| 摘要 |
PURPOSE:To maintain a voltage and a reactive power at prescribed values by detecting that the ratio between a change rate with time of a load of a power system and a change rate with time of the reactive power is a prescribed value or above and by conducting a switching control of phase modifying equipment in the direction of making the voltage of the power system rise. CONSTITUTION:Based on an apparent power W, a load increase determining element 13 always detects a change rate Q/ t of a reactive power Q and a change rate W/ t of the apparent power W within a unit time t being shorter than an integrated time in a voltage-reactive power control element 12. When the ratio with the change rate Q/ t of the reactive power becomes a prescribed value alpha or above, lowering of a system voltage V is estimated, and prior to a control according to an integration characteristic by the voltage- reactive power control element 12, a control in the direction of making the system voltage V rise is conducted. In short, a transformer tap raising control, a reactor opening control and a capacitor making control are conducted. |
