基于延迟小角度法和自适应复合形态滤波器的 电压暂降检测方法

针对当前现代电网建设电压暂降故障频发和传统电压暂降检测算法准确性和快速性不足的问题,提出一种电压暂降检测新方法。单相电压首先经过自适应复合形态滤波器进行最优尺度滤波处理,再延迟一个小角度构造相互垂直且正交的αβ两相电压,经过αβ-dq变换得到电压暂降幅值、相位跳变和持续时间等特征量。在Matlab/Simulink中搭建新型电压暂降检测算法仿真模型,与传统滤波算法和电压暂降检测算法进行了对比分析。基于TMS320F28069DSP处理器设计了高速的数据采集与处理电路,搭建了电压暂降检测平台,对所提方法进行了工程验证。仿真结果表明所提方法在电网谐波噪声干扰、电压暂降、相位跳变等工况下具有较高的准确性及灵敏度,实测系统总体响应时间小于5 ms,所提方法可行有效。

Voltage sag detection method based on the delayed small angle method and an adaptive composite morphological filter

In order to solve the problems of frequent voltage sag faults in modern power grid construction as well as insufficient accuracy and speed of traditional voltage sag detection algorithms,a new voltage sag detection method is proposed.First,the single-phase voltage is filtered by an adaptive composite morphological filter at optimal scale.Then,the single-phase voltage is delayed by a small angle to construct mutually perpendicular and orthogonalαβtwo-phase voltages.Afterαβ-dq transformation,characteristic quantities such as voltage transient amplitude,phase jump and duration are obtained.The new voltage sag detection algorithm simulation model is built in Matlab/Simulink.It is compared with traditional filtering algorithms and voltage sag detection algorithms.Based on a TMS320F28069DSP processor,a high-speed data acquisition and processing circuit is designed,and a voltage sag detection platform is built,The proposed method has passed engineering verification.The simulation results show that the proposed method has high accuracy and sensitivity under harmonic noise interference,voltage sag,phase jump and so on,and the overall response time of the measured system is less than 5 ms.The proposed method is feasible and effective.