Patent ID: 8136617

Claim:
A power output apparatus that outputs power to a drive shaft, said power output apparatus comprising: an internal combustion engine; a power conversion mechanism that converts at least part of output power of the internal combustion engine into electric power; a motor that outputs power to the drive shaft; an accumulator unit that transmits electric power to and from the power conversion mechanism and the motor; an input output limit setting module that sets at least either of an input limit and an output limit of the accumulator unit, as a lower limit and an upper limit of an allowable electric power range input from and output to the accumulator unit, based on an operation or a stop of the internal combustion engine, the limit setting occurring after a determination is made as to whether the engine is operating or stopped; a power demand specification module that specifies a power demand to be output to the drive shaft; and a control module that controls the internal combustion engine, the power conversion mechanism, and the motor to output a required power corresponding to the specified power demand to the drive shaft while keeping the input from and the output to the accumulator unit within the input limit and the output limit of the accumulator unit, wherein said input output limit setting module sets at least either of the input limit and the output limit to narrow the allowable electric power range during an operation of the internal combustion engine, compared with the allowable electric power range during a stop of the internal combustion engine.