GB2467900A

GB2467900A - Flexible electrical energy storage management in hybrid vehicle

Info

Publication number: GB2467900A
Application number: GB0902203A
Authority: GB
Inventors: Paul Frances Andrews; William Sean Meeson
Original assignee: OAKTEC Ltd
Current assignee: OAKTEC Ltd
Priority date: 2009-02-11
Filing date: 2009-02-11
Publication date: 2010-08-18
Also published as: GB0902203D0

Abstract

A hybrid electric vehicle system with a flexible control architecture that allows the characteristics of its control functions and energy storage systems to be optimised to suit its operating conditions or driving requirements. This system allows vehicles to be optimised for maximum performance and/or maximum fuel efficiency and/or minimum exhaust emissions. The hybrid drive system typically consists of a combustion engine 1, an electric motor/generator 2 and a power transmission device 3. The motor generator 2 converts vehicle motion into electrical energy that is then stored in an energy store 7. On demand the stored electrical energy is used to help provide motion to the vehicle by powering the electric motor 2. This invention allows an engineer or the vehicle driver freedom to choose, by installing values, settings and parameters, how to manage the electrical energy created by the hybrid system, at what rate to capture it and re-use it and by what means to store it within this flexible control architecture.

Description

INTELLECTUAL

. .... PROPERTY OFFICE Application No. GB0902203.9 RTM Date:31 March 2009 The following terms are registered trademarks and should be read as such wherever they occur in this document: Honda Insight Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk

Description

A vehicle hybrid system consisting of (see schematics A,B &C) * A Combustion Engine 1, one or more Electric Motor/Generators (EMG) 2, and a Power Transmission System 3 * An Engine Management System (EMS) 4 that controls the combustion engine * An Electrical Energy Store (EES) 7 consisting of batteries and/or capacitors and or other storage devices * An Electrical Energy Management Module (EEMM) 8 which manages the temperature and state of charge of the energy store, and its other inputs and outputs * A Motor/Generator Control Module (MGCM) 9 which communicates with the EEMM 8 and manages energy flows between it and the motor generator * A Motor/Generator Drive Module (MGDM) 5 which is controlled by the MGCM 9 and switches the EMG 2 between motor and generator functions * A DC/DC Converter 6 if an auxiliary lower voltage electrical system is needed The invention described here can be used as a replacement control system to modify and give flexibility to an existing hybrid system or to provide a full hybrid control product for a stand-alone system. It is a package of hardware and software, giving the engineers installing or programming the system complete flexibility to set its parameters and tune its operating characteristics and strategies by mapping software embedded in the system. It also allows flexibility in the choice of electrical energy storage solution for any particular application within the same basic control hardware package.

The area within the shaded box in Schematic A that includes the EEMM 8 and the MGCM 9 is the part of the hybrid system that is unique and critical to the successful implementation of this invention.

The EEMM 8 is responsible for the management of the EES 7 and monitors functions such as rate of charge and discharge, maximum and minimum charge levels, state of charge, temperatures, energy store cooling management, individual cell condition, system safety and any other functions that may be used in an energy storage device. The EEMM 8 creates the interface between the selected energy storage solution and the MGCM 9. Values and settings can be programmed into the EEMM 8 to set its operating parameters and operational characteristics.

The MGCM 9 uses information from the EEMM 8 and uses a microprocessor that is responsible for decisions relating to electrical energy flows for charging the EES 7 by regeneration or other charging, powering the EMG 2 for drive assist, functions such as stop/start if fitted, and any other functions that may be built into a hybrid system. It can process information from the EMS 4 to determine drive and regeneration requirements, the Brake System 13 for regeneration requirements and the EEMM 8 for energy storage information. The MGCM 9 can provide a system diagnostic function and information to cockpit instrumentation.

Values, settings and maps can be programmed into the software of the MGCM 9 to set its operating parameters and operational characteristics.

The MGCM 9 computes information received and provides instruction to the MGDM 5 for control of the energy flows to and from the EMG 2. The MGDM 5 is the device that switches the flow of electrical energy between power, neutral and regeneration. it can also include a electrical power inverter and a high to low voltage DC/DC Converter 6 if such a system is needed. 2.

The EEMM 8 and the MGCM 9, shown separate in this example, could be embodied in the same single component still fulfilling the functions as described above, or that an embodiment using additional components such as one or more controllers to facilitate programming could be interfaced into the system.

An embodiment of the system will accept signals from a manually operated switching device, Driver Manual Controller 12, that will over-ride the values set in the MGCM 9 and give the driver control over the levels, rates and timing of the regeneration and assist functions, within the working parameters of the system.

Another embodiment enables the MGCM 9 or other parts of the system to be tuned by the vehicle driver through a mapping device, Driver Settings 11, fitted in the cockpit.

