Charging control apparatus for vehicle generators

• US 5,243,270 A
• Filed: 11/28/1990
• Issued: 09/07/1993
• Est. Priority Date: 11/29/1989
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Inventors: Tsuzuki, Tomoni, Mayumi, Nobuo, Tanaka, Kouzi
• Primary Examiner(s): Stephan, Steven L.
• Assistant Examiner(s): Dougherty, Thomas M.
• Application Number:
  US07/618,309
• Time in Patent Office: 1,014 Days
• Field of Search: 320/64, 322/99
• US Class Current: 322/28
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/2434 with pulse modulation
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles

Abstract

A battery charging control apparatus for a vehicle generator comprises switching means for controlling a field current flowing through a field winding of the generator intermittently, voltage control means for controlling the switching means to increase the field current gradually in order to maintain a voltage of a battery to be charged at a first predetermined value when the battery voltage drops below the first predetermined value, generator output voltage detecting means for detecting an output voltage of the generator, charging abnormality warning means, which detects occurrence of charging abnormality, when the detected generator output voltage drops to assume a second predetermined value and below, which value is lower than the first predetermined value, and at the same time the battery voltage remains at the first predetermined value and below for a predetermined time, and which then turns on a charging abnormality warning lamp, and current increasing means which increases the field current to thereby increase the generator output voltage to assume the second predetermined value and above within the predetermined time, when the charging abnormality has occurred, whereby it is made possible to prevent erroneous lighting of the charging abnormality warning lamp.

Claims

1. A charging control apparatus for a vehicle generator having a stator winding and a field winding and driven by an engine to generate an output voltage for charging a battery, said apparatus comprising:

switching means, connected to said field winding, for controlling a current flowing through said field winding;

means for monitoring a voltage of said battery;

voltage control means, responsive to said monitoring means, and connected to said switching means for receiving a first reference voltage and comparing said battery voltage with said first reference voltage, and for producing a controlling output for controlling said switching means to gradually increase the current flowing through said field winding at a first rate when the battery voltage drops to be lower than the first predetermined voltage;

generator output voltage detecting means, connected to an output of said generator, for detecting an output voltage of said generator;

charging abnormality warning means, connected to said generator output voltage detecting means, for detecting a charging abnormality and producing an indication to inform an operator of the charging abnormality, including means for receiving a second predetermined voltage lower than said first reference voltage and comparing the generator output voltage detected by said generator output voltage detecting means therewith, and means coupled to said comparing means of said voltage control means for receiving a first signal indicating that the battery voltage is at the first reference voltage or below and for delaying said first signal for a predetermined time to produce a delayed first signal, said indication produced when said generator output voltage is at or lower than said second predetermined voltage, and said delayed first signal is produced; and

current increasing means coupled between said voltage control means and said switching means and receiving said controlling output of said voltage control means, for driving said switching means at an amount in accordance with said controlling output of said voltage control means, and for increasing an amount of driving of said switching means to increase the current flowing through said field winding to an increased rate higher than said first rate to thereby increase the generator output voltage to exceed the second predetermined voltage within said predetermined time, when the generator output voltage drops to the second predetermined voltage or lower and the battery voltage drops to the first reference voltage or lower.

7. An apparatus as in claim 1 wherein said gradual control by said voltage control means is by adjustment of its duty cycle.

2. A charging control apparatus for a vehicle generator which has a stator winding and a field winding and which is driven by an engine to generate an output voltage for charging a battery, said apparatus comprising:

switching means, connected to said field winding, for controlling a current flowing through said first winding;

means for monitoring a voltage of said battery;

voltage control means, responsive to said monitoring means, and connected to said switching means, for receiving a first reference voltage and comparing said battery voltage with said first reference voltage, and for outputting a control signal which controls an ON/OFF state of said switching means at a first rate to maintain the battery voltage at a predetermined value;

excitation control means, for producing a drive signal for said switching means that will increase the current flowing through said field winding to an increased rate higher than said first rate of increase;

generator output voltage detecting means connected to an output of said generator, for detecting an output voltage of said generator;

