Patent ID: 9537312
Date: 2017-01-03
CPC Classifications: H02J,Y02E

Claim:
1. A cogeneration apparatus having a power generation unit equipped with a power generator adapted to be connected to an AC power feed line at a location between a commercial power source and an electric load and an internal combustion engine for driving the generator, comprising: a switch installed at a location between the power generation unit and an outage power output to be connected to the electric load at outage of the commercial power source; the power generation unit being adapted to be connected to the AC power feed line through the switch; the switch disconnecting the power generation unit from the AC power feed line and connecting the power generation unit to the outage power output, disconnecting the power generation unit from the outage power output and connecting the power generation unit to the AC power feed line, or disconnecting the power generation unit from the AC power feed line and the outage power output; a total engine operation time period calculator that calculates a total operation time period of the engine; an outage occurrence determiner that determines whether the outage of the commercial power source occurs; a power generation capability determiner that estimates a degree of deterioration of the power generation unit based on one of the calculated total operation time period of the engine, a calculated cooling water temperature difference between a temperature of cooling water heated by the engine to be supplied to a heat exchanger and a temperature of the cooling water cooled by the heat exchanger to be returned to the engine, a calculated in-case temperature difference between a temperature at a location above the power generator and a temperature at a location below the power generator in direction of gravity in a case housing the power generator, and a detected voltage of generated power at a position before the switch, and determines whether the power generation unit is capable of generating power based on the estimated degree of deterioration of the power generation unit when the outage is determined to occur; and a power generation controller that controls the switch to disconnect the power generation unit from the outage power output and to connect the power generation unit to the AC power feed line to supply combined power of the power generation unit and the commercial power source combined through the AC power feed line to the electric load through the AC power feed line, if the calculated total operation time period of the engine is equal to or smaller than a predetermined first time period when the outage is determined not to occur, and controls the switch to disconnect the power generation unit from the AC power feed line and to connect the power generation unit to the outage power output to supply the power generated by the power generation unit to the electric load through the outage power output, if the power generation unit is determined to be capable of generation power when the outage is determined to occur.