Patent ID: 11942790
Assignee: GENERAL ELECTRIC TECHNOLOGY GMBH
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 13:
14. A method of controlling a frequency set-point (FRef) for a first AC network connected to a first HVDC station to regulate active power, the method comprising:
monitoring a measured value of DC voltage at the first HVDC station (VDC1) for a predetermined characteristic indicative that a variation in measured DC voltage corresponds to a known modulation applied to the DC voltage by a second HVDC station;
if the predetermined characteristic is detected, determining the frequency set-point based on the measured value of DC voltage (VDC1) at the first HVDC station; and
if the predetermined characteristic is not detected control the frequency set-point (FRef) for the first AC network to a predetermined default frequency; and
comparing a first value based on the present measured value of DC voltage (VDC1) to a second value (VDC_EST) based on the value of the frequency set-point (FRef) for the first AC network and said predetermined characteristic is that the first and second values differ by less than a defined amount (DIFF).