Analysis and EMTP simulation of a conventional gate firing unit for HVDC converters operating with weak AC systems

Results are presented from an EMTP study on the operational behavior of the gate firing unit (GFU) of an HVDC converter system operating with a weak AC power system. A voltage controlled oscillator (VCO) is used in conjunction with a phase locked loop (PLL) in the GFU of the HVDC converter system to achieve a satisfactory transient performance.<<ETX>>