Generator control system for a hybrid vehicle driven by an electric motor and an internal combustion engine

A hybrid vehicle comprising:

• an internal combustion engine;
• a generator connected to and driven by said internal combustion engine;
• an inverter electrically connected to said generator;
• a battery chargeable by said generator through said inverter;
• an electric motor driven by electric power supplied from said generator and said battery through said inverter, said electric motor acting as a driving source for driving vehicle wheels;
• state-of-charge detecting means for detecting a state of charge of said battery at predetermined sampling intervals to obtain a present state-of-charge (SOC) of said battery and a variation (.DELTA.SOC) of the state-of-charge of said battery during a predetermined time interval based on said present state-of-charge (SOC);
• and
• control means for controlling an electrical output of said generator based on said present state-of-charge (SOC) and said variation (.DELTA.SOC).

A control system for hybrid vehicles comprising:

• an electric motor, having both motor and generator functions to form one driving source for driving wheels of a hybrid vehicle and serve as a generating source for generating electric power;
• an internal combustion engine forming another driving source for driving said wheels of said hybrid vehicle;
• a clutch interposed between said electric motor and said internal combustion engine for selectively engaging and disengaging said internal combustion engine with and from said electric motor;
• a battery chargeable by said electric motor;
• state-of-charge detecting means for detecting a state of charge of said battery at predetermined sampling intervals to obtain a present state-of-charge (SOC) of said battery and a variation (.DELTA.SOC) of the state-of-charge of said batter v during a predetermined time interval based on said present state-of-charge (SOC);
• engine output control means for controlling an output of said internal combustion engine and a residual capacity of said battery based on said present state-of-charge (SOC) and said variation (.DELTA.SOC);
• motor function switching means for switching said electric motor between said motor function and said generator function on the basis of said control by said engine output control means;
• and
• clutch controlling means for engaging and disengaging said internal combustion engine with and from said electric motor on the basis of said control by said engine output control means.

A hybrid vehicle comprising:

• an electric motor, having both motor and generator functions to form one driving source for driving vehicle wheels of said hybrid vehicle and serve as a generating source for generating electric power;
• an internal combustion engine forming another driving source for driving said wheels of said hybrid vehicle;
• a clutch interposed between said electric motor and said internal combustion engine for selectively engaging and disengaging said internal combustion engine with and from an input shaft of said electric motor;
• an inverter electrically connected to said electric motor;
• a battery chargeable by said electric motor through said inverter;
• wherein said vehicle wheels are connected to an output shaft of said electric motor through a driving mechanism;
• state-of-charge detecting means for detecting a state of charge of said battery at predetermined sampling intervals to obtain a present state-of-charge (SOC) of said battery and a variation (.DELTA.SOC) of the state of charge of said battery during a predetermined time interval based on said present state-of-charge (SOC);
• engine output control means for controlling an output of said internal combustion engine and a residual capacity of said battery based on said present state-of-charge (SOC) and said variation (.DELTA.SOC);
• motor function switching means for switching said electric motor between said motor function and said generator function on the basis of said control by said engine output control means;
• and
• clutch controlling means for engaging and disengaging said internal combustion engine with and from said electric motor on the basis of said control by said engine output control means.

A control method for a generator used in a hybrid vehicle, comprising steps of:

• driving a generator by an internal combustion engine;
• charging a battery by electric power produced by said generator;
• driving an electric motor by electric power supplied from said generator and said battery, said electric motor having an output connected to vehicle wheels of said hybrid vehicle;
• detecting a state of charge of said battery at predetermined sampling intervals to obtain a present state-of-charge (SOC) of said battery and a variation (.DELTA.SOC) of the state of charge of said battery during a predetermined time interval based on said present state-of-charge (SOC);
• and
• controlling an electrical output of said generator based on said present state-of-charge (SOC) and said variation (.DELTA.SOC).

A control method for a hybrid vehicle comprising steps of:

• driving an internal combustion engine in accordance with vehicle driving conditions;
• selectively engaging and disengaging said internal combustion engine through a clutch to and from an input shaft of an electric motor having both motor and generator functions;
• charging a battery by electric power produced by said electric motor when said electric motor performs said generator function and discharging electric energy stored in said battery to said electric motor when said electric motor performs said motor functions;
• driving vehicle wheels connected to an output shaft of said electric motor by an output of said electric motor;
• detecting a state of charge of said battery at predetermined sampling intervals to obtain a present state-of-charge (SOC) of said battery and a variation (.DELTA.SOC) of the state of charge of said battery during a predetermined time interval based on said present state-of-charge (SOC);
• and
• controlling an output of said internal combustion engine, said electric motor and said clutch in such a manner so that a residual capacity of said battery is maintained at a predetermined level based on said present state-of-charge (SOC) and said variation (.DELTA.SOC).