一种新型并联混合有源滤波器的研究

本文提出了一种新型并联混合型有源滤波器的拓扑，新型拓扑通并联谐 振抑制流过无源网络的基波无功电流，减小了有源滤波器承担的基波电流。同时在此拓扑基础上讨论了它的控制策略，在此控制策略下，有源滤波器不承担基波电矿井，且只承担很小的基波电流，因此有源滤波器的容量达到了最小，本文分析了并联谐振对无源网络阻抗的影响，并对此分析了控制策略在传统拓扑和新型拓扑下对有源滤波器容量的影响，最后通过仿真证明了结论的正确性。     

并联型有源电力滤波器的SVPWM控制技术研究

针对有源滤波器常规滞环、三角载波控制时,开关频率波动大,响应慢的缺点,引入了空间电压矢量算法。在K步时,假定K+1步,APF的补偿电流完全跟踪上了谐波指令电流,再根据APF离散的数学模型及空间电压矢量调制模块,确定第K+1步的开关管驱动信号,以达到快速补偿谐波电流的目的。仿真实验表明,基于SVPWM控制的有源滤波器具有开关频率固定,动态响应快,补偿精度高的优点。     

并联型有源电力滤波器直流侧电压柔性控制策略

针对并联型有源电力滤波器的直流侧电压控制特点,提出了一种对直流侧电压进行柔性控制的并联型有源电力滤波器控制策略。该策略中,在直流侧电压控制部分引入反馈低通滤波器,削弱直流侧固有谐波对输出电流控制的影响;在电流控制的输出部分通过增加直流侧电压前馈系数,抵制在变换桥中可能引入的直流侧电压谐波影响。仿真结果表明直流侧电压柔性控制策略能够降低APF系统补偿后的电源电流总谐波畸变率,从而改善并联型有源电力滤波器的谐波补偿性能。     

电阻分流热电流温度补偿技术及应用

电阻分流热电流温度补偿技术及应用是为温度测量 热电偶与补偿导线失配专门研究一切后种新技术，试验与应用证明：它在补偿温度失配误差，减小测量系统的误差，校正起初炉温，改善系统温度响应特性方面都具有非常好的效果。     

Shunt capacitor placement in radial distribution networks considering switching transients decision making approach

This paper provides a new approach in decision making process for shunt capacitor placement in distribution networks. The main core of the evaluation process is a multi-objective framework to allocate the capacitor banks. The power loss and the total harmonic distortion (THD) are the objective functions of the system under study in a long-term planning horizon. In order to select the executive plan introduced by using a multi-objective model, transient switching overvoltages have been considered. As the size and location of shunt capacitors may result in unacceptable overvoltages, the proposed technical decision making framework can be applied to avoid corresponding damages. In this paper, an iterative conventional power flow technique is introduced. This technique can be applied to evaluate THD for distribution networks as well as other power flow based objectives, such as power losses calculation and voltage stability assessment. The presented framework is a two stage one where at the first stage, a non-dominated sorting genetic algorithm (NSGA-II) augmented with a local search technique is used in order to solve the addressed multi-objective optimization problem. Then, at the second stage, a decision making support technique is applied to determine the best solution from the obtained Pareto front. In order to evaluate the effectiveness of the proposed method, two benchmarks are addressed in this paper. The first test system is a 9-bus distribution network and the second one is an 85-bus large scale distribution network. The simulation results show that the presented method is satisfactory and consistent with the expectation.     

官亭变电站750 kV高压并联电抗器运行状况分析

官亭变电站750 kV 2#电抗器是国内目前运行电压等级最高的一组高压并联电抗器。分析了750 kV高压电抗器在官亭变电站的运行情况和技术监督数据:技术监督数据稳定,油色谱分析数据良好,继电保护和安全自动装置无动作,电抗器整体运行状况良好。提出了未来改造计划:重新建造3台电抗器的基础,将目前的条形基础改为方形基础,增强电抗器的底部支持面,放弃现在使用的千斤顶;制造一台新的电抗器,替换运行中的电抗器B相。     

Solar cell array parameters

A generalized method of combining non identical parameters like series and shunt resistance dependent photocurrents under open circuit conditions (I_phoa) and the loaded conditions (I_pha) have been deduced. It is found that in the case of series array, only I_pha is dependent upon shunt resistance, while in the case of parallel array both are dependent upon shunt resistance.     

A method for the determination of dynamic resistance of photovoltaic modules under illumination

Dynamic resistance of solar cells and modules have been determined from a dark IV characteristic curve. In the determination, it is often assumed that series resistance R_s is small and the shunt resistance R_sh very large, their effects can be neglected. The resultant dynamic resistance can be called the external dynamic resistance R_D. R_D is normally taken to be the slope of the IV characteristic of a cell or a module. We present in this paper a new method to determine an internal dynamic resistance R_d of a photovoltaic module based on one illuminated IV curve, taken into account finite series and shunt resistance. In the experiment, we measure illuminated and dark characteristics of a 4.5 Wp commercial X-Si solar module (9 V, 500 mA) at 25–27 °C, and calculate R_d and R_D. We see that R_d and R_D can be markedly different. Comparison is also made on the series resistance R_s and shunt resistance R_sh determined from single IV curve and two IV curve methods.     

一种并联有源电力滤波器的复合控制方法研究

在采用并联有源电力滤波器来消除电网谐波时,由于其滤波器的检测精度、指令电流计算延时等原因,一般的控制方法很难达到理想的滤波效果。因此,本文提出了基于常规PI控制和重复控制的复合控制方法,能使系统获得很好的静态性能和动态性能。仿真实验表明,这种控制方法实现相对比较简单,在响应速度和控制精度上都具有一定的优势,且能有效地对...     

干式高压并联电容器的技术特点分析

分析了干式高压并联电容器技术特点，提出了产品结构方面的改进措施和发展方向，就干式高压并联电容器的运行注意事项进行了总结。