基于对称分量法的dq变换电压检测法

A voltage detection method based on dq transformation and symmetric component method

针对传统电压跌落检测算法存在不能快速识别不对称电压跌落故障类型及故障相的问题,提出了一种基于对称分量法的dq变换电压检测法。首先利用对称分量法对电压进行分解,将不对称电压分解为各自对称的正序、负序及零序分量,再对分解后的各分量进行同步旋转坐标系dq变换,得到各种故障情况下电压正序、负序和零序的幅值和相位信息,最后对变换后的结果进行重组分析。以发生频率较高的短路故障引起的电压跌落为例,对短路故障电压进行变换与重组,根据重组结果不仅可以识别故障类型,而且可以定位具体故障相。与传统dq电压变换法的仿真比较验证了该方法的准确性与优越性。

In view of problem that fault type and phase of asymmetric voltage sag could not be quickly identified by traditional voltage sag detection algorithm,a voltage detection method based on dq transformation and symmetric component method was proposed.Firstly,the voltage is decomposed by symmetrical component method,and the asymmetrical voltage is decomposed into symmetrical positive,negative and zero sequence components.Then the decomposed components are transformed into synchronous rotating coordinate system dq to obtain the amplitude and phase information of positive,negative sequence and zero sequence components of voltage components under various faults.Finally,the results of the transformation are reorganized.Taking voltage sag caused by short circuit fault with high frequency as an example,the short circuit fault voltage is transformed and reorganized.According to the recombination results,not only the fault type can be identified,but also the specific fault phase can be located.The simulation comparison with the traditional dq voltage transformation method verifies accuracy and superiority of the method.