| 摘要 |
PROBLEM TO BE SOLVED: To prevent unwanted current (cross current) from flowing among generators without finding a power factor of a load when a plurality of the engine generators are paralelly operated. SOLUTION: In a cross current controlling process which is conducted in a parallel operation equipment, the output voltage and the current of a generator are detected in a step (hereinafter abbreviated as S) 110 and a phase difference between the output voltage and the current is detected in S120. In S130, a reactive current Ir is calculated from the phase difference and the current detected in S110. In S140, the reactive current Ir and a target value I0 are compared. When the reactive current Ir is larger, the next step is S150 and there the voltage is stepped down. When the reactive current is smaller, the next step is S160 and there the voltage is stepped up. If all the generators get through this process, the voltage is converged to a value corresponding to the reactive current I0 and there is no appearing of cross current. Furthermore, there is no necessity of finding a power factor of a load and so no structure nor wiring for detecting the power factor is required. |