A further embodiment of the system will incorporate the function to accept additional sources of electrical energy into the EES 7. This is shown as second generator 14 in schematic B. A further embodiment of the system will incorporate the function to power more than one electrical system either to drive the vehicle and/or vehicle ancillary parts. This is shown as Additional Power Feedsl5 in Schematic C. A further embodiment will incorporate an energy store of sufficient capacity to enable a mains plug in' charging facility to expand the available use of the electric drive within of the hybrid system. This is shown as Plug In Charging Facility 16 in Schematic C. Uses A system of this type has a variety of possible uses. Acceptance of differing energy stores allows the option to specify the same type of hybrid vehicle with an energy storage solution optimised to meet specific requirements in terms of cost, energy density, performance, weight or safety.

Examples for use range from a simplified application for a low cost hybrid/electric commuting vehicle to a sophisticated multifunctional system in a racing or rally car.

A hybrid delivery vehicle using this system could have a optimised energy store to take account of payload, journey distance, frequency of acceleration and braking events, and an ideal performance map to optimise energy recovery and power delivery to maximise fuel economy and minimise emissions.

Introduction

Automotive hybrid systems combining combustion engines with electric motor/ generators are now a well-known and accepted technology. These systems, typified by the Honda IMA and Toyota HSD hybrids, have the potential to increase the efficiency of a vehicle by capturing kinetic energy that a traditional vehicle would waste and converting it to electrical energy and storing it, typically, in a dedicated battery. The hybrid system then releases this energy when demanded to an electric motor that assists with the powering of the vehicle.

It is often not fully appreciated that the same system can be used to increase the road performance of the vehicle as the regeneration of kinetic to electrical energy adds to the braking system of the vehicle whilst the electric motor provides a net increase in power to provide acceleration. Having the ability to optimise the characteristics of the electrical system in a hybrid vehicle gives the opportunity to exploit both the efficiency and performance potential inherent in the system.

The invention described here provides a solution for a vehicle requiring higher levels of performance and/or efficiency than is the norm for a current mass-market system. It allows the potential, within the limitations of the hardware employed, to tune the system to capture much more of the vehicle's kinetic energy than a normal manufacturer's production system and therefore have more stored energy to aid the efficiency and/or performance of the vehicle. It also allows the vehicle user the scope to set up the characteristics of the vehicle to achieve optimum performance and/or efficiency to suit its driving cycle or operating terrain. It provides the flexibility to employ an energy storage solution optimised for purpose in terms of type, cost, performance and storage capacity.

This invention would have a particular use in sporting cars, specialist and niche market vehicles, vehicles that need to achieve very high fuel efficiency and/or low emissions, racing vehicles and for the enthusiast driver who demands a higher level of control over the vehicle.

Prior Art

A vehicle-specific device, that provides some of the solutions covered by this patent, was invented by Mike Dabrowski as an add-on controller for the first generation Honda Insight Hybrid, with the aim of improving the fuel efficiency potential of that car. This device, called MIMA, allows the vehicle owner to reset a limited number of control parameters of the standard Insight hybrid system, but does not have any inherent flexibility for the use of non-standard energy storage devices, and is not applicable to vehicles other than the Honda Insight.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVEPROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS: 1. A vehicle hybrid power system including a combustion engine, an electric motor/generator, a transmission device and an electrical energy store, governed by a microprocessor based control architecture that provides the facility to alter the settings, parameters and working control strategies of the hybrid system to allow the vehicle performance and/or efficiency to be changed or optimised.
2. A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to accept and work with different devices to store electrical energy to suit differing vehicle requirements.
3. A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to be adapted to work with combinations of different electrical energy storage devices.
4. A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to be adapted to accept and work with different chemistries of battery in its electrical store.
5. A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to be adapted to operate at different hybrid system voltages.
6. A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to be adapted to work with different capacities of electrical energy storage.
7. A vehicle hybrid system as defined in claim I including the provision of a facility to enable the electrical energy store to be adapted to accept electrical energy input from more than one source.
8. A vehicle hybrid system as defined in claim 1 including the provision of a facility to enable it to be adapted to provide electrical power to drive more than one recipient component.
9. A vehicle hybrid system as defined in claim 1 including the provision of a facility to enable it to be adapted to work with a cockpit mounted driver activated manual control mechanism that can over-ride all or some of the settings programmed into the system.
1O.A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to be adapted to work with a driver activated mapping device that allows some or all of the system settings to be programmed from the control area or cockpit of the vehicle.
11. A vehicle hybrid system as defined in claim I including the provision of a facility to enable it to accept electrical charge from an external source such as a mains supply.
12.A vehicle hybrid system as defined in Claim I and including any or all of those features described in Claims 2 to 11.