# US 8,187,145 B2 · Method and apparatus for clutch torque control in mode and fixed gear for a hybrid powertrain system

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,187,145 B2
- Document ID: US8187145B2
- Status: Granted
- Kind: B2
- Application number: 12/250,518
- Filed: 2008-10-13
- Published: 2009-04-30
- Granted: 2012-05-29
- Earliest claimed: 2007-10-25
- Assignees: GM Global Technology Operations LLC; Daimler AG; Chrysler Corporation; Bayerische Motoren Werke Aktiengesellschaft
- Inventors: Lawrence A. Kaminsky; Anthony H. Heap; Jy-Jen F. Sah
- Web page: https://patentgrep.com/patent/US8187145B2

## CPC

- 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)}
- B60K 6/365: with the gears having orbital motion
- B60K 6/445: Differential gearing distribution type
- B60K 6/547: the transmission being a stepped gearing
- B60W 10/02: including control of driveline clutches
- B60W 10/06: including control of combustion engines
- B60W 10/08: including control of electric propulsion units, e.g. motors or generators
- B60W 10/115: with planetary gears
- B60W 10/30: including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
- B60W 20/00: Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)}
- F16H 3/728: {with means to change ratio in the mechanical gearing}
- F16H 61/061: {using electric control means}
- B60K 1/02: comprising more than one electric motor
- B60L 2240/423: Torque
- B60L 2240/445: Temperature
- B60W 2050/0006: {Digital architecture hierarchy}
- B60W 2510/0216: Clutch engagement rate
- B60W 2510/0671: Engine manifold pressure
- B60W 2510/0676: Engine temperature
- B60W 2540/10: Accelerator pedal position
- B60W 2540/12: Brake pedal position
- B60W 2555/20: Ambient conditions, e.g. wind or rain
- B60W 2710/0605: Throttle position
- B60W 2710/0616: Position of fuel or air injector
- B60W 2710/0666: Engine torque
- B60W 2710/083: Torque
- F16H 19/06: comprising {flexible members, e.g. an} endless flexible member
- F16H 2037/0866: {Power-split transmissions with distributing differentials, with the output of the CVT connected or connectable to the output shaft}
- F16H 2037/102: {the input or output shaft of the transmission is connected or connectable to two or more differentials}
- F16H 2037/104: {Power-split transmissions with at least one end of a CVT connected or connectable to two or more differentials}
- F16H 2037/106: {with switching means to provide two variator modes or ranges}
- F16H 2342/044: Torque transmitting capability
- Y02T 10/62: Hybrid vehicles
- Y02T 10/64: Electric machine technologies in electromobility
- B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- F16H: GEARING
- B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

A method for controlling hydraulic line pressure of a hydraulic control system in 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 via selective application of a plurality of hydraulically-applied torque transfer clutches includes monitoring requirements for transmission of clutch reactive torque in one of the clutches, monitoring a hydraulic line pressure within the hydraulic control system, determining a minimum clutch torque capacity required to keep the clutch from slipping, determining a hydraulic line pressure required to create the minimum clutch torque capacity, and modulating hydraulic line pressure applied to the clutch by modulating operation of the hydraulic control system based upon the hydraulic line pressure required to create the minimum clutch torque capacity.

## Claims

### Claim 1

Method for controlling a hydraulic line pressure of a hydraulic control system in 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 via selective application of a plurality of hydraulically-applied torque transfer clutches, said method comprising:
monitoring a current output torque of said transmission;
monitoring a requested output torque command;
monitoring transmission of clutch reactive torque in each of said clutches;
adjusting a minimum clutch torque capacity as a feed-forward control based upon said clutch reactive torques and comparing said requested output torque command to said current output torque; and
controlling said hydraulic line pressure by modulating operation of said hydraulic control system based upon said minimum clutch torque capacity;
wherein said current output torque is generated by providing mechanical power from said electric machine and selectively providing mechanical power from said engine.

### Claim 2 (depends on 1)

The method of claim 1, wherein adjusting said minimum clutch torque capacity comprises:
determining a line pressure compensation factor based upon greater of one and a ratio of said requested output torque command to said current output torque;
multiplying each said clutch reactive torque for each of said clutches by said line pressure compensation factor;
identifying a critical clutch reactive torque as a maximum of said clutch reactive torques multiplied by said line pressure compensation factor; and
determining said minimum clutch torque capacity based upon said critical clutch reactive torque.

### Claim 3 (depends on 1)

The method of claim 1, wherein controlling said hydraulic line pressure applied to said clutch by modulating operation of said hydraulic control system based upon said minimum clutch torque capacity comprises:
determining a minimum required hydraulic line pressure to support clutch operation based upon said minimum clutch torque capacity; and
controlling said hydraulic line pressure applied to said clutch to be no less than said minimum required hydraulic line pressure to support clutch operation.

### Claim 4 (depends on 1)

The method of claim 1, wherein controlling a hydraulic line pressure applied to said clutch by modulating operation of said hydraulic control system comprises changing a hydraulic flow into said hydraulic control system.

### Claim 5 (depends on 4)

The method of claim 4, wherein controlling a hydraulic line pressure applied to said clutch by modulating operation of said hydraulic control system further comprises modulating operation of functions served by said hydraulic control system.

### Claim 6 (depends on 1)

The method of claim 1, wherein modulating operation of said hydraulic control system comprises:
determining a main available flow from a main hydraulic pump;
determining an auxiliary available flow from an auxiliary hydraulic pump;
determining a flow consumption of functions served by said hydraulic control system;
determining an estimated hydraulic line pressure based upon said flow from said main hydraulic pump, said flow from said auxiliary hydraulic pump, and said flow consumption;
determining a desired hydraulic line pressure to fulfill functions served by said hydraulic control system;
comparing said desired hydraulic line pressure to said estimated hydraulic line pressure; and
controlling said main hydraulic pump and said auxiliary hydraulic pump based upon said comparing said desired hydraulic line pressure to said estimated hydraulic line pressure.

### Claim 7

Method for controlling a hydraulic line pressure of a hydraulic control system in 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 via selective application of a plurality of hydraulically-applied torque transfer clutches, said method comprising:
monitoring a current output torque of said transmission;
monitoring a requested output torque command;
adjusting a minimum clutch torque capacity as a feed-forward control comprising:
determining a line pressure compensation factor based upon a greater of one and a ratio of said requested output torque to said current output torque; and
adjusting said minimum clutch torque capacity based upon said line pressure compensation factor; and
controlling said hydraulic line pressure by modulating operation of said hydraulic control system based upon said minimum clutch torque capacity;
wherein said current output torque is generated by providing mechanical power from said electric machine and selectively providing mechanical power from said engine.

### Claim 8 (depends on 7)

The method of claim 7, further comprising:
boosting an available line pressure based upon said requested output torque exceeding a torque capacity.

### Claim 9 (depends on 8)

The method of claim 8, wherein boosting is performed based upon said requested output torque exceeding a current torque capacity.

### Claim 10 (depends on 8)

The method of claim 8, wherein boosting is performed based upon a prediction of said requested output torque exceeding said torque capacity.