Method and apparatus to reprofile input speed during speed during speed phase during constrained conditions for a hybrid powertrain system

• US 8,170,764 B2
• Filed: 10/13/2008
• Issued: 05/01/2012
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Original Assignee: Bayerische Motoren Werke AG, GM Global Technology Operations LLC (General Motors Company), Daimler AG (Mercedes-Benz Group AG), Chrysler LLC (Stellantis NV)
• Inventors: Kaminsky, Lawrence A., Sah, Jy-Jen F.
• Primary Examiner(s): Trammell, James
• Assistant Examiner(s): Shafi, Muhammad
• Application Number:
  US12/250,523
• Publication Number:
  US 20090118931A1
• Time in Patent Office: 1,296 Days
• Field of Search: 701/22, 701/35, 701/208, 701/211, 701/213, 701/300, 180/65.21, 180 651- 658, 340/995.1, 340/995.19
• US Class Current: 701/70
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• 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: 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 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 30/19 Improvement of gear change, e.g. by synchronisation or smoothing gear shift
• 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 2061/6603 characterised by changing ratio in the mechanical gearing
• CPC Class Codes: F16H 2302/00 Determining the way or trajectory to new ratio, e.g. by determining speed, torque or time parameters for shift transition
• CPC Class Codes: F16H 61/0204 for gearshift control, e.g. control functions for performing shifting or generation of shift signal
• CPC Class Codes: F16H 63/502 for smoothing gear shifts
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A method to control a powertrain including a transmission, an engine, and an electric machine includes monitoring an input speed, monitoring an output speed, upon initiation of a transmission shift, determining a plurality of input acceleration profiles for controlling the engine and electric machine during the shift, identifying an input acceleration constraint affecting one of the input acceleration profiles, reprofiling the input acceleration profiles based upon the identified input acceleration constraint, and controlling operation of the engine and electric machine based upon the reprofiled input acceleration profiles.

Claims

1. Method for controlling a powertrain comprising an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member of said transmission, said method comprising:

monitoring an input speed of an input member of said transmission;

monitoring an output speed of said output member;

upon initiation of a transmission shift, determining a plurality of input acceleration profiles for controlling said engine and electric machine during said shift, comprising;

determining a target input speed synchronizing said input member based upon a destination gear state; and

determining said input acceleration profiles based upon transitioning said input speed from an initial input speed to said target input speed;

identifying an input acceleration constraint affecting one of said input acceleration profiles;

reprofiling said input acceleration profiles based upon said identified input acceleration constraint, comprising;

determining a new target input speed based upon said input acceleration constraint; and

reprofiling said input acceleration profiles based upon said new target input speed; and

controlling operation of said engine and electric machine based upon said reprofiled input acceleration profiles.

2. The method of claim 1, wherein said powertrain further comprises a second electric machine;

wherein determining a plurality of input acceleration profiles includes controlling said second electric machine; and

further comprising controlling operation of said second machine based upon said reprofiled input acceleration profiles.

3. The method of claim 1, further comprising:

determining a slip speed based upon said input speed and said output speed;

wherein reprofiling said input acceleration profiles, when said shift includes an inertia speed phase, utilizes said slip speed to approach a zero slip speed.

4. The method of claim 1, wherein reprofiling said input acceleration profiles further comprises changing a duration of said input acceleration profiles.

5. The method of claim 1, wherein said input acceleration profiles are divided into three phases comprising:

a first phase, wherein an input acceleration is profiled to change said input speed from an initial input speed;

a third phase, wherein said input acceleration is profiled to attenuate said input speed to a target input speed; and

a second phase bridging said first phase and said second phase;

wherein reprofiling said input acceleration profiles is based upon which phase of said input acceleration profiles are affected by said input acceleration constraint.

6. The method of claim 5, wherein reprofiling said input acceleration profiles comprises changing a duration of said second phase.

7. The method of claim 1, wherein determining said plurality of input acceleration profiles and said reprofiling said input acceleration profiles are performed in a clutch slip speed domain.

