GB2531606A

GB2531606A - Variable speed forced induction with energy recovery and drive control

Info

Publication number: GB2531606A
Application number: GB1418995.5A
Authority: GB
Inventors: Marsh Peter; Ninan-Cherian Ashish
Original assignee: TURBO DYNAMICS Ltd
Current assignee: TURBO DYNAMICS Ltd
Priority date: 2014-10-24
Filing date: 2014-10-24
Publication date: 2016-04-27
Also published as: WO2016063266A2; GB201418995D0; WO2016063266A3

Abstract

A forced induction system 1A for an engine 101 comprising a compressor 2 configured to supply air to an inlet of an engine; and a fluid control system connected to the compressor. The fluid control system comprises a fluid motor 4 configured to drive the compressor, and a flow control valve 54. Fluid flow to the fluid motor is controllable by the flow control valve so that the speed of the fluid motor, while driving the compressor in use, can be controlled by the operation of the flow control valve. The forced induction system may be utilised as a turbocharger system in which the turbine 3 and compressor 2 are split into two separate units with their shaft speeds capable of being independently operated at varying speeds. The arrangement makes it possible, to keep the turbine at the exhaust side and compressor at the inlet side thus in the case an internal combustion engine with turbochargers eliminating the physical constraint of the turbocharger setup, piping losses, thermal interactions, or for better engine packaging.

Description

VARIABLE SPEED FORCED INDUCTION WITH ENERGY RECOVERY AND DRIVE

CONTROL

FIELD OF THE INVENTION

Lou The present invention relates to a forced induction system, in particular to supercharging and/or turbocharging systems for an engine and/or motor.

[02] The invention also relates to a hydraulic energy recovery and transmission system for an engine and/or motor.

BACKGROUND OF THE INVENTION

[03] In current turbocharging systems for an internal combustion engine, the turbine and the compressor units are interconnected in close proximity to each other by a rigid common shaft which limits the possibilities avail able for engine packaging and physically constrains the positioning of the compressor and turbine units with respect to each other. This results in complex piping, leading to piping losses and thermal interactions between the turbine and compressor units due to their close proximity.

[04] In addition, the compressor and turbine units cannot be operated at different shaft speeds as they are interconnected by the common rigid shaft.

[05J There is also a considerable amount of energy that is wasted by the operation of waste gates and blow off valves in order to regulate the air flow, operational speeds and pressures within the turbine and compressor units as required for the optimal performance of the engine. Known turbocharging systems have limits in the levels of boost pressure that can be produced with respect to engine speeds which limits linearity in performance, and creates turbo lag.

[6] Also considerable wastage in energy occurs while braking is carried out in a vehicle, this has led to the need for developing brake energy recovery systems. The current brake energy recovery systems either use electrical or mechanical means which limit the amount of energy that can he effectively recovered and reused. This is because the electrical systems require a large battery which needs to he replaced at regular intervals; in addition there is also the wastage of energy which occurs while the energy is being converted from other forms of energy into electrical energy so that it can be stored in the batteries. While mechanical systems add considerable weight as well as limits the possibilities for the ways in which the energy can he stored, transferred and reused.

[7] It would therefore be beneficial to provide a system which can address one or more of the problems identified above.

SUMMARY OF THE INVENTION

[08] According to a first aspect, there is provided a forced induction system for an engine comprising: a compressor configured to supply air to an inlet of an engine; and a fluid control system operatively connected to the compressor; wherein the fluid control system comprises a first fluid motor configured to drive the compressor, and a flow control valve; and wherein fluid flow to the first fluid motor is controllable by the flow control valve so that the speed of the first fluid motor, while driving the compressor in use, can be controlled by the operation of the flow control valve.

1091 01 exemplary embodiments of a first configuration of the forced induction system, the fluid control system further comprises a fluid pump configured to he driven by the engine.

1101 The forced induction system according to the first configuration may further comprise a magnetic clutch system configured to couple the fluid pump to the engine.

[11] The fluid control system may incorporate a hydraulic power steering pump in addition to or nstead of the fluid pump.

[12] Such a forced induction system may be utilized as a hydraulic supercharger system for an engine.

