MIXED TYPE DC/AC CONVERSION SYSTEM AND CONTROL METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a mixed type DC/AC conversion system capable of improving the conversion efficiency of DC/AC conversion.SOLUTION: The mixed type DC/AC conversion system has: a first DC power supply 10 for supplying a first DC input voltage V; a second DC power supply 20 for supplying a second DC input voltage Vwhose voltage value is larger than that of the first DC input voltage V; a power converter 30 for connecting with the first DC power supply 10 and the second DC power supply 20 in parallel and converting the first DC input voltage Vor the second DC input voltage Vinto an AC output voltage V; and a comparison unit 60. The mixed type DC/AC conversion system outputs a control signal Scontrolling the power converter 30 so as to convert the first DC input voltage Vinto the AC output voltage Vwhen an absolute value of the AC output voltage Vis an external reference voltage Vor lower, and outputs the control signal Scontrolling the power converter 30 so as to convert the second DC input voltage Vinto the AC output voltage Vwhen the absolute value of the AC output voltage Vis the external reference voltage Vor larger.