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关键词： Torque   Voltage control   Stators   Inverters   Control systems   Torque measurement   Switches  

摘要： Due to the battery voltage performance of the dual power supply open-winding permanent magnet synchronous motor (OW-PMSM) system in electric vehicles, the dc bus voltages of the dual power supply varies and the traditional direct torque control (DTC) method will not be suitable and may lead to obvious torque ripples. Thus, in this article, based on the analysis of the effect of voltage vector on torque variation, a bus voltage ratio is employed in the switching table optimization strategy of DTC for OW-PMSM, the voltage vector selection method is also modified according to different voltage ratio, and then, the optimized control scheme for OW-PMSM over a wide bus voltage ratio is achieved to diminish the torque ripples. Finally, simulation models of the proposed method are built to verify the theory, and the corresponding experiments are also conducted to verify the feasibility and effectiveness of the proposed optimized control strategy.

关键词： Insulated gate bipolar transistors   Logic gates   Delays   Voltage   Semiconductor device measurement   Germanium   Wires   Fault detection   multichip IGBT   partial chip failure   turn-off delay  

摘要： Multichip IGBT module has been widely used in high-power converters. Detecting the status of the IGBT chip is a cost-effective approach to improving the reliability of power devices. This article proposes a novel method based on turn-off delay time to detect chip fault in multichip IGBT modules. First, the effect of chip failure on the turn-off process is analyzed, which causes a decrease in turn-off delay time. Then, a detection method of chip failure based on turn-off delay is proposed, which is validated by experimental results. Furthermore, the effects of chip failure on turn-off delay time in different working conditions are investigated through effective experimental results. The tested results show that the proposed method not only has high linearity and sensitivity to chip failure, but can also eliminate the influence of working environments on detection. The proposed method can be used to monitor the health status of multichip modules and is of great significance for enhancing operation reliability.

关键词： 触摸屏  

ISBN: (纸本)9787122409935

摘要： 本书是辽宁省高水平职业院校和高水平专业群项目建设的成果，是多年校企深度融合的结晶，结合作者多年的高等职业教育教学经验，以装备制造行业、自动化相关企业岗位的实际技术需要为目标进行编写。全书共5章，分别介绍PowerFlex520系列变频器、高速计数器、旋转编码器、PanelView800系列图形终端（工业触摸屏）等基本知识，以Micro850控制器为核心，以变频器、2711R-T7T工业触摸屏、旋转编码器等为执行电器，结合滚珠丝杠和温度风冷等典型被控对象，重点培养学生的PLC程序设计能力、变频器与工业触摸屏的应用能力、学生在生产实际中解决问题的工程能力。本书为高等职业院校相应课程的教材，可作为开放大学、成人教育、自学考试、中职学校和培训机构的教材，以及工程技术人员的参考工具书。本书配有免费的项目实践操作视频、所有项目实践CCW软件环境下的梯形图源程序、电子课件和习题参考答案，请有需要的读者联系化学工业出版社进行获取。

关键词： IGBT device   1/f noise   variational mode decomposition   particle swarm optimization   wavelet threshold denoising  

摘要： The generation of 1/f noise is closely related to the quality defects of IGBT devices. In the process of detecting single-tube noise of IGBT, thermal noise and shot noise show obvious white noise characteristics in the low-frequency range. This paper investigates how to accurately detect the 1/f noise under strong white noise, and thus proposes a particle swarm optimization method known as variational mode decomposition. First, the particle swarm optimization algorithm was used twice to search the optimal parameter combination between the penalty parameter and the decomposition modulus of the VMD model. Then, the parameters of the variational mode decomposition algorithm were set in optimal parameter combination. The frequency center and bandwidth of each IMF component were determined by continuous iteration in the variational framework. Finally, the 1/f noise signal was adaptively separated from background noise. Extensive experimental investigations carried out under different signal-to-noise ratios, compared with the optimal wavelet denoising algorithm, revealed that the PSO-VMD algorithm improved the signal-to-noise ratio by 6.6%, 16.82%, and 42.48%, whereas the mean square error is reduced by 7.12%, 19.80%, and 33.76%.

关键词： acoustic emission   sensor   transducer   gate turn-off thyristor   power electronics  

摘要： The article presents the results of tests related to failure analysis and finding ways to diagnose used semiconductor elements, among others, in power electronics converter systems on vessels and offshore facilities (drilling and production rigs and wind turbines). Diagnostic relationships were found between the temperature change in the above systems and the signals generated in the form of elastic waves of acoustic emission. The authors confirmed the influence of the transistor's working temperature on its amplitude-frequency spectrum of acoustic emission signals emitted. The range of 'safe temperatures' was considered which means temperatures that do not directly affect the damage of the component.

关键词： 变频器   伺服系统   步进电机  

ISBN: (纸本)9787121433580

摘要： 本书介绍了变频器、伺服电机与伺服驱动器、步进电机与步进驱动器应用技术，主要内容有变频调速与变频器，变频器的操作使用与参数设置，变频器的应用电路，PLC与变频器的综合应用，变频器的选用、安装与维护，伺服电机与伺服驱动器，伺服驱动器的硬件介绍，伺服驱动器的操作使用与参数设置，PLC与伺服驱动器的综合应用，步进电机与步进驱动器，PLC与步进驱动器的综合应用，变频器的电路原理与检修。

关键词： Insulated gate bipolar transistors   Transient analysis   Modulation   Buildings   Logic gates   Junctions   Digital-analog conversion   Dynamic electric field modulation   fast turn-off   IGBT   low loss   P-drift (PD) region  

摘要： This article studies the underlying physical mechanism and comprehensive characteristics of the N-channel IGBT (N-IGBT) with P-drift region (PD-IGBT). Distinguishing from the conventional N-IGBT with N-drift region (ND-IGBT), the main blocking junction ( $J_{MB}$ ) of the PD-IGBT is changed from the emitter side to the collector side, which leads to a significant enhancement effect of dynamic electric field modulation. Based on the effect, the PD-IGBT features fast dynamic electric field (E-field) building speed in the drift region and a high E-field at the edge of the field-stop (FS) layer, which can extract excess carriers stored in the device rapidly during the turn-off transient, thus reducing the turn-off loss ( $E_{{off}}$ ) and turn-off time ( $t_{{off}}$ ) of the device. Moreover, the change of $J_{MB}$ location can also alleviate the E-field crowding phenomenon at the trench gate corner, thus providing an optimized relationship between breakdown voltage (BV) and on-state voltage, as well as high avalanche energy. Simulation results show that, when compared with the state-of-the-art N-channel ND-IGBT, the PD-IGBT offers 46% shorter $t_{{off}}$ , 57% lower $E_{{off}}$ , and 60% larger avalanche energy without compromising other device characteristics.

标准号: DL/T 2475.1-2022

摘要： 本文件规定了低压变频器电压暂降及短时中断耐受能力的测试条件、测试布置及设备要求、测试方法等。本文件适用于额定电压交流1000V及以下变须器的电压暂降及短时中断耐受能力测试，其他低压变流器的测试可参考执行。