旋翼式热量表基表设计中应注意的问题

我国政府政策规定新建居住建筑使用热量表作为热计量工具。目前我国自主研发的热量表多为机械式热量表,为获得最佳的热量表性能,在基表设计中应注意选择合适的基表形状、叶轮叶片数目、采用分流片、加装调节肋板等,以满足测量精度的要求。     

Implementation of the shunt harmonic voltages compensation approach

Instead of injecting harmonic currents to compensate those drawn by distorting loads, in this paper a shunt active filter is used for generating harmonic voltages to compensate harmonic voltages at the point of common coupling; the main advantage in using such a compensation approach is that, when the aim is to reduce or eliminate the harmonic voltages at the point of common coupling only one active filter is required. For determining the harmonic voltages such a filter must generate, two simple and practical methods are proposed in this paper; the effectiveness of these methods was evaluated using a 1-kW prototype of an active filter operating according to the shunt harmonic voltage compensation approach. In addition, the laboratory results were comparable to those obtained with the ATP-EMTP simulation software.     

电容装置不平衡保护灵敏系数的取值

从分析影响高压并联电容器装置不平衡保护动作灵敏度的有关因素入手,推出保护灵敏系数与电容装置正常运行时出现的不平衡电压或不平衡电流的关系式及其取值范围,以供工程设计与装置运行参考。     

基于节点电纳摄动的通用配电网损耗分配方法

文中主要探讨配电网损耗的分配方法。针对含有转供和小电源的任意结构配电网，分析并给出了损耗分配的对象和基本要求。提出了一种基于节点电纳摄动改造配电网全节点导纳矩阵可逆性的方法。这种改造方法从损耗分配的合理性与潮流误差出发确定电纳摄动点和摄动值，使任意配电网的全节点阻抗矩阵能够可靠计算。最后基于全节点阻抗矩阵和交易的等值节点电流提出了一种通用的配电网损耗分配方法。这种分配方法既适用任意结构的配电网络和Pool与Bilateral交易，又满足电路定律、具有可加性和聚合不变性的经济特征。仿真结果验证了文中方法的有效性。     

The location of a resistive shunt harmonic impedance along a distribution feeder and its influence on harmonic propagation

Although complete compensation is only possible using true active filters, resistive shunt harmonic impedances (SHI) have been shown to provide a considerable reduction of the harmonic propagation. In this paper, the harmonic mitigation potential of a resistive SHI is discussed concerning its influence on the voltage distortion profile along a typical distribution feeder, with the location of the SHI along the feeder as a parameter. Although the distortion values are dependent on the SHI location, it is shown that the end of the feeder is generally a good location to install the SHI, especially when the power system parameters can vary or are unknown. Calculations are performed on a typical radial distribution feeder. Both the power factor correction capacitors and the non-linear loads are concentrated in single nodes. The linear loads are disconnected to obtain the worst case for the voltage distortion. Also some measurements on a scale model of a typical distribution feeder are done and the experimental results confirm the results obtained from simulations.     

切合并联电容器组暂态过电压问题的研究

采用EMTP电磁暂态程序,考虑在最不利的运行条件下,计算得出切合并联电容器组暂态过电压水平,并给出降低暂态过电压的措施。     

500kV并联电抗器色谱监测与故障诊断

通过对一台 5 0 0kV高压并联电抗器的色谱分析测试 ,分析了造成高压并联电抗器过热的原因 ,介绍了具体的改造方法和改造后的运行状况。     

自动投切电容器装置技术的研究

叙述并联电容器装置分组自动投切的两种分类。介绍了典型的控制策略及实现方式     

并网风电机组补偿电容器投入过程研究

对风电场并联电容器的投入过程进行了仿真研究。着重研究了投入电容器时的高频涌流及过渡电压降低的现象并提出了有效的改善措施。     

Prediction of shunt currents in a bipolar electrolyzer stack by difference calculus

A model for predicting shunt/leakage currents in a bipolar electrolyzer stack with dual electrolyte inlets and significant amount of gases in the outlet ports and manifold is presented. Model includes electrolyte, manifold and membrane separator as resistance components in the electric circuit analog of the stack. Activation overvoltage associated with electrodes is taken as Tafel-like. Current balance and potential balance equations are applied to the stack and difference calculus is employed to reduce the problem to a set of linear difference equations with constant coefficients. The model is validated with published results and the effect of each resistance component and number of cells on leakage currents in the stack is presented. The U.S. Goverment’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.