课程文献中心 更多>>

关键词： Turbulence wind speed   IGBT   low-frequency junction temperature fluctuation   linear power control   thermal management strategy  

摘要： Wind speed fluctuation generally shortens the lifetime of the insulated gate bipolar transistor (IGBT) module in the doubly fed induction generator (DFIG), which leads to frequent component replacement and cost increase of wind power generation. Conventional power control strategies consider solely the wind turbine output power maximization, and existing junction temperature thermal management strategies focus on IGBT lifetime extension, both of which are not effective under turbulent wind speed conditions and ignore the trade-off between the device reliability and output power for the overall DFIG economic benefit. To bridge the gap between the IGBT reliability and the output power under turbulent wind speed conditions, we propose a novel IGBT thermal management strategy for optimal economic benefit. Specifically, we first smooth the output power through a linear power control (LPC) method with conditions on the wind speed and turbine speed to reduce the IGBT low-frequency junction temperature fluctuation, which extends IGBT lifetime. We then propose a grid encirclement and suppression search (GESS) method that maximizes the economic benefit defined by LPC-smoothed output power and IGBT lifetime. Simulation shows that our proposed LPC-GESS strategy outperforms a competing strategy at economic benefit by a large margin, up to 15.3%. Our proposed strategy can potentially be used in wind power stations for fast and reliable economic benefit-oriented IGBT thermal management.

关键词： hybrid-switch DC-DC converter   duty-cycle modulation   optimized modulation strategy   switching characteristics   DC solid state transformer  

摘要： The DC solid state transformer (DCSST) is a crucial component for connecting buses of different voltage levels in the DC distribution grid. This paper proposes a Si IGBT/SiC MOSFET hybrid isolated bidirectional DC-DC converter and an optimized modulation strategy (OMS) to reduce the losses and costs of DCSST. Based on the analysis of topology and operating principles, a duty-cycle modulation strategy is proposed and the converter is modeled by the time domain analysis (TDA) method. Through the analysis of switching characteristics, an optimization problem is established, which aims to reduce the conduction losses of switches while ensuring zero-voltage switching (ZVS) for all switches and low-current turn-off for IGBTs simultaneously. The optimization problem is solved by the augmented Lagrangian genetic algorithm (ALGA), and the OMS for the proposed converter is deduced. Finally, a 2 kW experimental prototype with the primary voltage of 405-495 V and the secondary voltage of 150 V is built to verify the effectiveness of the proposed topology and OMS. The switching costs of the proposed converter is reduced by 27.3% and the efficiency is improved by up to 4.04% compared to the existing method.

关键词： Machine learning   bond wire   thermomechanical loading   IGBTs   FEM simulation  

摘要： A Bayesian machine learning (ML) framework was introduced for the comprehensive characterization of bond wires within insulated gate bipolar transistor (IGBT) modules under the influence of thermomechanical loadings. The primary objective of this work was to predict two critical performance metrics, namely, equivalent plastic deformation (EPD) and the number of cycles to failure (Nf). At the core of our investigation was the dependable acquisition of training data via finite element method simulations. Based on the results, exceptional predictive accuracy was achieved, as evidenced by the impressive R-squared values of 0.962 for EPD and 0.927 for Nf, both of which are obtained from the Bayesian ML model. The high performance of the Bayesian model can be attributed to its ability to effectively capture complex relationships within the data while simultaneously being robust in handling uncertainties, rendering it suitable for situations characterized by limited datasets. Furthermore, it was revealed that the weight functions of the input parameters were significantly influenced by the values of the output targets, illustrating the distinct dependencies between each output target (EPD and Nf) and the relevant input features. These findings contribute to a deeper comprehension of the intricate interactions between input parameters and output metrics, ultimately aiding in the development of more precise and dependable models for bond wire characterization in IGBT modules.

关键词： Superjunction insulated gate bipolar transistor   (SJ-IGBT)   Semi-floating P-Pillar   On-state voltage ( V CE(sat) )   Turn-off loss ( E off )   Breakdown voltage  

摘要： -In this paper, a novel dual-trench superjunction insulated gate bipolar transistor with semi-floating P-pillar (DTSFP-SJ-IGBT) is proposed and studied by simulation. The P-pillar of DTSFP-SJ-IGBT is semi-floating because only a portion is located below the trench gate, while a small part remains directly connected to the P-base. This small part P-pillar is depleted by the gate voltage in the on-state to enhance the carrier-storage effect, and provides an extraction hole path in the turning-off state to reduce the loss. The dual-trench structure results in a more uniform electric field distribution within the device while enhancing the carrier storage effect in the pillar regions. The simulation results show that at the same on-state voltage (V-CE(sat)) of 1.30 V, the turn-off loss (E-off) of the DTSFP-SJ-IGBT is 38.46 % lower than that of the superjunction IGBT with floating P-pillar (FP-SJ-IGBT), and 27.93 % lower than that of the recently reported superjunction IGBT with self-adaptive hole-extraction path (SAHE-SJ-IGBT). At the same E-off of 1.00 mJ/cm(2), the V-CE(sat) of the DTSFP-SJ-IGBT is 44.70 % lower than that of the conventional superjunction IGBT (Con-SJ-IGBT).

