Control algorithm for hybrid electric vehicle

• US 8,342,272 B2
• Filed: 03/08/2005
• Issued: 01/01/2013
• Est. Priority Date: 05/03/2001
• Status: Active Grant

• Current Assignee: Ford Motor Company
• Original Assignee: Ford Motor Company
• Inventors: Gee, Thomas Scott
• Primary Examiner(s): Restifo, Jeffrey J
• Application Number:
  US10/906,821
• Publication Number:
  US 20050139400A1
• Time in Patent Office: 2,856 Days
• Field of Search: 180/65.2, 180/65.8, 180/65.3, 180/65.4, 180/65.28, 180/65.285, 180/65.265, 903/943, 123/481, 123/406.55
• US Class Current: 180/65.265
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: F01P 11/16 concerning coolant temperature F01P11/20 takes precedence
• CPC Class Codes: F01P 2025/08 Temperature
• CPC Class Codes: F01P 2050/24 Hybrid vehicles
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A hybrid electric vehicle (HEV) manages engine operation in the event of an engine cooling system malfunction by operating the engine with fewer than the total number of engine cylinders, while extracting power, particularly during transient operation, from not only the engine, but also the vehicle'"'"'s traction motor and battery.

Claims

1. A method for operating a hybrid electric vehicle having a multicylinder internal combustion engine and a traction motor and traction battery, comprising the steps of:

sensing the operating temperature of the internal combustion engine;

sensing the state of charge of the traction battery; and

providing driving power simultaneously from the traction motor and the engine during transient operation, sufficient to approximate the level of power available from the engine operating with all cylinders, while operating the engine at a reduced power level with fewer than the maximum number of cylinders, in the event that the operating temperature of the engine is greater than a predetermined threshold temperature and the battery state of charge is below a calculated charge limit.

2. A method according to claim 1, wherein said calculated charge limit is a function of at least driver demand.

3. A method according to claim 1, wherein said calculated charge limit is a function of at least driver demand and air conditioning usage.