carbide (SiC) MOSFETs  

摘要： This article investigates the design and control of the parallel-hybrid converter (PHC), which consists of parallel connection of a silicon insulated gate bipolar transistor (IGBT) bridge and a partially rated silicon carbide (SiC) MOSFETs bridge with a shared dc bus. The IGBT bridge processes the bulk of the power, while switching at a low frequency to maximize efficiency, while the SiC MOSFETs bridge's lower relative switching loss is exploited to filter low-order harmonics from the IGBT bridge. A finite-set model predictive controller is detailed that allows IGBT switching frequencies down to 1 kHz to be achieved while also tightly controlling the magnitude of current in the SiC bridge. A genetic algorithm is utilized to automatically tune the control and investigate the design of the output filter as well as the influence of the controller time-step and horizon length on the performance. Power loss estimates of a 1.5MWapplication case are made showing potential for significant power-loss reductions. Experimental tests validate an field-programmable gate array (FPGA) implementation of the controller and topologies performance, with IGBT bridge frequencies below 1.2 kHz and grid-current total harmonic distortion below 3% achieved. The ability of converter to switch operation between a high-current and a low-current mode and dynamic performance is also verified.

关键词： High-speed train IGBT   Dry ice particles   Spray cooling   Heat sink  

摘要： Aiming at the high efficiency cooling problem of IGBT(Insulated Gate Bipolar Transistor) module of traction converter for high-speed Train, a method of spray cooling with natural dry ice particles was proposed. The heat sinks with pin-fin and straight-fin structure were designed, and the heat sinks with optimum structure size selected by simulation were developed, and the heat sinks were provided with visual shells, as well as single outlet, double outlet and four outlet of the three different ways of outlet. The gas-solid two-phase flow, heat and mass transfer characteristics of dry ice particles in the heat sinks were studied by means of simulation and experiment. By comparison, it is found that the flow and heat transfer in the pin-fin heat sink have a good cooperation, and it is most suitable for the IGBT module with spray cooling of dry ice particles, which can reduce the temperature of IGBT from 70 degree celsius to 55 degree celsius in 75 s, compared with the fin-free heat sink, the heat transfer performance is improved by 12 %, and the double-outlet pin-fin heat sink has the best effect, the temperature difference of the heat transfer substrate is 19.8 degree celsius, and the average temperature of the heat transfer substrate is only 22.5 degree celsius compared with that of the open type, which is 27.3 degree celsius lower. Double outlet dry ice particles spray pin-fin heat sink is an efficient heat sink, thermal resistance is only 0.066 K/W, it can meet the current practical application of high-speed train cooling needs, solve the problem of heat dissipation of IGBT module for high-speed train, it lays a foundation for the development of dry ice particles spray heat sink.

关键词： IGBT   Extended polysilicon gate   Electron inverse accumulation   Forward voltage drop(VCE(sat))   Turn-off loss(Eoff)  

摘要： This paper proposed a Insulated Gate Bipolar Transistor with extended polysilicon gate structure (EPG IGBT) based on P-type drift region (P-Drift), which has electron inverse and accumulation layer. It designs the gate as an extended gate structure with a Bipolar Junction Transistor (BJT), extending into the collector region, and the BJT is always blocked during the switching process. When the EPG IGBT is conducting, the Nj region has a constant positive voltage, which causes the P-Drift to form an electron inversion layer and conduct. Through TCAD simulation, the EPG IGBT maintained the same Breakdown Voltage and turn-off time, while reducing its forward voltage drop (VCE(sat) = 0.98 V) and turn-off loss (Eoff = 0.89 mJ/cm2) by 36 % and 44 %, respectively, compared with FSSJ IGBT of the same process (VCE(sat) = 1.53 V, Eoff = 1.58 mJ/cm2). In addition, the static latch-up I-V and Forward Biased Safe Operating Area (FBSOA) of the EPG IGBT have been significantly improved, providing a new approach for optimizing IGBT.

关键词： Insulated gate bipolar transistors   Interference   Aging   Monitoring   Fatigue   Buck converters   Switches   Aging monitoring   common mode (CM) conducted interference   insulated gate bipolar transistor (IGBT)   solder layer   void fatigue  

摘要： Solder voids are one of the most important aging forms of insulated gate bipolar transistor (IGBT) modules. This article presents an online monitoring method of void fatigue in the solder layer of an IGBT module based on common mode (CM) interference signal spectrum. First, the variation law in collector voltage during the switching process of an IGBT module is analyzed. The cause of CM interference signal in the system where the IGBT module is located is studied, and the relationship between solder layer void fraction and CM interference signal is explored. Second, the study examined the influence of the solder layer void fraction on the parasitic parameters of the IGBT module packaging. It was found that the inductance of the solder layer of the IGBT chip increases with the increase in void fraction of the solder layer, reducing the amplitude of CM interference signals. Finally, taking the buck converter composed of an IGBT module as the tested object, the CM interference signals of IGBT modules with different void fraction are measured, and the void fatigue of the solder layer of an IGBT module is monitored online. The experimental results show that, compared with the healthy IGBT module, the amplitude of CM interference signal decreases with an increase in void fraction.

关键词： Epoxy resin   Electromagnetic wave absorption   Heat conduction   Electronic packaging material  

摘要： Insulated-Gate Bipolar Transistors (IGBT) face limitations in high-frequency electronic applications due to heat accumulation and electromagnetic interference issues. To address these challenges, it is crucial to develop packing materials with excellent electromagnetic interference immunity and heat dissipation properties. In this research, a novel epoxy-based packing material (MDCF@C-ZrO2/EP) with high electromagnetic wave absorption and exceptional thermal transport properties was produced by employing a unique three-dimensional carbon structure-induced nanomaterial dispersion strategy. In particular, the three-dimensional MDCF structure effectively prevents packing agglomeration and fosters the formation of an abundant hetero-interface between MDCF and C-ZrO2, leading to improved impedance matching and enhanced electromagnetic wave dissipation capabilities. Remarkably, even at a mere 5 wt% filling level, the material demonstrates an impressive reflection loss value of -58.92 dB and a wide effective absorption bandwidth of 6.68 GHz, effectively covering the entire Ku-band. Additionally, the 3D MDCF@C-ZrO2 significantly enhances the phonon transport path and elevates the thermal conductivity of pure epoxy resin by an impressive similar to 150%. As a result, this innovative research holds tremendous potential in enabling the application of IGBTs in high-power and high-frequency electronic components, while also contributing to the advancement of next-generation wireless communications and smart devices.