Advanced Vehicle Electrical Power Supply System

Abstract

Jaguar Land Rover is focusing on improving fuel economy across the complete vehicle productportfolio. It has invested in new technologies to increase efficiency in all areas including weight,aerodynamics, tyres, friction, powertrain, hybridization and finally electrical systems.This work focuses on the management of electrical energy, including comfort loads, for internalcombustion engine vehicle. The aim of this work is to meet the increasing demand for electrical powerand meet the customers’ expectations in terms of performance whilst minimising their negative impacton fuel economy and emissions.The experimental work with the Low Emissions Vehicle (LEV) demonstrator, initiated, designedand carried out by the author, provided the required understanding of the impact of electrical loads onfuel economy and potential mitigating effects from the use of ultracapacitors, solar panels and highefficiency alternators. The data, collected in environmental dynamometer chamber as well as on UKroads under real world conditions, were used for modelling, calibration and verification.A statistical approach was adopted to derive, from the experimental data, a relationship betweenCO2 emissions and the electrical power resulting from the alternator loading. It forms the fuelconsumption index (FCI) [g.km-1 .A-1].A complete simulation tool for electrical load management was realised in MATLAB®/Simulink™.It includes batteries, alternators, ultracapacitors, solar panels and all electrical features/loads found ona high-end luxury vehicle. The validated, industry standard, model was used to evaluate a novel fuzzylogic electrical energy management control strategy.The proposed controller exploits traditional information such as measured electrical power demand,cabin features usage, driving conditions, battery state of charge and the vehicle’s system electricalstability. In addition it proposes the adoption of the FCI and a customer’s ‘feel factor’, expressed as thecustomer satisfaction index to manage the trade-off between reducing fuel emission and satisfyingcustomer demand.The overall approach was evaluated using extensive simulation studies for a range of realistic testcases representing real world vehicle operation. It was found that the proposed controller cansignificantly reduce CO2 emissions by reducing comfort loads without noticeable effect on thecustomer’s satisfaction. Best savings were obtained by reducing the load during idling and by reducingthe alternator use when the battery can meet the load demand when it operates at a high SoC.

Date of Award	May 2021
Original language	English
Awarding Institution	Coventry University
Sponsors	Jaguar Land Rover
Supervisor	Olivier haas (Supervisor) & Dobrila Petrovic (Supervisor)