Software evaluation of step response parameters of high voltage dividers

High voltages are measured using a measuring system consisting of a high voltage divider, transmission system and recording instruments. These measuring equipment must to be calibrated periodically to have an accuracy within permissible limits. It involves determination of scale factor, linearity and its validity range with respect to signal parameters like frequency, amplitude and time parameters especially for impulse measuring systems. The time parameters can be determined by comparing the measuring system under test with another calibrated reference divider or by using a unit step generator. In this paper, different methods available to calibrate the high voltage measuring system such as methodology for voltage comparison method and dynamic response method are discussed. A software is also developed at CPRI to evaluate the divider time parameters such as base magnitude, settling level, virtual origin, overshoot β, distortion time T_o, partial response time T_α, experimental response time T _N, residual response time T_R, and settling time t ₅. In order to check the validity of the software developed, international sample data for different step responses are considered. The response parameters of these data are compared with the response parameters evaluated by the software developed at CPRI. The paper describes the details of the algorithm and capabilities of the software