Engine startup control device and control method

An engine startup control device for use with an engine started by a motor, comprising:

• a sensor which detects a rotation speed of the engine;
• a power controller which varies a current supplied to the motor according to a signal;
• and
• a microprocessor programmed to:
• determine whether or not the rotation speed of the engine has reached a predetermined target rotation speed;
• and
• set the signal so that the rotation speed of the engine is maintained at the target rotation speed after the rotation speed of the engine has reached the target rotation speed.

An engine startup control device for use with a hybrid vehicle, the vehicle comprising an engine, a first motor for starting the engine, a generator for driving the engine, a drive wheel connected to the engine via a clutch, a second motor for driving the drive wheel and a battery which can be connected to the first motor, the second motor and the generator, the control device comprising:

• means for detecting a rotation speed of the engine;
• means for detecting a charge amount of the battery;
• a power control means for varying a current supplied to the first motor according to a signal;
• means for calculating a target output torque of the first motor according to the charge amount of the battery;
• means for setting the signal so that an output torque of the first motor coincides with a predetermined target output torque when the rotation speed of the engine is less than a predetermined target rotation speed;
• and
• means for setting the signal so that the rotation speed of the engine is maintained at the target rotation speed after the rotation speed has reached the target rotation speed.

An engine startup control method for a hybrid vehicle, the vehicle comprising an engine, a first motor for starting the engine, a generator for driving the engine, a drive wheel connected to the engine via a clutch, a second motor for driving the drive wheel, a battery which can be connected to the first motor, the second motor and the generator, and a power controller which varies a current supplied to the first motor according to a signal, the control method comprising:

• detecting a rotation speed of the engine;
• detecting a charge amount of the battery;
• calculating a target output torque of the first motor according to the charge amount of the battery;
• setting the signal so that an output torque of the first motor coincides with a predetermined target output torque when the rotation speed of the engine is less than a predetermined target rotation speed;
• and
• setting the signal so that the rotation speed of the engine is maintained at the target rotation speed after the rotation speed of the engine has reached the target rotation speed.