METHOD FOR DETERMINING INERTIA EFFECTS FOR A HYBRID POWERTRAIN SYSTEM

• US 20090118919A1
• Filed: 09/20/2008
• Published: 05/07/2009
• Est. Priority Date: 11/04/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Original Assignee: BMW AG (Bayerische Motoren Werke AG), Daimler AG (Mercedes-Benz Group AG), GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust), Chrysler LLC (Stellantis NV)
• Inventors: Heap, Anthony H., Kim, Kee Yong
• Granted Patent: US 8,504,259 B2
• Time in Patent Office: Days
• US Class Current: 701/54
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/115 with planetary gears
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2050/0022 Gains, weighting coefficients or weighting functions
• CPC Class Codes: B60W 2050/0031 Mathematical model of the vehicle
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/0695 Inertia
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2510/104 Output speed
• CPC Class Codes: B60W 2510/1045 Output speed change rate
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 : Brake pedal position
• CPC Class Codes: B60W 2710/0677 : Engine power
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/1011 : Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2710/1016 : Input speed change rate
• CPC Class Codes: B60W 2710/1038 : Output speed
• CPC Class Codes: B60W 2710/1055 : Output torque change rate
• CPC Class Codes: B60W 2710/1061 : Output power
• CPC Class Codes: B60W 40/105 : Speed
• CPC Class Codes: B60W 50/04 : Monitoring the functioning of the control system
• CPC Class Codes: F16H 2037/0866 : Power split variators with distributing differentials, with the output of the CVT connected or connectable to the output shaft
• CPC Class Codes: F16H 2037/102 : the input or output shaft of the transmission is connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/104 : Power split variators with one end of the CVT connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/106 : with switching means to provide two variator modes or ranges
• CPC Class Codes: F16H 3/728 : with means to change ratio in the mechanical gearing
• CPC Class Codes: Y02T 10/40 : Engine management systems
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility

Abstract

A method for controlling a hybrid powertrain system based upon determined inertial effects for a continuously variable operating range state includes monitoring an operator torque request and a rotational speed of the output member, determining an inertial effect on an input speed of the input member for a continuously variable operating range state, and controlling motor torque outputs from the electric machines to meet the operator torque request based upon the inertial effect on the input speed of the input member.

Claims

1. Method for controlling a hybrid transmission including torque generating machines and an energy storage device connected thereto, the hybrid transmission device configured to transfer power between an input member and an output member and the torque generating machines, the method comprising:

operating the hybrid transmission in a continuously variable operating range state;

monitoring an operator torque request and a rotational speed of the output member;

determining an inertial effect on an input speed of the input member for the continuously variable operating range state; and

controlling torque outputs from the torque generating machines to meet the operator torque request based upon the inertial effect on the input speed of the input member.

2. The method of claim 1, further comprising:

determining a preferred input speed;

determining an inertial effect on the preferred input speed of the input member;

adjusting input power based upon the inertial effect on the preferred input speed of the input member; and

controlling torque outputs from the torque generating machines based upon the adjusted input power.

3. The method of claim 1, further comprising:

determining acceleration of the output member based upon the rotational speed of the output member; and

determining the inertial effect based upon the acceleration of the output member, a time-based derivative of the operator torque request, a partial derivative of the preferred input speed with respect to the rotational speed of the output member, and a partial derivative of the preferred input speed with respect to the operator torque request.

4. The method of claim 3, wherein the inertial effect comprises a sum of a product of the acceleration of the output member and the rate the preferred input speed changes with respect to the rotational speed of the output member, and a product of the time-based derivative of the operator torque request and a rate the preferred input speed changes with respect to the operator torque request.

5. The method of claim 3, further comprising

iteratively generating a pair of parametric values for the rotational speed of the output member and the operator torque request for a predetermined number of iterations;

determining a plurality of preferred input speeds for each of the iteratively generated pair of parametric values;

determining the partial derivative of the preferred input speed with respect to the rotational speed of the output member for each of the iteratively generated pairs of parametric values based upon a corresponding preferred input speed and a change in rotational speed of the output member over a predetermined time interval; and

determining the partial derivative of the preferred input speed with respect to the operator torque request for each of the iteratively generated pairs of parametric values based upon a corresponding preferred input speed and a change in the operator torque request over a predetermined time interval.

6. The method of claim 5, further comprising:

storing the plurality of the preferred input speeds in a first lookup table;

storing each of the partial derivatives of the preferred input speed changes with respect to the rotational speed of the output member in a second lookup table according to corresponding iteratively generated pairs of parametric values; and

storing each of the partial derivatives of the preferred input speed changes with respect to the operator torque request in a third lookup table according to corresponding iteratively generated pairs of parametric values.

7. The method of claim 6, wherein the first, second and third lookup tables are indexed by the iteratively generated pairs of parametric values.

8. The method of claim 6, further comprising:

locating a pair of parametric values corresponding to the rotational speed of the output member and the operator torque request in the second and third lookup tables;

determining the rate the preferred input speed changes with respect to the rotational speed of the output member corresponding to the located pair of parametric values; and

determining the rate the preferred input speed changes with respect to the operator torque request corresponding to the located pair of parametric values.

