Power conversion with stop conversion during low integrated power conditions

摘要

In a solar power generation apparatus, when power necessary for a control circuit and the like is supplied from the load side of an inverter, a period from when the input voltage becomes lower than a threshold voltage at which the inverter should be stopped to when the inverter is stopped after the elapse of a predetermined time includes a period when power consumed by the inverter become larger than power output from the inverter, i.e., power is wasted. To solve this problem, input power is integrated for a predetermined time to calculate integrated electric energy. The calculated integrated electric energy W1 is compared with a threshold value Y1. If W1Y1, a gate block signal is output to stop the operation of the inverter. As the threshold value Y1, a value corresponding to the product of the non-load power of the inverter and the predetermined time T1 is set.