有限元方法分析干式变压器类产品噪声异常的若干问题探讨

简要地探讨了试图用有限元方法计算干式变压器振动和空腔模态来解决噪声异常存在的相关问题,结合自己过去在这方面的工作实践给出了一些大体的方案。     

一体化教学模式在电机与变压器课程教学中的应用

为了提高教学质量和培养高素质人才,运用一体化教学法进行电机与变压器课程的教学。重新修订课程的教学目标和计划,采用多种形式的教学手段和注重实操教学来组织和实施电机与变压器课程的一体化教学。     

以最小二乘法直线度评定食品中砷测定的不确定度分析

目的:以最小二乘法直线度评定食品中砷测定过程中存在的不确定度,并找出影响不确定度的因素较大的环节。方法:根据GB/T 5009.11-2003《食品中总砷及无机砷的测定》的方法,应用最小二乘法拟合直线,进行不确定度评估,并计算出合成不确定度。结果:各分量中工作曲线变动性、移液管、样品定容过程及测量重复性引入的不确定度贡献较大,相对扩展不确定度为U=2.5%(k=2)。结论:以最小二乘法直线度评定食品中砷的不确定度,提高了评定的可信度,通过实验各环节的分析,要求操作过程必须细心、准确、规范,尽量减少不确定度。     

油浸式电流互感器局部放电故障实例分析

结合辽宁电力有限公司某变电站油浸式电流互感器局部放电的故障实例,对该设备结构、故障情况、试验数据和解体检查等方面进行阐述和分析,得出导致此次局部放电的原因是绝缘受潮的结论。最后,对电流互感器的制造工艺和检测方法提出了具体建议。     

Using action research to improve health and the work environment for 3500 municipal bus drivers

During the past five decades occupational researchers have documented that bus drivers’ health is worse than in almost any other profession. The authors suggest that the reason there has not been any successful attempt to change this situation is because the focus until now on removing statistically associated external risk factors has been too narrow. The article describes a project whose purpose was to improve the health and well‐being of 3500 Copenhagen bus drivers. At the end, more than 200 interventions were implemented. The authors adopted a new approach of combining epidemiological results and qualitative methodologies, creating a broader explanatory foundation for action, linked by repetitive processes of critical reflection, which was central to defining problems, explaining causes, developing sufficiently effective interventions and measuring effects. The project revealed the importance of several new and potentially preventable factors involving such issues as lifestyle, private stressors and inappropriate management. During the project period an evaluative framework was developed to explore and measure the complex effects of multiple interventions. Three years after the interventions were launched, follow‐ups revealed remarkable improvements such as reductions in stress and body pains, an increase in satisfaction, and improvements in management and the drivers’ cabin. This article is the story of a methodological journey, from classical epidemiology to an approach combining the strengths of survey (broad coverage), qualitative methods (in‐depth focus) followed by critical reflections and ending with action research.     

两种示波器用多路转换器的设计

本探讨了示波器用多路转换器的基本设计思想,并采用目前在家用电器和其它电子设备上广泛采用的几种集成电路（IC）设计出两种新型、简单、可靠的多路转换器,使示波器可同时显示电信号的路数大为扩展。     

一种新型的光学组合互感器

基于电光晶体的Ｐｏｃｋｅｌｓ效应和磁光玻璃的Ｆａｒａｄａｙ效应,研制出一种新型的可同时测量高压输电线电流及电压的组合互感器。这种互感器绝缘结构简单,电压测量与电流测量是无相互干扰。实验表明,此互感器的非线性误差小于０．３％,电压传感器的转换比在２４℃～３３℃温度范围２４小时的波动在±０．３％以内。     

高频调谐回路引入两种变压器模型后的品质因数计算

引入新的变压器模型后品质因数的计算及表示方法 .     

浅谈变压器分接头的合理选择

本文以保证电力系统末端用电设备的正常工作为出发点,针对系统在最大负荷和最小负荷的两种运行情况,从理论上分析和探讨了变压器分接头的合理选择方法,并用示例进行了计算方法的说明,对选择后的电压水平进行了总结和验证。     

电流互感器二次开路分析及对策

分析了电流互感器(CT)二次开路的原因及其处理和防范措施。