On-load automatic voltage regulation system designed via thyristor for distribution transformer

At present, voltage regulation of no load distribution transformer is not flexible and failure rate of mechanical on-load tap-changers is high. To solve these problems, a scheme of automatic on-load voltage regulation system designed via thyristor for distribution transformer was proposed. The system improved the existing topology of on-load voltage regulation system via power electronic device and added the overvoltage protection circuit of thyristor. The prototype of automatic voltage regulation system has been tested completely. The results show that, compared with the voltage regulation system via mechanical switch, transition waveforms of voltage regulation system via thyristor are of better quality and transition time is shorter.