| 摘要 |
PROBLEM TO BE SOLVED: To detect and protect an isolated operation of private power generation facility securely and easily in case of an outage on the system side under the condition that a reverse power flow can happen, on the private power generation facility side, without providing an expensive transfer interruption device. SOLUTION: A system interconnection protection device comprises a speed governor 14a which control a frequency of a generator 11a in private power generation facility interconnected with AC electric power system under the condition that the reverse power flow can happen, a function generating means 30a, 31a, 32a having a function property of a frequency command such as to detect a change rate of the frequency of the generator 11a and to output a big output signal as against thereto, an effective power adjustment means 36a which outputs an output signal corresponding to an effective power of the generator 11a, and a protective relay means 33a, 34a which sense anomaly of the frequency change rate of the generator 11a, wherein a signal which is a resultant of the output signals of the function generating means 30a, 31a, 32a and the output signal of the effective power adjustment means 36a is defined as a command signal of the speed governor 14a and the frequency change rate of the generator 11a is shifted to the level for which the protective relay 33a, 34a can perceive by means of the function property of the function generating means, thereby power outage of the AC electric power systems is detected. |
