Traction control system for a hybrid electric vehicle

• US 6,263,267 B1
• Filed: 05/09/2000
• Issued: 07/17/2001
• Est. Priority Date: 05/09/2000
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Kuang, Ming Lang, Anthony, Joseph William
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/567,679
• Time in Patent Office: 434 Days
• Field of Search: 701/22, 701/101, 180/65.1, 180/65.2, 180/65.3, 180/65.8, 180/165, 318/139
• US Class Current: 701/22
• CPC Class Codes: B60K 1/04 of the electric storage means for propulsion exchanging batteries for electric propulsion of vehicles B60L53/80; for auxiliary purposes only B60R16/04; supplying batteries to, or removing batteries from, vehicles B60S5/06
• CPC Class Codes: B60K 28/16 responsive to, or preventing, skidding of wheels brake control systems for vehicle drive stability B60T8/1755; arrangements responsive to a speed condition for adjusting wheel braking force B60T8/32; control of vehicle driving stability otherwise than by controlling the propulsion unit only B60W30/02; preventing wheel slippage by reducing power in rail vehicles B61C15/00
• CPC Class Codes: B60K 5/04 with the engine main axis, e.g. crankshaft axis, transversely to the longitudinal centre line of the vehicle
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 2710/105 Output torque
• 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

Abstract

An electric motor system for reducing drive wheel torque on a hybrid electric vehicle includes an internal combustion engine, an electric motor, a transmission, and a controller. The internal combustion engine is located in the hybrid electric vehicle and generates an engine torque. The electric motor is coupled to the internal combustion engine and generates and electric motor torque. Both the engine and motor are coupled to the transmission that uses the combined torque from both the engine and motor to generate drive wheel torque on a drive wheel. The vehicle system controller is coupled to the electric motor and senses any traction control events. When a traction control event occurs the controller commands the electric motor to reduce the drive wheel torque by reducing the electric motor torque.

Claims

1. An electric motor system to reduce drive wheel torque in a hybrid electric vehicle comprising:

an internal combustion engine located in said hybrid electric vehicle, said internal combustion engine generating an engine torque;

an electric motor located in said hybrid electric vehicle and coupled to said internal combustion engine, said electric motor generating electric motor torque;

a transmission located in said hybrid electric vehicle and coupled to said internal combustion engine and said electric motor, said transmission receiving said engine torque and said electric motor torque, said transmission generating drive wheel torque on a drive wheel; and

a vehicle system controller located in said hybrid electric vehicle and coupled to said electric motor, said vehicle system controller including control logic operative to sense a traction control event and reduce said drive wheel torque by reducing said electric motor torque, wherein said electric motor torque during said traction control event is defined by $T_m=\left[\frac{\mathrm{tc}<br><br>\_<br><br>\mathrm{tq}}{\mathrm{GRRAT1}·<br><br>\mathrm{FDR}}-T_e\right].$

2. An electric motor system to reduce drive wheel torque in a hybrid electric vehicle comprising:

an internal combustion engine located in said hybrid electric vehicle, said internal combustion engine generating an engine torque;

an electric motor located in said hybrid electric vehicle and coupled to said internal combustion engine, said electric motor generating electric motor torque;

a transmission located in said hybrid electric vehicle and coupled to said internal combustion engine and said electric motor, said transmission receiving said engine torque and said electric motor torque, said transmission generating drive wheel torque on a drive wheel; and

a vehicle system controller located in said hybrid electric vehicle and coupled to said electric motor, said vehicle system controller including control logic operative to sense a traction control event and reduce said drive wheel torque by reducing said electric motor torque, wherein said engine torque during said traction control event is defined by T<sub>e—

red</sub>(tp)=T<sub>m—

act</sub>−

T_m.

3. A traction control system comprising:

a hybrid electric vehicle having an electric motor system for reducing torque to a drive wheel, said electric motor system comprising;

an internal combustion engine located in said hybrid electric vehicle, said internal combustion engine generating an engine torque;

an electric motor located in said hybrid electric vehicle and coupled to said internal combustion engine, said electric motor generating electric motor torque;

a transmission located in said hybrid electric vehicle and coupled to said internal combustion engine and said electric motor, said transmission receiving said engine torque and said electric motor torque, said transmission generating drive wheel torque on a drive wheel; and

a vehicle system controller located in said hybrid electric vehicle and coupled to said electric motor, said vehicle system controller including control logic operative to sense a traction control event and reduce said drive wheel torque by reducing said electric motor torque, wherein said electric motor torque during said traction control event is defined by $T_m=\left[\frac{\mathrm{tc}<br><br>\_<br><br>\mathrm{tq}}{\mathrm{GRRAT1}·<br><br>\mathrm{FDR}}-T_e\right].$

4. A traction control system comprising:

a hybrid electric vehicle having an electric motor system for reducing torque to a drive wheel, said electric motor system comprising;

an internal combustion engine located in said hybrid electric vehicle, said internal combustion engine generating an engine torque;

an electric motor located in said hybrid electric vehicle and coupled to said internal combustion engine, said electric motor generating electric motor torque;

a transmission located in said hybrid electric vehicle and coupled to said internal combustion engine and said electric motor, said transmission receiving said engine torque and said electric motor torque, said transmission generating drive wheel torque on a drive wheel; and

a vehicle system controller located in said hybrid electric vehicle and coupled to said electric motor, said vehicle system controller including control logic operative to sense a traction control event and reduce said drive wheel torque by reducing said electric motor torque, wherein said engine torque during said traction control event is defined by T<sub>e—

red</sub>(tp)=T<sub>m—

act</sub>−

T_m.

5. A method of reducing torque to a drive wheel for a hybrid electric vehicle, said method comprising the steps of:

generating an engine torque;

generating electric motor torque;

generating drive wheel torque on a drive wheel, said drive wheel torque being approximately the sum of said engine torque and said electric motor torque by a factor of a transmission gear ratio and final drive ratio;

sensing a traction control event; and

reducing said drive wheel torque by reducing said electric motor torque.

6. The method of reducing torque to a drive wheel for a hybrid electric vehicle as recited in claim 5, wherein said electric motor torque is defined as $T_m=[\frac{\mathrm{tc}}{}$

_

tqGRRAT1·

FDR-Te].

7. The method of reducing torque to a drive wheel for a hybrid electric vehicle as recited in claim 5, wherein said engine torque is defined as T_e—

_red(tP)=T<sub>m—

act</sub>−

T_m.