Active accessory drive control system

• Main Authors: Wassim Koubaa, Ian Robinson, Dave Perkins, Nick Dashwood Crisp, Nicole Barrett
• Format: Patent
• Language: English
• Published: 19.02.2020
• Subjects: BLASTING; COMBUSTION ENGINES; COMBUSTION ENGINES IN GENERAL; CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE ORDIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; INTERNAL-COMBUSTION PISTON ENGINES; LIGHTING; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TOTHE CONTROL OF A PARTICULAR SUB-UNIT; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDEDFOR; STARTING OF COMBUSTION ENGINES; THERMAL INSULATION IN GENERAL; TRANSPORTING; VEHICLES IN GENERAL; WEAPONS

A method of operating a front end accessory drive system for a motor vehicle, wherein the accessory drive system comprises one or more accessory components pulleys, e.g. air conditioner pulley 106, a motor generator pulley 102, a drive pulley 104, first and second idler pulleys 108, 110 and a flexible drive element, such as drive belt 112, configured to transmit a torque load between the one or more accessory components pulleys and the motor generator pulley. The method comprises determining a condition of the belt, determining a maximum permissible belt torque threshold, based on the determined condition of the belt. The method includes detecting an increase in torque demand on the belt, e.g. during a recuperation event, and determining when the torque demand on the belt will exceed the belt torque threshold. The method involves reducing the torque demand of one or more accessory components and/or a motor generator, so that the belt torque threshold is not exceeded and the belt will not experience parasitic losses such as belt slip and/or stretch etc.