摘要 |
PROBLEM TO BE SOLVED: To provide a single operation detection circuit which neither is influenced by nor influences a single operation detection function of another distributed power source even in the case where a plurality of distributed power sources are interconnected to the same distribution system.SOLUTION: A single operation detection circuit 6 comprises: a model based calculation section 61 in which a formula based on a mathematical model in the state where a system interconnection inverter system A is being interconnected to a power system C, is being set and which calculates an α-axis current signal iα in accordance with a compensation signal xα inputted from a stationary coordinate transformation section 31e and the preset formula; and a single operation determination section 62 which compares the α-axis current signal iα calculated by the model based calculation section 61 with an α-axis current signal iα inputted from a three-phase/two-phase conversion section 31a and, in the case where it is determined that both the signals are different, determines a single operation state. |