Electric power generating system for vehicle

• US 20050258807A1
• Filed: 05/17/2005
• Published: 11/24/2005
• Est. Priority Date: 05/18/2004
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Yanagi, Mitsunori
• Granted Patent: US 7,199,559 B2
• Time in Patent Office: Days
• US Class Current: 322/33
• CPC Class Codes: H02H 5/04 responsive to abnormal temperature specially adapted for electric machines H02H7/0852
• CPC Class Codes: H02H 7/06 for dynamo-electric generators; for synchronous capacitors
• CPC Class Codes: H02P 29/02 Providing protection against overload without automatic interruption of supply protection against faults of stepper motors H02P8/36
• CPC Class Codes: H02P 9/48 Arrangements for obtaining a constant output value at varying speed of the generator, e.g. on vehicle H02P9/04 - H02P9/46 take precedence

Abstract

An electric power generating system for a vehicle includes a generator having a field coil, a voltage regulator, a temperature sensor for sensing temperature of the voltage regulator, a field current restricting circuit that directly restricts field current if temperature of the voltage regulator becomes higher than a maximum level and a device that prevents temperature of the voltage regulator from further rising without directly restricting field current if temperature of the voltage regulator becomes a warning level that is lower than the maximum level.

Claims

1. An electric power generating system for a vehicle comprising:

a generator including a field coil;

a voltage regulator for controlling output voltage of said generator, said voltage including an overheat control circuit for controlling field current supplied to the field coil if temperature of said voltage regulator becomes higher than a first threshold value;

a temperature sensor for sensing temperature of said voltage regulator;

cooling means for cooling said voltage regulator; and

control means for operating said cooling means if temperature of said voltage regulator becomes higher than a second threshold value that is lower than the first threshold value.

2. The electric power generating system as claimed in claim 1,

wherein said cooling means comprises a motor-driven cooling fan.

3. The electric power generating system as claimed in claim 2,

wherein said motor-driven cooling fan is disposed near an engine to also cool engine coolant.

4. An electric power generating system for a vehicle comprising:

a generator including a field coil;

a voltage regulator for controlling output voltage of said generator, said voltage including an overheat control circuit for controlling field current supplied to the field coil if temperature of said voltage regulator becomes higher than a first threshold value;

a temperature sensor for sensing temperature of said voltage regulator;

a plurality of electric loads connected to said generator; and

control means for turning off a portion of said plurality of electric loads if temperature of said voltage regulator becomes higher than a second threshold value that is lower than the first threshold value.

5. The electric power generating system as claimed in claim 4,

wherein said portion of said plurality of electric loads comprises an electric load that does not directly affect a vehicle driving condition.

6. The electric power generating system as claimed in claim 5,

wherein said portion of said plurality of electric loads comprises one of an audio device and a seat heater.

7. An electric power generating system for a vehicle comprising:

a generator including a field coil;

a voltage regulator for controlling output voltage of said generator;

a temperature sensor for sensing temperature of said voltage regulator;

first means, connected to said voltage regulator and said temperature sensor, for directly restricting field current supplied to the field coil if temperature of said voltage regulator becomes higher than a first threshold value; and

second means, connected to said temperature sensor, for preventing temperature of said voltage regulator from further rising without directly restricting field current if temperature of said voltage regulator becomes higher than a second threshold value that is lower than the first threshold value.

8. The electric power generating system as claimed in claim 7,

wherein said second means comprises a motor-driven cooling fan that cools said voltage regulator when the temperature of said voltage regulator becomes higher than the second threshold value.

9. The electric power generating system as claimed in claim 7,

wherein said second means comprises means for turning off an electric load if temperature of said voltage regulator becomes higher than the second threshold value.