Control system for vehicle generator and control method therefor

• US 5,808,367 A
• Filed: 12/11/1996
• Issued: 09/15/1998
• Est. Priority Date: 04/11/1995
• Status: Expired due to Fees

• Current Assignee: Hitachi Car Engineering Company Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Original Assignee: Hitachi Car Engineering Company Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Inventors: Akagi, Yoshihiko, Fujishita, Masakatsu
• Primary Examiner(s): Dougherty, Thomas M.
• Assistant Examiner(s): Ponomarenko, Nicholas
• Application Number:
  US08/750,505
• Time in Patent Office: 643 Days
• Field of Search: 290/40 A, 290/40 B, 290/40 C, 290/40 R, 322/28, 322/29, 123/339
• US Class Current: 290/40.00C
• CPC Class Codes: F02D 2200/503 Battery correction, i.e. corrections as a function of the state of the battery, its output or its type
• CPC Class Codes: F02D 31/005 by controlling a throttle by-pass
• CPC Class Codes: F02D 41/083 taking into account engine load variation, e.g. air-conditionning
• CPC Class Codes: H02J 7/1446 in response to parameters of a vehicle
• CPC Class Codes: H02P 9/04 Control effected upon non-electric prime mover and dependent upon electric output value of the generator
• CPC Class Codes: H02P 9/107 for limiting effects of overloads
• CPC Class Codes: H02P 9/30 using semiconductor devices
• CPC Class Codes: H02P 9/305 controlling voltage H02P9/302 takes precedence
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A method for controlling a vehicle generator, by obtaining a first correction volume of an opening of an ISC valve (ISCPI) based on a deviation of a rotation number of an internal combustion engine from a target rotation number, obtaining a driving volume of an excitation coil of a generator based on a deviation of a battery voltage from a target voltage, and obtaining a second correction volume of an opening of the ISC valve (EL) that takes account of an electrical load variation based on a driving volume of the excitation coil and a rotation number of the internal combustion engine, to obtain a driving volume of the ISC valve (ISCDTY) based on the first and second correction volumes of the opening of the ISC valve.

Claims

1. A control system for a vehicle generator, comprising:

an internal combustion engine mounted on a vehicle;

an operating unit for controlling a driving of said internal combustion engine;

driving status detecting means for detecting a driving status of said internal combustion engine by detecting at least a rotation number of said internal combustion engine, an opening of a throttle valve and a temperature of a cooling water;

intake air quantity adjusting means for adjusting a quantity of an intake air during an idling;

a generator driven by said internal combustion engine, for generating power;

an excitation coil incorporated in said generator, for controlling a generation volume;

means for driving said excitation coil;

a battery to be charged by power generated by said generator; and

means for detecting a voltage of said battery, wherein said operating unit includes;

means for setting a driving volume of said intake air quantity adjusting means;

means for calculating a target generation voltage according to a driving status of said internal combustion engine;

means for calculating driving volume (ALTDTY,

     224) of said excitation coil so that a voltage of said battery comes close to said target generation voltage by comparing said target generation voltage with said battery voltage; and

means for correcting a driving volume of said intake air quantity adjusting means by a first correction volume (ISCPI,

     209) based on a rotation number of said internal combustion engine and a second correction volume (EL,

     210) based on a driving volume of said excitation coil and said detected driving status.

2. A control system for a vehicle generator according to claim 1, wherein said means for correcting said intake air quantity adjusting means includes means (210) for multiplying a driving volume of said excitation coil with a value obtained from load characteristics of said internal combustion engine.

3. A control system for a vehicle generator according to claim 1, further including means (225, 226) for changing a speed of changing a driving volume of said excitation coil according to a detected driving status.

4. A control system for a vehicle generator according to claim 3, wherein said means for changing a speed of changing a driving volume of said excitation coil includes:

means (225) for detecting an electrical load status; and

means (226) for changing a speed of changing a driving volume of said excitation coil based on said detected electrical load status.

5. A control system for a vehicle generator according to claim 3, wherein said means for changing a speed of changing a driving volume of said excitation coil includes means for setting a speed of increasing a driving volume of said excitation coil to be smaller than a maximum speed of decreasing a driving volume of said excitation coil.

6. A control system for a vehicle generator according to claim 1, further including:

failure detecting means (301) for detecting a failure of said operating unit; and

auxiliary control means (302) for controlling said internal combustion engine in place of said operating unit when said failure detecting means detected a failure of said operating unit, and said auxiliary control means includes means (SW1) for interrupting a current of said excitation coil when a battery voltage has become a predetermined value or above.

