| 摘要 |
PURPOSE:To make the title relay device to not to be operated by a transverse flow at the time of system interconnection and surely operate when reverse power of a value higher than the transverse flow is generated by calculating the transverse flow from the voltage difference between both systems and the impedance at the time of system interconnection and raising the operational level of a reverse power detecting relay by the amount corresponding to the value of the transverse flow until a prescribed period of time has elapsed from the system interconnection. CONSTITUTION:The voltage difference calculating means 281 of an arithmetic sequence unit 28 calculates the voltage difference V between both systems. A system impedance calculating means 282 calculates the impedances of the systems on the basis of opened/closed state signals from auxiliary contacts 7a, 8a, and 9a, A transverse flow calculating means 284 calculates a transverse flow generated when both systems are interconnected. An operational level calculating means 285 calculates the operational levels of reverse power detecting relays 21, 22, and 23 so as to raise their operational levels by amounts corresponding to the value of the transverse flow. An operational level setting and outputting means 286 outputs operational level setting signals 29, 30, and to the relays 21, 22, and 23. After a prescribed period of time has elapsed, the operational levels of the relays 21, 22, and 23 are returned to their steady-state values. |
