Voltage controller for HV DC converter station - uses ideal no load voltage as reference for transformer tap changer regulation

摘要

By using the ideal rectifier or inverter no load direct voltage as the reference the frequency of operation of the onload tap changer of the converter transformer can be reduced and its useful life thus prolonged. Also a more uniform operation of the converter results. This reference is compared with an ideal no load direct voltage obtained from the actual ac line voltage to form an error sinal. The reference can also be corrected for the d.c. inductive volt drop due to load to give a more accurate value.