charging abnormality warning means, connected to said generator output voltage detecting means, for detecting a charging abnormality and producing an indication to inform an operator of the charging abnormality, including means for receiving a second predetermined voltage lower than said first reference voltage and comparing the generator output voltage detected by said generator output voltage detecting means therewith, and means coupled to said comparing means of said voltage control means for receiving a first signal indicating that the battery voltage is at the first predetermined voltage or below and for delaying said first signal for a predetermined time to produce a delayed first signal, said indication produced when said generator output voltage is at or lower than said second predetermined voltage, and said delayed first signal is produced; and

change-over means receiving said control signal from said voltage control means and receiving said drive signal from said excitation control means, for driving said switching means at an amount in accordance with said output of said voltage control means, and for increasing an amount of driving of said switching means to increase the current flowing through said field winding to said increased rate higher than said first rate to thereby increase the generator output voltage to exceed the second predetermined value within the predetermined time by controlling said switching means using the control signal of said voltage control means in place of the control signal of said excitation control means, when the generator output voltage drops to the second predetermined voltage and below and the battery voltage drops to the first reference voltage and below.

3. A charging control apparatus for a vehicle generator which has a stator winding and a field winding and which is driven by an engine to generate an output voltage for charging a battery, said apparatus comprising:

switching means, connected to said field winding, for controlling a current flowing through said field winding;

means for monitoring a voltage of said battery;

voltage control means, responsive to said monitoring means, and connected to said switching means, for receiving a first reference voltage and comparing said battery voltage with said first reference voltage, and for outputting a control signal which controls an ON/OFF state of said switching means at a first rate to maintain the battery voltage at a predetermined value;

excitation control means for producing a drive signal for said switching means that will increase the current flowing through said field winding to an increased rate higher than first rate of increase;

generator output voltage detecting means connected to an output of said generator, for detecting an output voltage of said generator;

charging abnormality warning means, connected to said generator output voltage detecting means, for detecting a charging abnormality and producing an indication to inform an operator of the charging abnormality, including means for receiving a second predetermined voltage lower than said first reference voltage and comparing the generator output voltage detected by said generator output voltage detecting means therewith, and means coupled to said comparing means of said voltage control means for receiving a first signal indicating the battery voltage is at the first reference voltage or below and delaying said first signal for a predetermined time to produce a delayed first signal, said indication produced when said generator output voltage is at or lower than said second predetermined voltage, and said delayed first signal is produced; and

change-over means receiving said control signal from said voltage control means and receiving said drive signal from said excitation control means, for driving said switching means at an amount in accordance with said output of said voltage control means, and for increasing an amount of driving of said switching means to increase the current flowing through said field winding to said increased rate higher than said first rate to thereby increase the generator output voltage to exceed the second predetermined value within the predetermined time by controlling said switching means using the control signal of said voltage control means in place of the control signal of said excitation control means, when the generator output voltage drops to the second predetermined value and below and the battery voltage drops to the first predetermined value and below, where said cross-over means includes means for receiving third voltage higher than said second predetermined voltage and means for comparing the output voltage of said generator with said third voltage, said change-over means controls said switching means using the control signal of said excitation control means after the output voltage of said generator has reached said third voltage.

4. A charging control apparatus for a vehicle generator which has a stator winding and a field winding and which is driven by an engine to generate an output voltage for charging a battery, said apparatus comprising:

switching means, connected to said field winding, for controlling a current flowing through said first winding;

means for monitoring a voltage of said battery;

voltage control means, responsive to said monitoring means, and connected to said switching means for receiving a first reference voltage and comparing said battery voltage with said first reference voltage, and for outputting a control signal which controls an ON/OFF state of said switching means at a first rate to maintain the battery voltage at a predetermined value;

excitation control means for producing a drive signal for said switching means that will increase the current flowing through said field winding to an increased rate higher than said first rate;

generator output voltage detecting means connected to an output of said generator, for detecting an output voltage of said generator;

charging abnormality warning means, connected to said generator output voltage detecting means, for detecting a charging abnormality and producing an indication to inform an operator of the charging abnormality, including means for receiving a second predetermined voltage lower than said first reference voltage and comparing the generator output voltage detected by said generator output voltage detecting means therewith, and means coupled to said comparing means of said voltage control means for receiving a first signal indicating the battery voltage is at the first reference voltage or below and delaying said first signal for a predetermined time to produce a delayed indication, said indication produced when said generator output voltage is at or lower than said second predetermined voltage, and said delayed first signal is produced; and

