Benefits of CCVT secondary voltage compensation on traveling wave-based fault locators

In this paper, the influence of the frequency response of coupling capacitor voltage transformers (CCVT) on traveling wave-based fault locators is analyzed, highlighting the benefits of the CCVT secondary voltage compensation when only voltage measurements are available. In order to do so, the frequency response of a well-known 230 kV CCVT model is evaluated and a digital compensator is proposed. Several fault scenarios in a 230 kV power system were simulated via Alternative Transients Program (ATP). In each case, the fault point was estimated using a two-terminal traveling wave-based fault location algorithm, considering as inputs the primary voltages, secondary voltages and secondary voltages corrected by the proposed digital compensator. For a more thorough evaluation, the analyzed fault location method was implemented using two different transient detection algorithms available in the literature. The obtained results indicate that the CCVT frequency response compensation is effective and suitable for traveling wave-based fault locators.