wattful

Based on the physics meaning of reactive power, this text introduces an exact method of calculating to calculate active power and reactive power, and some wrong concepts existingin calculatingreactive power.

本文从无功的物理意义出发,提出一种精确计算有功和无功的计算方法。

First, this paper lists formula of active power by analyzing the composing of instantaneous power, then discusses the effect of prefilter to electric energy metering, how to measure electric energy in transient condition, and the influence of load type to the conversion of electric energy.

本文首先分析了瞬时功率的构成,得到有功功率的公式,接着探讨了前置滤波器对电能计量的影响、暂态情况下的电能计量问题和用户类型对电能转换的影响,最后对有功计费提出了一些建议。

The measurement method of reactive power in traction substation,which main transformer is impedance-matching balance one,is discussed.

通过理论计算和数字仿真 ,分析了在牵引变电所低压侧用有功表计量无功的误差 ,得到了计量结果较实际值偏大的结论 ,对于牵引变电所无功计量方式的设计和运行有一定的指导作用。

Asynchronous sampling scheme for active power measurement;

有功功率测量的异步采样方法

Soft stop control of high-voltage asynchronous motor based on active power close loop;

基于有功功率闭环的高压异步电机软停控制

The present development status of harmonic current detecting methods are introduced and classified,and a few primary harmonic detecting methods are analyzed and compared such as that based on instantaneous reactive power theory,Fourier transform,active power seperation,neural network and so on.

对基于瞬时无功功率理论、有功分离、傅里叶变换、神经网络、小波分析等原理的几种谐波检测方法进行了介绍,讨论了各种检测方法的优缺点,指出:未来电力系统谐波检测会向智能化、多功能实用化以及高精度、高速度和实时性好等方向发展。

Because load change can lead to active loss change of electric power transformer, we researched the way of economic operation of two transformers having the same capacity.

根据电力变压器负荷变化引起其有功损耗的改变,研究两台容量相同的变压器经济运行方式,通过技术分析及论证,得出两台变压器在负荷、容量相同下,若其参数不同,则其损耗不同,在负荷不超出30%变压器容量时,用一台变压器运行比两台变压器并列运行经济,能减少有功损耗,使电力系统经常处于经济运行方式,将变压器电能损失降为最低。