一种基于半波积分的电流幅值算法

次同步过流保护是抽水蓄能机组在变频启动过程中必须设置的保护,针对天堂抽水蓄能电站机组变频启动过程中传统次同步过流保护时有误动的问题,提出了一种基于半波积分计算的频率无关算法。实例证明,该算法的精度不受频率变化影响,频率适应范围宽,谐波影响小。

半波积分累积式过励磁保护研究

利用一种半波积分累积式算法实现大型火电机组的过励磁保护。该方法避免了通过硬件电路采样引起的一系列不稳定因素,在现场易于调试、修改,增加了保护的可靠性,有效降低了由于更换测点采样元器件导致的停机损失。

微机保护半波积分算法误差的自适应补偿

通过对微机保护半波积分算法误差的分析，提出了一种运算量小、硬件简单的自适应式补偿误差的方法。

基于暂态波形鉴别的异步电机综合保护

针对目前异步电动机常见故障及存在问题,对电机故障特征进行了分析,提出了一种异步电机保护方案。该方案结合对称分量法,对异步电机保护的差分、傅氏算法和半波积分进行了详细分析,给出了微机保护算法模型,提出了基于暂态波形鉴别的起动与堵转保护判据,并对软件构成进行了分析,从而构成了一套完整的微机式异步电机综合保护方案。通过动模实验,说明该保护方法能够正确进行故障类型判别,验证了理论分析的正确性和可行性。

基于微机的变压器保护装置的研究

论述了变压器保护的发展历史和现状,分析了软件设计方面2种常见的算法——半波差分积分算法和半波付氏及差分算法,给出了保护软件的设计框图。介绍了硬件设计方面各种硬件插件,讨论了保护CPU插件的问题。

An Alternative Method to Study Wave Scattering by Semi-infinite Inertial Surfaces

A new method to solve the boundary value problem arising in the study of scattering of two-dimensional surface water waves by a discontinuity in the surface boundary conditions is presented in this paper. The discontinuity arises due to the floating of two semi-infinite inertial surfaces of different surface densities. Applying Green＇s second identity to the potential functions and appropriate Green＇s functions, this problem is reduced to solving two coupled Fredholm integral equations with regular kernels. The solutions to these integral equations are used to determine the reflection and the transmission coefficients. The results for the reflection coefficient are presented graphically and are compared to those obtained earlier using other research methods. It is observed from the graphs that the results computed from the present analysis match exactly with the previous results.