On-line Monitoring of Measurement Errors of CVT Based on Independent Component Analysis

Capacitive voltage transformers have been widely used in high-voltage power grids of 110 kV and above. Generally, the regular off-line detection method of the standard transformer is adopted, and there are problems such as difficulty in power failure and difficult operation. A method for on-line monitoring of measurement errors of CVT is proposed. The CVT secondary output amplitude data is correlated under normal operation. The correlation analysis is performed on the data based on ICA, and a new comparison standard quantity is established without the standard transformer. The information of measurement errors is quantified, and the on-line monitoring of measurement errors of CVT is realized by comparing the quantified value of measurement errors. Simulation experiments show that the method meets the accuracy requirements of class 0.2, and the evaluable amplitude change is better than 0.05%.