8. Apparatus for controlling a powertrain comprising an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member, said apparatus comprising:

an oncoming clutch including an input member and an output member; and

a powertrain control system, including programming to monitor an input speed of said input member,

monitor an output speed of said output member,

upon initiation of a transmission shift, determine a plurality of input acceleration profiles for controlling said engine and electric machine during said shift, comprising programming to;

determine a target input speed synchronizing said input member based upon a destination gear state; and

determine said input acceleration profiles based upon transitioning said input speed from an initial input speed to said target input speed;

monitor an input acceleration constraint affecting one of said input acceleration profiles,

reprofile said input acceleration profiles based upon said identified input acceleration constraint, comprising programming to;

determine a new target input speed based upon said input acceleration constraint; and

reprofile said input acceleration profiles based upon said new target input speed; and

control operation of said engine and electric machine based upon said reprofiled input acceleration profiles.

9. The apparatus of claim 8, wherein said powertrain control system further includes programming to

determine a plurality of input acceleration profiles for controlling a second electric machine during said shift, and

control operation of said second electric machine.

10. The apparatus of claim 8, wherein programming to reprofile said input acceleration profiles comprises programming to change a duration of said input acceleration profiles.

11. The apparatus of claim 8,

wherein said input acceleration profiles are divided into three phases comprising

a first phase, wherein an input acceleration is profiled to change said input speed from an initial input speed,

a third phase, wherein said input acceleration is profiled to attenuate said input speed to a target input speed, and

a second phase bridging said first phase and said second phase;

wherein said programming to reprofile said input acceleration profiles is based upon which phase of said input acceleration profiles are affected by said input acceleration constraint.

12. Method for controlling a powertrain comprising an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member of said transmission, said method comprising:

monitoring an input speed of an input member of said transmission;

monitoring an output speed of said output member;

determining a slip speed based upon said input speed and said output speed;

upon initiation of a transmission shift, determining a plurality of input acceleration profiles for controlling said engine and electric machine during said shift, wherein said input acceleration profiles are divided into three phases comprising;

a first phase, wherein an input acceleration is profiled to change said input speed from an initial input speed;

a third phase, wherein said input acceleration is profiled to attenuate said input speed to a target input speed; and

a second phase bridging said first phase and said second phase;

identifying an input acceleration constraint affecting one of said input acceleration profiles;

reprofiling said input acceleration profiles based upon said identified input acceleration constraint, said reprofiling comprising;

determining a recalculated target input speed based upon said output speed and a destination gear ratio; and

reprofiling said input acceleration profiles in order to attenuate said input speed to said recalculated target speed based upon which phase of said input acceleration profiles are affected by said input acceleration constraint, said reprofiling comprising changing a duration of said second phase; and

controlling operation of said engine and electric machine based upon said reprofiled input acceleration profiles;

wherein said changing a duration of said second phase comprises, when only said first phase is affected by said input acceleration constraint, changing said duration of said second phase to equal a slip speed differential that must be accomplished through said second phase divided by a rate of change of slip speed that will occur through said second phase.

13. Method for controlling a powertrain comprising an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member of said transmission, said method comprising:

monitoring an input speed of an input member of said transmission;

monitoring an output speed of said output member;

determining a slip speed based upon said input speed and said output speed;

upon initiation of a transmission shift, determining a plurality of input acceleration profiles for controlling said engine and electric machine during said shift, wherein said input acceleration profiles are divided into three phases comprising;

a first phase, wherein an input acceleration is profiled to change said input speed from an initial input speed;

a third phase, wherein said input acceleration is profiled to attenuate said input speed to a target input speed; and

a second phase bridging said first phase and said second phase;

identifying an input acceleration constraint affecting one of said input acceleration profiles;

reprofiling said input acceleration profiles based upon said identified input acceleration constraint, said reprofiling comprising;

determining a recalculated target input speed based upon said output speed and a destination gear ratio; and

reprofiling said input acceleration profiles in order to attenuate said input speed to said recalculated target speed based upon which phase of said input acceleration profiles are affected by said input acceleration constraint, said reprofiling comprising changing a duration of said second phase; and

controlling operation of said engine and electric machine based upon said reprofiled input acceleration profiles;

wherein said changing a duration of said second phase comprises, when said second phase is affected by said input acceleration constraint but said third phase is not affected by said input acceleration constraint, changing said duration of said second phase to equal a slip speed differential that must be accomplished through said second phase divided by a rate of change of slip speed that will occur through said second phase, additionally adding a portion of duration of said second phase already spent.