7. A control system for a vehicle generator according to claim 1, further including:

means (212) for detecting whether it has become necessary to raise a voltage of said battery; and

means (213,

     214) for raising a voltage of said battery by increasing a target rotation number of said internal combustion engine when a driving volume of said excitation coil is at least a predetermined value at a time when it becomes necessary to raise a voltage of said battery.

8. A control system for a vehicle generator according to claim 1, wherein said means for calculating said target generation voltage includes:

means for sampling a temperature of a cooling water of said internal combustion engine at every predetermined time;

means for carrying out a weighted average processing of a result obtained by said sampling;

means for estimating a temperature of said battery liquid from a value obtained by said weighted average processing; and

means (FIG.

     8) for correcting said target generation voltage based on a relation between an estimated temperature of said battery liquid and a charging voltage.

9. A control system for a vehicle generator according to claim 8, wherein said means for estimating a temperature of said battery liquid includes:

means for comparing a current temperature of a cooling water of said internal combustion engine with a memory value of a cooling water temperature after a weighted average processing stored at a time when said internal combustion engine stopped; and

means (FIG.

     17) for setting a value whichever is lower as an estimated value of a battery liquid temperature at a starting time.

10. In a control system for a vehicle generator, comprising:

an internal combustion engine mounted on a vehicle;

an operating unit for controlling a driving of said internal combustion engine;

intake air quantity adjusting means for adjusting a quantity of an intake air during an idling;

a generator driven by said internal combustion engine, for generating power;

an excitation coil incorporated in said generator, for controlling a generation volume; and

a battery to be charged by power generated by said generator, a method for controlling a vehicle generator, including;

a step (202) for obtaining a rotation number N of said internal combustion engine;

a step (207) for obtaining a target rotation number NSET of said internal combustion engine from a temperature of a cooling water;

a step (208) for obtaining a rotation number deviation .increment.N1=NSET-N;

a step (209) for setting a first correction volume of an intake air quantity during an idling based on said rotation number deviation .increment.N1;

a step (210) for setting a second correction volume (EL) of an intake air quantity during an idling based on an electrical load volume; and

a step (211) for adjusting an intake air quantity during an idling based on said first and second correction volumes.

11. A control method according to claim 10, wherein said step for setting a first correction volume of an intake air quantity includes a step for setting said first correction volume by referring to a table (FIG. 6) for showing a relation between said rotation number deviation .increment.N1 and an adjusting volume of said intake air adjusting means during an idling.

12. A control method according to claim 10, further including:

a step (223) for detecting a voltage deviation between a target generation voltage and an actual battery voltage; and

a step (224) for obtaining an excitation coil driving volume of a vehicle generator based on said voltage deviation, and said step for setting a second correction volume includes a step for obtaining said second correction volume based on said excitation coil driving volume obtained.

13. A control method according to claim 12, wherein said step for obtaining said second correction volume (EL) includes a step for obtaining said second correction volume based on the following expression:

a second correction volume=K×

ALTDTY×

B×

N where, K represents a conversion coefficient, ALTDTY represents an excitation coil driving volume, B represents a value based on load characteristics of an internal combustion engine and N represents a rotation number of said internal combustion engine.

14. A control method according to claim 13, wherein said step for obtaining said second correction volume includes a step for obtaining a torque of a generator determined from a rotation number of an internal combustion engine as a value based on load characteristics of an internal combustion engine.

15. A control method according to claim 12, further including:

a step (225) for monitoring a driving status of an internal combustion engine; and

a step (226) for controlling a speed of changing a driving volume of said excitation coil according to a driving status.

16. A control method according to claim 15, wherein said step for monitoring a driving status includes a step for monitoring a variation of an electrical load, and said step for controlling a speed of changing a driving volume of said excitation coil includes a step for limiting a speed of changing a driving volume of said excitation coil when a variation of said electrical load has exceeded a predetermined value and for controlling said excitation coil with an excitation coil driving volume obtained at said step for obtaining a driving volume of said excitation coil when a variation of said electrical load is not higher than a predetermined value.

17. A control method according to claim 15, wherein said step for monitoring a variation of an electrical load includes a step for detecting a variation of a battery voltage.

18. A control method according to claim 15, wherein said step for controlling a speed of changing a driving volume of said excitation coil includes a step for setting a speed of increasing a driving volume of said excitation coil to be smaller than a maximum speed of decreasing a driving volume of said excitation coil.

19. A control method according to claim 12, further including:

a step (212) for determining whether it is possible to increase a driving volume of said excitation coil when it becomes necessary to further raise a battery voltage; and

steps (213,

     214) for setting said target rotation number NSET to a higher value when it is not possible to increase a driving volume of said excitation coil.

