Patent ID: 6710580
Filing Date: 2004-03-23
Classification: H02H,H02M,H02P

Abstract:
A method of overload-controlling an inverter power generation apparatus comprising an AC generator driven by an internal combustion engine, a rectifier to rectify an output of said AC generator and an inverter to convert an output voltage of said rectifier into an AC voltage of constant frequency, said method comprising steps of determining a first overload judgment value for a load current flowing through said inverter and a second overload judgment value larger than said first overload judgment value, determining a short circuit judgment value for an output voltage of said inverter, further determining a first setting time and a second setting time having a length set in accordance with said output voltage of said inverter, starting a measurement of an overload continuation time when it is detected that said load current exceeding said first overload judgment value flows through said inverter and judging whether the value of said load current exceeds said second overload judgment value and whether said output voltage of said inverter is equal to or less than said short circuit judgment value whereby the operation of said inverter is stopped immediately when said load current exceeds said second overload judgment value and said output voltage of said inverter is equal to or less than said short circuit judgment value, the operation of said inverter is stopped when said overload continuation time exceeds said first setting time in case that said load current is equal to or more than said first overload judgment value and is equal to or less than said second overload judgment value and the operation of said inverter is stopped when said overload continuation time exceeds said second setting time in case that said overload current exceeds said second overload judgment value and said output voltage of said inverter exceeds said short circuit judgment value wherein said second setting time is so set as to get shorter as said output voltage of said inverter is lower.