| 摘要 |
PURPOSE:To stabilize a power system while preventing overload of a transformer by providing a limiter for limiting the output current from a reactive power compensator below a current level for causing overload of the transformer. CONSTITUTION:A voltage detecting circuit 7 and a current detecting circuit 10 detect the system voltage V and the output current are Isvc from a reactive power compensator (SVC) respectively, then an operating unit 9-2 takes the difference between the difference V of a set voltage Vref and the system voltage V and the output current Isvc multiplied by a constant K, thereafter a command for bringing the difference to zero is fed through a proportional integrator 12 to a firing angle determining circuit 13 thus controlling the SVC. If the detected current exceeds over the allowable load of transformer, an output for cancelling the excessive portion is provided from a negative value pass circuit 17 or a positive value pass circuit 18 and added to the output from the proportional integrator 12 through primary delays 19-1, 19-2. |
