Internal combustion engine start controller

• US 20070175429A1
• Filed: 01/26/2007
• Published: 08/02/2007
• Est. Priority Date: 01/31/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Sato, Eiji, Oki, Ryoji, Takahashi, Hidenori, Yanagida, Eiji
• Granted Patent: US 7,594,491 B2
• Time in Patent Office: Days
• US Class Current: 123/179.140
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 2210/12 Buck converters
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2240/525 Temperature of converter or components thereof
• CPC Class Codes: B60L 2240/526 Operating parameters
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0859 specially adapted to the type of the starter motor or integrated into it
• CPC Class Codes: F02N 11/0866 : comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 11/087 : Details of the switching means in starting circuits, e.g. relays or electronic switches
• CPC Class Codes: F02N 2011/0874 : characterised by said switch being an electronic switch
• CPC Class Codes: F02N 2011/0888 : DC/DC converters
• CPC Class Codes: F02N 2011/0896 : Inverters for electric machines, e.g. starter-generators
• CPC Class Codes: F02N 2200/064 : Battery temperature
• CPC Class Codes: F02N 2300/108 : Duty cycle control or pulse width modulation [PWM]
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

An internal combustion engine start controller in a vehicle that includes: a power source; an internal combustion engine that is started by using electric power supplied from the power source; a first motor; and a first electric power converter that is constructed so as to be able to perform electric power conversion between the power source and the first motor through switching control of power semiconductor elements is provided. The start controller includes: a start detecting device for detecting whether the engine is in a starting operation; and a first frequency setting device that, when the engine is in a starting operation, sets a switching frequency of the first electric power converter to a frequency lower than that used when the engine is not in a starting operation.

Claims

1. An internal combustion engine start controller in a vehicle that includes:

a power source;

an internal combustion engine that is started by using electric power supplied from the power source;

a first motor; and

a first electric power converter that is constructed so as to be able to perform electric power conversion between the power source and the first motor through switching control of power semiconductor elements, the controller comprising;

a start detecting device for detecting whether the engine is in a starting operation; and

a first frequency setting device that, when the engine is in a starting operation, sets a switching frequency of the first electric power converter to a frequency lower than that used when the engine is not in a starting operation.

2. The internal combustion engine start controller according to claim 1, wherein

the first motor is configured so as to be able to produce power for starting the engine when the engine is in a starting operation, and so as to have an operating period of time other than when the engine is in a starting operation.

3. The internal combustion engine start controller according to claim 2, wherein

the first motor is configured so as to be able to generate electricity by using a rotational force produced by the engine when the engine is in operation, and

the first electric power converter is controlled so as to convert electric power generated by the first motor to electric power with which it is possible to charge the power source.

4. The internal combustion engine start controller according to claim 3, further comprising:

a low temperature detector for detecting a low temperature state of the power source based on a detected temperature of the power source, wherein,

even when the engine is in a starting operation, if the low temperature state of the power source is not detected by the low temperature detector, the first frequency setting device sets the switching frequency of the first electric power converter to substantially the same frequency as that used when the engine is not in a starting operation.

5. The internal combustion engine start controller according to claim 4, wherein,

when the engine is in a starting operation, if the low temperature state of the power source is detected by the low temperature detector, the first frequency setting device sets the switching frequency of the first electric power converter to a frequency lower than that used when the engine is not in a starting operation, according to the detected temperature of the power source.

6. The internal combustion engine start controller according to claim 1, further comprising:

a low temperature detector for detecting a low temperature state of the power source based on a detected temperature of the power source, wherein,

even when the engine is in a starting operation, if the low temperature state of the power source is not detected by the low temperature detector, the first frequency setting device sets the switching frequency of the first electric power converter to substantially the same frequency as that used when the engine is not in a starting operation.

7. The internal combustion engine start controller according to claim 1, wherein

the vehicle further includes:

a second motor that is driven by using the electric power supplied from the power source and is connected to a drive shaft that is different from a shaft to that the first motor is connected; and

a second electric power converter constructed so as to be able to perform electric power conversion between the power source and the second motor through switching control of the power semiconductor elements, and

the start controller further comprises;

a second frequency setting device that, when the engine is in a starting operation, sets a switching frequency of the second electric power converter to a frequency lower than that used when the engine is not in a starting operation.

8. The internal combustion engine start controller according to claim 7, further comprising:

a low temperature detector for detecting a low temperature state of the power source based on a detected temperature of the power source, wherein,

even when the engine is in a starting operation, if the low temperature state of the power source is not detected by the low temperature detector, the first and second frequency setting devices respectively set the switching frequency of the first electric power converter and the switching frequency of the second electric power converter to substantially the same frequencies as those used when the engine is not in a starting operation.

9. The internal combustion engine start controller according to claim 8, wherein,

when the engine is in a starting operation, if the low temperature state of the power source is detected by the low temperature detector, the first and second frequency setting devices determine whether to set the switching frequency of the first electric power converter and the switching frequency of the second electric power converter, respectively, to frequencies lower than those used when the engine is not in a starting operation, based on the detected temperature of the power source.

10. The internal combustion engine start controller according to claim 7, wherein

power output from the second motor is transmitted to the drive shaft of the vehicle.

11. The internal combustion engine start controller according to claim 10, further comprising:

a low temperature detector for detecting a low temperature state of the power source based on a detected temperature of the power source, wherein,

even when the engine is in a starting operation, if the low temperature state of the power source is not detected by the low temperature detector, the first and second frequency setting devices respectively set the switching frequency of the first electric power converter and the switching frequency of the second electric power converter to substantially the same frequencies as those used when the engine is not in a starting operation.

12. The internal combustion engine start controller according to claim 11, wherein

when the engine is in a starting operation, if the low temperature state of the power source is detected by the low temperature detector, the first and second frequency setting devices determine whether to set the switching frequency of the first electric power converter and the switching frequency of the second electric power converter, respectively, to frequencies lower than those used when the engine is not in a starting operation, based on the detected temperature of the power source.