基于多回路－有限元耦合数学模型的同步发电机定子单相接地故障保护方案校验方法

同步发电机数学模型是进行故障暂态仿真，设计、校验保护方案的理论基础。文中将多回路方法与电磁场有限元计算相结合，建立了同步发电机的多回路一有限元耦合数学模型，其突出优点在于：可以同时计及定子绕组对地分布电容，磁路饱和、磁极形状、齿槽效应等因素，适用于同步发电机定子单相接地故障暂态分析及保护方案(尤其是三次谐波电压保护方案)校验。应用该数学模型完成了同步发电机定子单相接地故障暂态数字仿真，仿真与实验结果基本吻合，验证了该数学模型的准确性与有效性。进而提出了基于多回路一有限元耦合数学模型的同步发电机定子单相接地故障三次谐波电压保护方案校验方法。应用该方法对典型的定子单相接地稳态判据、暂态判据进行仿真校验，结果与实验基本吻合，表明该方法是正确可行的。     

基于定子线圈探测的转子匝间短路故障识别方法

该文通过对汽轮发电机转子线圈匝间短路时的电磁特性进行分析和计算，提出转子绕组匝间短路时，转子绕组主磁场变化比漏磁场明显，用定子线圈作为探测故障线圈，确立了转子绕组匝间短路故障程度和有效磁场损失之间的对应关系：提出转子匝间短路导致发电机定子绕组并联支路之间出现了电势差和环流，其大小和分布与短路严重程度有一定对应关系；利用动模试验机组进行了有关的验证，试验结果和理论推导相吻合。     

高压交流电机定子超薄型绝缘工艺研究

通过对高压电机定子绝缘结构进行分析,以薄型云母带、少胶粉云母带绕包绕组线,构成定子线圈绝缘。定子绕组整体VPI浸渍无溶剂环氧酸酐浸渍树脂的超薄型绝缘系统,实现了高压交流电机定子绝缘的整体减薄。以6kV级电机为例,定子线圈单边主绝缘厚度由常规型的1．4mm减薄到小于1mm。     

An improved low-voltage ride-through performance of DFIG based wind plant using stator dynamic composite fault current limiter

In this paper, an enhanced low-voltage ride-through (LVRT) performance of a grid connected doubly fed induction generator (DFIG) has been presented with the usage of stator dynamic composite fault current limiter (SDCFCL). This protection circuit comprises of a suitable series resistor–inductor combination and parallel bidirectional semiconductor switch. The SDCFCL facilitates double benefits such as reduction of rotor induced open circuit voltage due to increased value of stator total inductance and concurrent increase of rotor impedance. Both effects will limit rotor circuit over current and over voltage situation more secured way in comparison to the conventional scheme like the dynamic rotor current limiter (RCL) during any type of fault situation. The proposed concept is validated through the simulation study of the grid integrated 2.0 MW DFIG.     

交流永磁伺服电机关键加工工艺研究

研究设计出交流永磁伺服电机转子磁钢粘结、定子的加工与焊接及定转子装配的加工方法及工艺装置。论证了这些工艺方法的设计依据及可靠性,通过实际生产中的应用,证实了设计的工艺方法是先进合理、切实可行的。完全可以保证伺服电机的产品质量,并适用于伺服电机的系列化研究和批量生产。     

Utilizing cable winding and industrial robots to facilitate the manufacturing of electric machines

Cable wound electric machines are used mainly for high voltage and direct-drive applications. They can be found in areas such as wind power, hydropower, wave power and high-voltage motors. Compared to conventional winding techniques, cable winding includes fewer manufacturing steps and is therefore likely to be better suited for automated production. Automation of the cable winding production step is a crucial task in order to lower the manufacturing costs of these machines. This article presents a production method using industrial robots for automation of cable winding of electric machine stators. The concept presented is validated through computer simulations and full-scale winding experiments, including a constructed robot-held cable feeder tool prototype. A cable wound linear stator section of an Uppsala University Wave Energy Converter and its winding process is used as a reference in this article. From this example, it is shown that considerable production cycle time and manufacturing cost savings can be anticipated compared to manual winding. The suggested automation method is very flexible. It can be used for the production of cable wound stators with different shapes and sizes, for different cable dimensions and with different winding patterns.     

Decision fusion system for fault diagnosis of elevator traction machine

Fault detection and diagnosis is critical for healthy operation of an elevator system. In order to realize a real-time and convenient diagnosis and satisfy the requirement of advanced maintenance of an elevator system, this paper proposes an intelligent fault diagnosis approach of induction motor for elevator traction machine using a developed decision fusion system. First, the basic knowledge of fusion techniques is briefly introduced which consists of classifier selection and decision fusion. Then a developed decision fusion system is presented. Next, four fusion algorithms—majority voting, Bayesian belief, multi-agent and modified Borda count—are employed for comparison in a real-world diagnosis experiment of a faulty elevator motor system. Based on the satisfactory results shown in the experiment, a big potential in real-world application is presented that is effective and cost saving only by analyzing stator current signals using proposed decision fusion system.     

基于DSP三相异步电动机故障在线监测的研究

DSP具有高速时钟频率和快速的运算速度,为故障在线监测提供了硬件支持。本文通过定子视在阻抗的分析,发挥DSP的数据处理能力,实现了对三相异步电动机故障的在线监测。     

单螺杆泵定子修复装置设计

依据单螺杆泵机构构成及运动规律，设计了一种结构简单、工作可靠、造价低廉的新型定子修复装置，并介绍了其工作原理和结构特点。     

直接转矩控制系统定子电阻观测的研究

目前直接转矩控制系统是控制感应电动机的一种新兴技术,它不需要复杂的控制算法就可以得到异步电动机的磁链和转矩．但是感应电动机定子电阻的变化影响直接转矩控制系统的低速性能,因此调节电动机的定子电阻是非常重要的．本文综述了直接转矩控制系统定子电阻观测方法的研究现状,阐述了定子电阻不同的观测方法,并展望了直接转矩控制技术的应用前景．