A novel protection equipment of test transformer

EPEROV test transformer overvoltage protection equipment has been designed by the authors. This kind of protection equipment has proved to be one of the best candidates for the protection of test transformers. Compared with conventional methods, EPEROV is a newly developed technical measure of protecting test transformers. It consists of a pair of SCRs (silicon-controlled rectifiers) connected in negative parallel on the primary of the test transformer, C1 and C2 (voltage divider capacitors), a voltage comparator, logic output time circuit, input stage, amplifier stage and wide broad pulse row. The basic principle of EPEROV is that when a flashover occurs on the secondary of a test transformer, the pair of SCRs connected in negative parallel will short circuit the primary of the test transformer instantly, so as to cost the energy of the secondary. Therefore, the overvoltage will be inhibited effectively. At the time of the writing of this paper, EPEROV has completed two years of successful and reliable operation.