| 摘要 |
PROBLEM TO BE SOLVED: To detect power interruption on the system side by providing a function generator for enlarging ripple in the terminal voltage of a nonutility generator, means for oscillating the set voltage of an automatic voltage regulator, and means for detection the power flow between the generator and the system. SOLUTION: The voltage command for an automatic voltage regulator 12 in a non-utility generating facility 1 is added with a function generator 17 employing that output. A power flow detection means 31, a power flow decision element 32 and a voltage command oscillation signal generator 33 for oscillating the terminal voltage of generator are added. When power is scarcely demanded by a system or when the output of non-utility generator is not balanced with a load, the detection voltage scarcely fluctuates. When the system is paralleled off, terminal voltage of the generator governed by the system voltage oscillates and the function generator 17 enlarges the voltage thus shifting the operating point of various protective relays. Consequently, a power receiving point circuit breaker is opened without requiring any expensive transfer circuit breaker. |