关键词： Multi-level inverter   Emperor penguin optimization   Deep belief network   Asymmetric   Pulse generation   Reduced switch count   IGBT   Buck-boot converter and DC sources  

摘要： The multi-level inverter (MLI) plays an emergent role in high and medium-power applications. Due to the numerous advantages like lower power loss, switching loss and harmonics, the MLI is used in various applications. The major drawbacks of MLI are a higher number of switches and complex modulation strategies, thus increasing the voltage stress. Therefore, this paper proposed a novel single-phase cascaded 51-level inverter topology with fewer switches and DC sources to improve system performance. In this proposed topology, 8 IGBT switches along with 2 DC voltage sources are considered for producing 51 levels of voltage. This 51-level inverter is tuned with the help of an EPDB controller, which is a combination of Emperor Penguin Optimization (EPO) and Deep Belief Network (DBN). The EPO is used to optimize the DBN procedure to handle the MLI switches easily. Thus, it generates low harmonics voltage and error-free output voltage. The proposed inverter topology is compared with existing inverter topologies regarding the number of voltage sources, switches, and total harmonics distortion (THD). The comparative analysis demonstrates that the suggested inverter topology provides higher voltages, thereby reducing the THD of voltage to 1.17% and current to 0.10%, which are relatively lower than the existing inverter topologies;moreover, the efficiency of the proposed converter is 99.18%.

摘要： 风电、光伏为代表的可再生能源市场快速发展,让SVG、变频器产业迎来黄金发展期. 近年来,在"双碳"背景下,我国可再生能源加快发展,已成为保障我国电力供应的重要力量.国家能源局发布的最新数据显示,2023年我国可再生能源总装机达到14.5亿千瓦,占全国发电总装机超过50％,历史性超过火电装机.截至2023年12月31日,我国可再生能源年内发电量3万亿千瓦时,约占全社会用电量1/3;风电光伏发电量已超过同期城乡居民生活用电量,占全社会用电量比重突破15％.

关键词： Heat sinks  

摘要： The press-pack Insulated Gate Bipolar Transistor(IGBT) is the core power device of high-power electronic equipment and is also widely used in flexible DC transmission projects. In the operation process, the transmission of large currents will produce uneven distributions of electromagnetic loss and force, leading to local point overheating or excessive stress deformation. Therefore, the design of IGBT's heat dissipation is essential. The environment where IGBT heat sinks are located is relatively complex, involving the coupling effect of multiple physical fields such as force, heat, electromagnetic, etc. Based on this, we conduct a decoupling analysis of IGBT heat sinks under multiple physical fields of electromagnetic-thermal-stress and delve into the interaction mechanism between multiple physical fields. The results show that the influence of the thermal stress field on the force field is particularly significant. In contrast, the influence of the electromagnetic field on the multi-physical field is weak. Furthermore, we propose a multi-objective optimization method for the structural parameters of water-cooled radiator channels in electromagnetic-thermal-stress multiple physical fields. We design structural parameters for the flow channel depth and width of IGBT heat sinks. It sets the minimization of thermal and flow resistance of water-cooled radiators as the optimization objective and uses the Kriging method to construct a response surface model. Using the MOGA optimization algorithm, a multi-objective optimization design is carried out on the internal flow channel structure of water-cooled radiators, and the optimal solution is achieved. Finally, an experiment platform is established to verify the optimized design. This paper provides an optimization design method in the multi-physics fields for the structural design of IGBT radiators. © 2024, The Authors. All rights reserved.

关键词： 模糊PI控制   模型预测控制   直接转矩控制   永磁同步发电机   能量回收  

摘要： 在天然气、内燃机所产生的废气和高炉煤气等气体的传输过程中，调压系统需要将气体由高压调节到用户侧的低压状态，其中的压力能可以通过膨胀机带动发电机工作进行回收，此时用户侧压力会受到用气负荷等随机扰动的影响，而由于发电机自身具有非线性，且传统直接转矩控制中滞环比较器与开关表非线性较强，造成控制器设计困难，导致发电机转矩波动较大。为此，设计、开发了气体压力能回收发电控制系统，在发电机转速控制回路设计模糊PI控制器，以实现PI参数自适应整定；同时设计了发电机转矩控制回路模型预测控制器，基于使发电机转矩和磁链稳定的优化目标进行电压矢量计算，以提高控制策略的效率，并通过延时补偿改善控制性能和鲁棒性。搭建气体压力能回收实验平台，利用压缩机调节空气压力模拟气体压力变化，基于上述策略，采用DSP28335设计、开发了气体压力能回收发电控制器。实验结果表明，所提出的控制策略与传统直接转矩控制策略相比，在用户侧压力波动的情况下，发电机转矩和转速波动范围大幅减少，提升了发电质量。

关键词： 峰值电流控制   Boost DC-DC变换器   IGBT   智能驱动   米勒平台  

摘要： 峰值电流控制Boost DC-DC变换器的电流内环需检测IGBT集电极电流，现有的电流检测方法需在IGBT主电路中串入元器件，增加了电路体积和成本，降低了主电路效率。本文基于具有集电极电流检测功能的IGBT智能驱动技术，提出一种无电流传感器的峰值电流控制Boost DC-DC变换器。首先，给出了智能驱动设计，在米勒平台期间集电极电流和栅极电流关系的基础上，提出了三点法用于确定IGBT器件米勒平台期间集电极电流和栅极电流关系，通过检测栅极电流来检测集电极电流；其次，建立了考虑采样保持、量化误差以及延时影响的前缘调制Boost DC-DC变换器小信号模型，对变换器进行了稳定性设计。最后搭建了一台基于驱动侧电流检测的无传感器Boost DC-DC实物样机，验证了电流检测和稳定控制效果。