9. The method of claim 1, further comprising:

determining acceleration of the output member based upon the rotational speed of the output member;

determining output power of the output member; and

determining the inertial effect based upon the acceleration of the output member, a partial derivative of the preferred input speed with respect to the rotational speed of the output member, a time-based derivative of the output power, and a partial derivative of the preferred input speed with respect to the output power.

10. The method of claim 9, further comprising:

determining a product of the time-based derivative of the output power and the partial derivative of the preferred input speed with respect to the output power; and

adding said product with a product of a difference between the partial derivative of the preferred input speed with respect to the rotational speed of the output member and a product of the operator torque request and the partial derivative of the preferred input speed with respect to the output power and the acceleration of the output member.

11. The method of claim 10, further comprising

iteratively generating a pair of parametric values for the rotational speed of the output member and the operator torque request for a predetermined number of iterations;

determining a plurality of preferential input speeds for each of the iteratively generated pair of parametric values;

determining the partial derivative of the preferred input speed with respect to the rotational speed of the output member for each of the iteratively generated pairs of parametric values based upon a corresponding preferred input speed and a change in rotational speed of the output member over a predetermined time interval; and

determining the partial derivative of the preferred input speed with respect to the output power for each of the iteratively generated pairs of parametric values based upon a corresponding preferred input speed and a change in the output power over a predetermined time interval.

12. The method of claim 11, further comprising:

storing the plurality of the preferred input speeds in a first lookup table;

storing each of the determined rate the preferred input speed changes with respect to the rotational speed of the output member in a second lookup table according to corresponding iteratively generated pairs of parametric values; and

storing each of the determined rate the preferred input speed changes with respect to the output power in a third lookup table according to corresponding iteratively generated pairs of parametric values.

13. The method of claim 12, wherein the first, second and third lookup tables are indexed by the iteratively generated pairs of parametric values.

14. The method of claim 12, further comprising:

locating a pair of parametric values corresponding to the rotational speed of the output member and the output power in the second and third lookup tables;

determining the rate the preferred input speed changes with respect to the rotational speed of the output member corresponding to the located pair of parametric values; and

determining the rate the preferred input speed changes with respect to the output power corresponding to the located pair of parametric values.

15. Method for controlling a powertrain system including an engine coupled to an input member of an electro-mechanical transmission device including electric machines and an energy storage device connected thereto, the electro-mechanical transmission device selectively operative in one of a plurality of operating range states to transfer power between the input member and an output member and the electric machines, the method comprising:

monitoring an operator torque request and a rotational speed of the output member;

determining an inertial effect on an input speed of the input member for a continuously variable operating range state; and

controlling motor torque outputs from the electric machines to meet the operator torque request based upon the inertial effect on the input speed of the input member.

16. The method of claim 15, further comprising:

determining a preferred input speed;

determining an inertial effect on the preferred input speed of the input member;

adjusting input power based upon the inertial effect on the preferred input speed of the input member; and

controlling motor torque outputs from the electric machines to meet the operator torque request based upon the adjusted input power.

17. The method of claim 15, further comprising:

determining acceleration of the output member based upon the rotational speed of the output member;

determining the inertial effect based upon the acceleration of the output member, a time-based derivative of the operator torque request, a partial derivative of the preferred input speed with respect to the rotational speed of the output member, and a partial derivative of the preferred input speed with respect to the operator torque request.

18. The method of claim 15, further comprising:

determining acceleration of the output member based upon the rotational speed of the output member;

determining output power of the output member; and

determining the inertial effect based upon the acceleration of the output member, a partial derivative of the preferred input speed with respect to the rotational speed of the output member, a time-based derivative of the output power, and a partial derivative of the preferred input speed with respect to the output power.

19. The method of claim 18, further comprising:

determining a product of the time-based derivative of the output power and the partial derivative of the preferred input speed with respect to the output power;

adding said product with a product of a difference between the partial derivative of the preferred input speed with respect to the rotational speed of the output member and a product of the operator torque request and the partial derivative of the preferred input speed with respect to the output power and the acceleration of the output member;

iteratively generating a pair of parametric values for the rotational speed of the output member and the operator torque request for a predetermined number of iterations;

determining a plurality of preferential input speeds for each of the iteratively generated pair of parametric values;

determining the partial derivative of the preferred input speed with respect to the rotational speed of the output member for each of the iteratively generated pairs of parametric values based upon a corresponding preferred input speed and a change in rotational speed of the output member over a predetermined time interval; and

determining the partial derivative of the preferred input speed with respect to the output power for each of the iteratively generated pairs of parametric values based upon a corresponding preferred input speed and a change in the output power over a predetermined time interval.

20. The method of claim 19, further comprising:

storing the plurality of the preferred input speeds in a first lookup table;

storing each of the partial derivatives of the preferred input speed changes with respect to the rotational speed of the output member in a second lookup table according to corresponding iteratively generated pairs of parametric values; and

storing each of the partial derivatives of the preferred input speed changes with respect to the output power in a third lookup table according to corresponding iteratively generated pairs of parametric values.