Měření na vysokonapěťových metaloxidových svodičích přepětí

Abstract

This bachelor thesis can be split into the four main parts. In the first part of the bachelor thesis I analyze the overvoltage. We will get to know what overvoltage is, how it forms, ways of limitation and influence of it on isolation or electrical grid parameters. In the second part of the bachelor thesis we will learn about all types of surge arresters. There is description of surge arresters with ZnO resistors, types of surge arresters and tests of it. The third part of the bachelor thesis is basically practical. Our school received one of the newest surge arresters from the company called ABB without spark gaps, consisting of metaloxid resistors and covered with silicone shield. We performed two tests on this surge arresters with different nominal voltages. Measurement of residual voltage was done by impulse generator which was also provided by our school. In the fourth part measurement of the continuous current is done. This test shows dependecy of continuous current on applied voltage.