Leydig, Voit & Mayer, Ltd.
Controller for performing a decoupling control of a transformerless reactive series compensator
 A controller for generating a modulation signal m applied to a transformerless reactive series compensator connected serially in a power transmission line. A modulation signal generator generates a modulation signal m in the form of m=m.sub.d cos (.omega.t)-m.sub.q sin (wt). The controller includes a current control loop with a current controller outputting the modulation index m.sub.q of the modulation signal m. A voltage control loop including a DC voltage controller outputs the modulation index m.sub.d, of the modulation signal m. The current control loop and the voltage control loop are respectively provided for outputting indices m.sub.q ', m.sub.d ' in order to control a line current and a DC capacitor voltage of a capacitor of the compensator to reference values. The controller includes a decoupler so that the line controller and the capacitor voltage are independent of the output of the current controller. Therefore, the amplitude of the line current and the magnitude of the DC capacitor voltage can be controlled completely independently from each other, i.e., the control loops are decoupled. 
Mitsubishi Denki Kabushiki Kaisha
Y H
Y02E H02J
additional inventional
Toshiyuki Andreas
Fujii Beer