| 摘要 |
PURPOSE:To alleviate the labor in periodic inspection/maintenance work of synchronous throw-in relay input circuit while keeping the accuracy of relay. CONSTITUTION:Single monitored voltage ew and system voltages e1, e2 are inputted through voltage input circuits VI1, VI2, respectively. A voltage difference operating section 1A and a phase difference operating section 2A operate output voltage difference and phase difference of the voltage input circuits VI1, VI2, respectively. Voltage difference and phase difference within an allowable range, operated through respective operating sections 1A, 2A for the monitored voltage ew, are then stored in a voltage difference memory Mv and a phase difference memory Mtheta, respectively. Subtracting means Ad1, Ad2 then subtract the voltage difference and the phase difference stored in the memories Mv, Mtheta from system voltage difference and phase difference operated through respective operating sections 1A, 2A for the system voltages e1, e2. Thus obtained outputs are employed as corrected voltage difference DELTAV' and corrected phase difference DELTAtheta' of both system voltages in the decision of circuit breaker throw-in conditions. |