change-over means receiving said control signal from said voltage control means and receiving said drive signal from said excitation control means, for driving said switching means at an amount in accordance with said output of said voltage control means, and for increasing an amount of driving of said switching means to increase the current flowing through said field winding to said increased rate higher than said first rate to thereby increase the generator output voltage to exceed the second predetermined value within the predetermined time by controlling said switching means using the control signal of said voltage control means in place of the control signal of said excitation control means, when the generator output voltage drops to the second predetermined value and below and the battery voltage drops to the first predetermined value and below, said change-over means performing a change-over operation to control said switching means using a control signal of said voltage control means in place of the control signal of said excitation control means for a predetermined time, when the output voltage of said generator drops to the second predetermined voltage and below.

5. A charging control apparatus for a vehicle generator having a stator winding and a field winding and driven by an engine to generate an output voltage for charging a battery, said apparatus comprising:

switching means, connected to said field winding, for controlling a current flowing through said field winding;

means for monitoring a voltage of said battery;

voltage control means, responsive to said voltage from said monitoring means, and connected to said switching means, for receiving a first reference voltage and comparing said battery voltage with said first reference voltage, and outputting a control signal which controls an ON/OFF state of said switching means at a first rate to maintain the battery voltage at a first predetermined value;

excitation control means, for producing a drive signal for said switching means that will increase the current flowing through said field winding to an increased rate higher than said first rate;

generator output voltage detecting means connected to an output of said generator, which detects an output voltage of said generator;

charging abnormality warning means, connected to said generator output voltage detecting means, for detecting a charging abnormality and producing an indication to inform an operator of the charging abnormality, including means for receiving a second predetermined voltage lower than said first reference voltage and comparing the generator output voltage detected by said generator output voltage detecting means therewith, and means coupled to said comparing means of said voltage control means for receiving a first signal indicating the battery voltage is at the first predetermined value or below and delaying said first signal for a predetermined time to produce a delayed first signal, said indication produced when said generator output voltage is at or lower than said second predetermined voltage, and said delayed first signal is produced; and

change-over means, receiving outputs of said excitation control means, said voltage control means and said generator output voltage detecting means, for driving said switching means using the control signal of said voltage control means in place of the control signal of said excitation control means when the generator output voltage drops to a third predetermined value and below, said change over means including means for comparing the generator output voltage from said generator output voltage detecting means with said third predetermined voltage which is higher than the second predetermined voltage but lower than the first reference voltage.

6. A charging control apparatus for a vehicle generator having a stator winding and a field winding and driven by an engine to generate an output voltage for charging a battery, said apparatus comprising:

switching means, connected to said field winding, for controlling a current flowing through said field winding;

means for monitoring a voltage of said battery;

voltage control means, responsive to said voltage from said monitoring means, and connected to said switching means for receiving a first reference voltage and comparing said battery voltage with said first reference voltage, and for generating a control signal for controlling said switching means to gradually increase the current flowing through said field winding at a first rate to thereby maintain the battery voltage at the first predetermined value when the battery voltage drops lower than the first predetermined value;

generator output voltage detecting means connected to an output of said generator, for detecting an output voltage for said generator;

charging abnormality warning means connected to said generator output voltage detecting means, for detecting a charging abnormality and producing an indication to inform an operator of the charging abnormality, including means for receiving a second predetermined voltage lower than said first reference voltage and comparing the generator output voltage detected by said generator output voltage detecting means therewith, and means coupled to said comparing means of said voltage control means for receiving a first signal indicating the battery voltage is at the first predetermined value or below and delaying said first signal for a predetermined time to produce a delayed first signal, said indication produced when said generator output voltage is at or lower than said second predetermined voltage, and said delayed first signal is produced; and

erroneous operation preventing means for preventing an erroneous operation of said charging abnormality warning means from occurring while the control signal of said voltage control means is outputted, even when the occurrence of a charging abnormality is detected.

8. An apparatus as in claim 6 wherein said gradual control by said voltage control means is by adjustment of its duty cycle.