20. A control method according to claim 12, wherein said step for detecting a voltage deviation of an actual battery voltage from a target generation voltage includes:

a step for sampling a temperature of a cooling water of said internal combustion engine at every predetermined time;

a step for carrying out a weighted average processing of a result obtained by said sampling;

a step (220) for estimating a temperature of said battery liquid from a value obtained by said weighted average processing; and

a step (221) for determining said target generation voltage from said estimated temperature of a battery liquid.

21. A control method according to claim 20, wherein said step for estimating a temperature of a battery liquid includes:

a step comparing a current temperature of a cooling water of said internal combustion engine with a memory value of a cooling water temperature after a weighted average processing stored at a time when said internal combustion engine stopped; and

a step (FIG.

     17) for setting a value whichever is lower as a result of said comparison as an estimated value of a battery liquid temperature at a starting time.

22. In a control system for a vehicle generator, comprising:

an internal combustion engine mounted on a vehicle;

an operating unit for controlling a driving of said internal combustion engine;

a generator driven by said internal combustion engine, for generating power;

an excitation coil incorporated in said generator, for controlling a generation volume; and

a battery to be charged by power generated by said generator, a method for controlling a vehicle generator, including;

a step (220) for obtaining a battery liquid temperature;

a step (221) for obtaining a target generation voltage of said generator based on a relation between a battery liquid temperature and a charge finishing voltage of said battery;

a step (222) for detecting a battery voltage;

a step (223) for obtaining a voltage deviation of said battery voltage from said target generation voltage; and

a step (224) for obtaining a driving volume of said excitation coil of said generator from said voltage deviation.

23. A control method according to claim 22, further including:

a step (225) for detecting a variation of an electrical load; and

a step (226) for controlling a speed of changing a driving volume of said excitation coil when a variation of said electrical load has exceeded a predetermined value.

24. A control method according to claim 23, wherein said step for detecting a variation of an electrical load includes a step for detecting a variation of a voltage of said battery.

25. A control method according to claim 23, wherein said step for limiting a speed of changing a driving volume of said excitation coil includes a step for setting a speed of increasing a driving volume of said excitation coil to be smaller than a maximum speed of decreasing a driving volume of said excitation coil.

26. A control method according to claim 23, wherein said step for limiting a speed of increasing a driving volume of said excitation coil includes, when an intake air quantity has been set to zero by said intake air quantity adjusting means:

a step for setting a limit value of a speed of changing a driving volume of said excitation coil to a first value when a rotation number of said internal combustion engine is higher than a predetermined value;

a step for setting a limit value of a speed of changing a driving volume of said excitation coil to a second value when a rotation number of said internal combustion engine is not higher than a predetermined value and an electrical load exceeds a predetermined value; and

a step for setting a limit value of a speed of changing a driving volume of said excitation coil to a third value when a rotation number of said internal combustion engine is not higher than a predetermined value and an electrical load is not higher than a predetermined value,

where, said first value>

said second value>

said third value (FIG.

     10).

27. In a control system for a vehicle generator, comprising:

an internal combustion engine mounted on a vehicle;

an operating unit for controlling a driving of said internal combustion engine;

intake air quantity adjusting means for adjusting a quantity of an intake air during an idling;

a generator driven by said internal combustion engine, for generating power;

an excitation coil incorporated in said generator, for controlling a generation volume; and

a battery to be charged by power generated by said generator, a method for controlling a vehicle generator (FIG.

     10), including;

a step of setting a limit value of a speed of changing a driving volume of said excitation coil to a first value when a rotation number of said internal combustion engine is higher than a predetermined value;

a step for setting a limit value of a speed of changing a driving volume of said excitation coil to a second value when a rotation number of said internal combustion engine is not higher than a predetermined value and an electrical load exceeds a predetermined value; and

a step for setting a limit value of a speed of changing a driving volume of said excitation coil to a third value when a rotation number of said internal combustion engine is not higher than a predetermined value and an electrical load is not higher than a predetermined value,

where, said first value>

said second value>

said third value.

28. A method for controlling a vehicle generator, including:

a step (209) for obtaining a first correction volume of an opening of an ISC valve based on a deviation of a rotation number of an internal combustion engine from a target rotation number;

a step (224) for obtaining a driving volume of an excitation coil of a generator based on a deviation of a battery voltage from a target voltage;

a step (210) for obtaining a second correction volume of an opening of said ISC valve based on a driving volume of said excitation coil and a rotation number of said internal combustion engine; and

a step (211) for obtaining a driving volume of said ISC valve from said first and second correction volumes of an opening of said ISC valve.