无功的

A new harmonic harmonic and reactive current detection method and a harmonic current detection method base on bandpass filter are introduced in this thesis.

提出两种新的检测方法，检测谐波及无功电流的改进算法和只检测谐波的基于数字带通滤波的检测算法。

ABSTRACT With the development of the ultra-high-voltage power systems and the power supply cables in cities, the charging imaginary power of the high-tension bus bar has become the key problem of the power systems.

随着超高压电网的发展和城市市区供电电缆的增加，高压线路上的充电无功功率已成为电网运行的主要问题之一。

In order to avoid the negative impacts from islanding operation, a novel islanding detection method based on Power Controlling is presented in this paper, The method continuously perturbs the reactive power supplied by dispersed generation systems while simultaneously monitoring the point of common coupling voltage and frequency.

为了避免分布式发电系统在孤岛情况下运行，本文提出了一种基于功率控制的孤岛检测方法，这种方法使分布发电系统提供不断变化的无功功率，同时检测公用连接点的电压和频率。

In this paper, a shunt APF topology with cascade multilevel converter based on Carrier Phase Shifted PWM is presented. The systematic analysis of the harmonic and reactive power detection, AC side and DC side control, system parameter design and so on is done. The simulation study is carried out.imulation shows the APF system is of fast dynamic response and good compensation. Theory analysis and experimental system is feasible..

因此，本文将二者结合起来，提出了基于载波相移PWM技术的级联型多电平变流器并联APF系统的电路拓扑结构，并在谐波及无功检测、交直流控制策略和系统参数设计等方面进行了系统的分析，在此基础上进行了仿真研究。

To detect the harmonic and reactive power current of four-phase transmission system, the current detection method for four-phase transmission system is presented based on FBD method, which is on the basis of improving the FBD method definitions.

为了检测四相输电系统中的谐波和无功电流，在进一步完善FBD法定义的基础上，提出了一种基于FBD法的四相输电系统电流检测方法。

The author made a simulation model in Matlab/Simulink, and did simulation in several conditions such as no load, integrating with power grid, independently modulation of the active and reactive power and capture of the maximum wind power. The simulation results show that analysis is right and have very important guidance signification on experimental systems.

在此基础上，以Matlab/Simulink为工具，建立了系统仿真模型，进行了发电机空载运行、并网、有功、无功功率独立调节、最大风能捕获运行等工况的仿真研究，仿真结果证明理论分析正确，对系统的实验研究具有一定的理论指导意义。

The results indicate the validity and effectiveness of this method in improving voltage quality and minimizing line loss.

另一方面，无功优化在焦作电网的成功应用将大大提高焦作电网的运行电压质量和降低运行网损，势必带来显著的经济效益和社会效益。

The proposed method can effectively reduce line loss and investment of reactive power compensation in power grids, improve voltage quality and operation benefits.

该方法可以有效地改变中国电网线损率高的现状，提高电网无功补偿的投资效益，有利于提高电网电压质量和运行的经济效益。

Reactive power needs depend on the voltage gradient, which is a function of the network topology.

所需的无功取决于电压的增减率，其是网络拓扑的函数。

Effective reactive source placement patterns that were characterized by stability and security improvements as well as transmission loss reduction.

对每一系统，EXEP技术都提出了相应的可提高电压稳定性、安全性并减小网损的、经济合理的无功电源配置方案。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