AC generator output controlling apparatus and method

An AC generator output controlling apparatus comprising:

• a generator driven by an internal combustion engine to generate an AC voltage;
• a rectifier for converting the generated AC voltage into a DC voltage;
• a battery charged by the converted DC voltage;
• and
• control means for determining a field current to be supplied to a field coil of said generator from said battery on the basis of a voltage deviation between a charging voltage of said battery and a target voltage of said battery, stopping supply of said field current when said voltage deviation is lower than a predetermined value, and starting the supply of said field current when said voltage deviation becomes higher than said predetermined value after the supply of said field current is stopped.

An AC generator output controlling method comprising the steps of:

• detecting the terminal voltage of a battery charged by a generator which is driven by an internal combustion engine;
• determining a target voltage on the basis of an electric load of said internal combustion engine applied to said battery and the charging state of said battery;
• determining a voltage deviation between the charging voltage of said battery and said target voltage;
• determining a control amount of the field current supplied to a field coil of said generator from said battery on the basis of said voltage deviation;
• and
• stopping the supply of said field current when said control amount is lower than a predetermined value.

An AC generator output controlling method comprising the steps of:

• detecting the terminal voltage of a battery charged by a generator which is driven by an internal combustion engine;
• determining a target voltage on the basis of an electric load of said internal combustion engine applied to said battery and the charging state of said battery;
• determining a voltage deviation between the charging voltage of said battery and said target voltage;
• determining a control amount of the field current supplied to a field coil of said generator from said battery on the basis of said voltage deviation;
• and
• stopping the supply of said field current when said voltage deviation is lower than a predetermined value, and starting the supply of said field current when said voltage deviation becomes higher than the predetermined value after the supply of said field current is stopped.

An AC generator output controlling method comprising the steps of:

• detecting the operating state of an internal combustion engine;
• detecting the terminal voltage of a battery charged by a generator which is driven by said internal combustion engine;
• determining a target voltage on the basis of the electric load of said internal combustion engine applied to said battery and the charging state of said battery;
• determining a voltage deviation .DELTA.V (i) between the terminal voltage of said battery and said target voltage;
• deciding whether or not the drive duty previously set as described below is 0%;
• if the previous drive duty is 0%, replacing the integral value (.intg.Ki.DELTA.Vdt (i)) of the present voltage deviation .DELTA.V (i) by the integral value (.intg.Ki.DELTA.Vdt (i-1)) of the previous voltage deviation .DELTA.V (i-1);
• if the previous drive duty is not 0%, computing the integral value (.intg.Ki.DELTA.Vdt (i)) of the voltage deviation .DELTA.V (i) by the following equation:
• .intg.Ki.DELTA.Vdt(i)=.intg.Ki.DELTA.Vdt(i-1)+Ki.DELTA.Vdt(i);
• computing a basic duty (Duty) for a field coil on the basis of the integral value (.intg.Ki.DELTA.Vdt (i)) of said voltage deviation .DELTA.V (i) by the following equation:
• Duty=Kp-.DELTA.V(i)+.intg.Ki.DELTA.Vdt(i)+Kd-(.DELTA.V(i)-.DELTA.V(i-1)
• (wherein Kp is a proportional gain, Ki is an integral gain and Kd is a differential gain);
• correcting the computed basic duty on the basis of the number of revolutions per minute of said engine and the terminal voltage of said battery to determine a drive duty;
• deciding whether or not said drive duty is lower than a predetermined value;
• if said drive duty is lower than said predetermined value, setting said drive duty to 0% and substantially stopping the operation of said AC generator by cutting off the field current supplied to said field coil;
• and
• if said drive duty is higher than said predetermined value, supplying the field current to said field coil from said battery with the set drive duty.

An AC generator output controlling method comprising the steps of:

• detecting the operating state of an internal combustion engine;
• detecting the terminal voltage of a battery charged by a generator which is driven by said internal combustion engine;
• determining an optimum target voltage on the basis of the electric load of said internal combustion engine applied to said battery and the charging state of said battery;
• determining a voltage deviation between the terminal voltage of said battery and said target voltage;
• comparing said voltage deviation with a first predetermined value;
• if said voltage deviation is lower than said first predetermined value, comparing the previous set drive duty with a second predetermined value;
• if said previous drive duty is lower than said second predetermined value, setting said drive duty to 0%;
• if said voltage deviation is higher than said first predetermined value, or if said drive duty is not 0%, determining the integral value (.intg.Ki.DELTA.Vdt (i)) of the present voltage deviation .DELTA.V (i) by the following equation:
• .intg.Ki.DELTA.Vdt(i)=.intg.Ki.DELTA.Vdt(i-1)+Ki.DELTA.Vdt(i);
• computing a basic duty (Duty) for a field coil on the basis of the integral value (.intg.Ki.DELTA.Vdt (i)) of said voltage deviation .DELTA.V (i) by the following equation:
• Duty=Kp-.DELTA.V(i)+.intg.Ki.DELTA.Vdt(i)+Kd-(.DELTA.V(i)-.DELTA.V(i-1))
• (wherein Kp is a proportional gain, Ki is an integral gain and Kd is a differential gain);
• correcting the computed basic duty on the basis of the number of revolutions per minute of said engine and the terminal voltage of said battery to determine a drive duty;
• and
• supplying the field current to said field coil from said battery with the set drive duty.