METHOD AND DEVICE FOR REGULATING SYSTEMATIC REACTIVE POWER IN HIGH VOLTAGE DC TRANSMISSION

摘要

The difference between the required and actual value of the direct current Jd is supplied as a current regulating parameter to a current regulator (PJ1) which influences the transformation ratio (üT) of the station transformer such that its output parameter is held within specific limits and, on reaching one of the two limit values (üTmax, üTmin) of the transformation ratio of the converter transformers, means of compensation (C1, C2) are brought into readiness which, on reaching specific limits of the control angle ( alpha , gamma ), which is dependent on the output parameter of the current regulator (PJ1) and of the network reactive power (Q), are connected, subject to direct previous control, to the respective opposite control angle limit values ( alpha min, gamma min; alpha max, gamma max). The current regulation parameter is interrogated at regular intervals for direct current changes and these direct current changes are fed to a current function transmitter (FGJ) in the event of increasing direct current changes increasing network reactive power. The output parameter thereof is multiplied by the respective control angle ( alpha ) or ( gamma ) and the product is added to the power regulation parameter from the difference between the required and actual value of the network reactive power (Q) and the sum of both parameters is fed to an angle function transmitter (FG alpha ( gamma )) in the case of a decrease in control angle ( alpha ; gamma ) resulting in an increased network reactive power. The output parameter thereof (control angle change DELTA alpha , DELTA gamma ) is multiplied by the actual value of the direct current (Jdx) and the product is added to the said current regulation parameter for the purpose of forming the control angle ( alpha , gamma ) for the rectifier or converter stations (GR, WR), a correspondingly negative correction parameter being supplied on reaching the maximum value of the relevant control angle ( alpha max; gamma max) and a corresponding positive correction parameter being supplied on reaching the minimum value of the relevant control angle ( alpha min; gamma min), which parameters switch the said means of compensation (C1, C2) on or off. IMAGE