Power Output Apparatus, Control Method of Power Output Apparatus, and Vehicle Equipped with Power Output Apparatus

A vehicle, said vehicle comprising:

• an internal combustion engine;
• an electric power-mechanical power input output mechanism that is connected with an output shaft of the internal combustion engine and with a driveshaft that is linked to an axle and inputs and outputs power from and to the output shaft and the driveshaft through input and output of electric power and mechanical power;
• a motor that is capable of inputting and outputting power from and to the driveshaft;
• an accumulator unit that transmits electric power to and from the electric power-mechanical power input output mechanism and the motor;
• an input/output limits setting module that sets input and output limits of the accumulator unit as chargeable and dischargeable maximum and minimum electric powers in and from the accumulator unit, according to a state of charge of the accumulator unit;
• a maximum/minimum control rotation speeds setting module that sets maximum and minimum control rotation speeds as upper limit and lower limit control rotation speeds of the internal combustion engine, based on the set input and output limits of the accumulator unit;
• a driving force demand specification module that specifies a driving force demand required for the driveshaft;
• and
• a control module that, when output of the specified driving force demand to the driveshaft with a variation in rotation speed of the internal combustion engine is attainable in a control restriction range defined by the set input and output limits of the accumulator unit and the set maximum and minimum control rotation speeds, controls the internal combustion engine, the electric power-mechanical power input output mechanism, and the motor to enable the specified driving force demand to be output to the driveshaft in the control restriction range,
• when the output of the specified driving force demand to the driveshaft with the variation in rotation speed of the internal combustion engine is unattainable in the control restriction range, said control module controlling the internal combustion engine, the electric power-mechanical power input output mechanism, and the motor to enable a preset driving force, which depends upon the specified driving force demand, to be output to the driveshaft in a performance-based restriction range,
• where the performance-based restriction range is defined by the set input and output limits of the accumulator unit and performance-based maximum and minimum rotation speeds as performance-dependent upper limit rotation speed and lower limit rotation speed of the internal combustion engine.

A control method of a power output apparatus, said power output apparatus having:

• an internal combustion engine;
• an electric power-mechanical power input output mechanism that is connected with an output shaft of the internal combustion engine and with the driveshaft and inputs and outputs power from and to the output shaft and the driveshaft through input and output of electric power and mechanical power;
• a motor that is capable of inputting and outputting power from and to the driveshaft;
• and an accumulator unit that transmits electric power to and from the electric power-mechanical power input output mechanism and the motor,
• said control method comprising the steps of:
• (a) setting input and output limits of the accumulator unit as chargeable and dischargeable maximum and minimum electric powers in and from the accumulator unit, according to a state of charge of the accumulator unit, and setting maximum and minimum control rotation speeds as upper limit and lower limit control rotation speeds of the internal combustion engine, based on the set input and output limits of the accumulator unit;
• and
• (b) when output of a specified driving force demand to the driveshaft with a variation in rotation speed of the internal combustion engine is attainable in a control restriction range defined by the set input and output limits of the accumulator unit and the set maximum and minimum control rotation speeds, controlling the internal combustion engine, the electric power-mechanical power input output mechanism, and the motor to enable the specified driving force demand to be output to the driveshaft in the control restriction range,
• when the output of the specified driving force demand to the driveshaft with the variation in rotation speed of the internal combustion engine is unattainable in the control restriction range, controlling the internal combustion engine, the electric power-mechanical power input output mechanism, and the motor to enable a preset driving force, which depends upon the specified driving force demand, to be output to the driveshaft in a performance-based restriction range,
• where the performance-based restriction range is defined by the set input and output limits of the accumulator unit and performance-based maximum and minimum rotation speeds as performance-dependent upper limit rotation speed and lower limit rotation speed of the internal combustion engine.