DETERMING AND ANALYSING PERFORMANCE CHARACTERISTICS OF HIGH-VOLTAGE ELECTROTECHNICAL SYSTEMS BASED ON A SERIES RESONANT LC-CIRCUIT WITH A HIGH Q-FACTOR

Abstract

The paper analyzes the performance characteristics of the electrоtechnical system (ETS), built on the basis of a series high-Q resonant LC circuit and intended for diagnosing the isolation of high-voltage equipment. The frequency dependences of the parameters L and C elements of the resonant circuit were experimentally studied and it was shown that for both elements there is an optimal frequency at which the value of the element’s Q- factor reaches its maximum value. It was established that the Q-factor of the investigated circuit is determined mainly by the Q-factor of its inductance and reaches the maximum value QLC,max = 280 at the frequency f= 40 kHz. The Simulink model was developed for the analysis of the performance characteristics of the ETS in steady state. Graphical dependences are given, which allow to determine the level of voltage on the load for a given active resistance of this load, as well as the energy characteristics and the value of the efficiency of the ETS at the stage of its design. A Simulink model has also been developed to analyze the dynamic characteristics of the ETS when a breakdown of the diagnosed insulation occurs. It is shown that the breakdown of the insulation in the ETS, which has a series high-Q resonant circuit, will cause a rapid decrease in current by Q times, and not an increase in current to emergency values, as in an ETS based on high-voltage transformers. In this way, a fast-acting parametric stabilization of the output current is implemented in the ETS even in case of electrical breakdowns of the high-voltage insulation of the power equipment under diagnosis. Thus, the ETS implements high-speed parametric stabilization of the output current, which prevents the destruction of both the ETS and the diagnosed high-voltage insulation of power equipment even during its electrical breakdown. References 11, figures 9.