[13] The forced induction system may further comprise an accumulator configured to store energy as fluid pressure, the accumulator comprising a first input port in fluid communication with an output port of the fluid pump, and a first output port in fluid communication with an input port of the first fluid motor.

[14] The forced induction system may also further comprise a fluid reservoir, the fluid reservoir comprising a first output port in fluid communication with an input port of the fluid pump, and a first input port in fluid communication with the output port of the first fluid motor.

[151 In exemplary embodiments, the forced induction system may further comprise a speed varying mechanism positioned between the compressor and a mating component.

[16] In the forced induction system according to the first configuration, the compressor may be thermally isolated from any surrounding heat source.

[17] In exemplary embodiments of a second configuration of the forced induction system, the system further comprises a turbine. The turbine is configured to be operated by exhaust gases of the engine.

1181 The fluid control system may further comprise a first fluid pump configured to he driven by the turbine.

[19]Embodiments of the forced induction system further comprising a turbine may he utilized as a hydraulic turbocharger system for an engine.

[20] In exemplary embodiments, the fluid control system may further comprise a second fluid pump configured to he driven by the engine.

1211 In exemplary embodiments, the forced induction system may further comprise a speed varying mechanism positioned between the turbine and the compressor; between the turbine and a mating component; or between the compressor and a mating component. The speed variation mechanism may comprise an electric clutch, a gear box, a hyperbolic gear drive, a torque convertor, a fluid coupling, or a free wheel mechanism, etc. [22] In known turhocharging systems, the compressor and the turbine shafts are coupled together by a rigid shaft making it impossible for the units to he optimised individually. The system in accordance with the invention solves these issues by providing a variable speed turhocharging system in which the compressor and turbine shafts can be operated at varying speeds with respect to each other thus allowing the units to be optimised individually to run at varying rpms.

[23] In exemplary embodiments, the forced induction system further comprises an accumulator configured to store energy as fluid pressure, the accumulator comprises a first input port in fluid communication with an output port of the first fluid pump, a second input port in fluid communication with an output port of the second fluid pump, and a first output port in fluid communication with an input port of the first fluid motor.

[24] The forced induction system may further comprise a fluid reservoir, the fluid reservoir comprising a first output port in fluid communication with an input port of the first fluid pump, a second output port in fluid communication with an input port of the second fluid pump; and a first input port in fluid communication with the output port of the first fluid motor.

1251 In exemplary embodiments, the turbine and the compressor are thermally isolated from one another since they can he positioned without physical constraints as they are connected by flexible hydraulic lines.

1261 A forced induction system in accordance with the invention may he utilised to provide additional functions such as: minimising blow off and waste gate valve operations; driving the compressor at low speeds; reducing operational speeds of the turbine and compressor and improving the linear performance; dynamically variable cylinder pressure; independently variable cylinder air flow control variable engine braking; and thermal cycling and emission control.

1271 The forced induction system in accordance with the invention also bridges the gap between a turbocharger and supercharger by adding the benefits of a supercharger to the turbocharging system thus eliminating turbo lag.

The invention also has the additional advantage of providing a system which can be managed with better thermal efficiency, better engine packing potential while reducing the energy wasted in blow off and waste gate valve operations. The above mentioned functions would make a vehicle more energy efficient and less polluting while providing a highly controllable air flow management system for the engine.

[28] The forced induction system according to the first aspect may further comprising one or more sensors, and an electronic control unit configured to control one or more parameters and/or components of the forced induction system.

[29] One or more solenoid valves and/or solenoid valve actuators may be incorporated in the forced induction system for facilitating the electronic control unit in controlling the one or more parameters and/or components of the forced induction system.

[30J According to a second aspect, there is provided an energy recovery system comprising a fluid accumulator; a fluid reservoir; a fluid motor; a fluid pump and a fluid control system comprising one or more flow control valves. The fluid accumulator comprises a first input port configured to he in fluid communication with an output port of the fluid pump and the fluid reservoir comprises a first output port configured to be in fluid communication with an input port of the fluid pump. The fluid reservoir comprises a first input port configured to he in fluid communication with an output port of the fluid motor and the fluid accumulator comprises a first output port configured to he in fluid communication with an input port of the fluid motor.

[31] The energy recovery system may further comprise a fluid device, the fluid device comprising a first port in fluid communication with a two-way port of the fluid accumulator and a second port in fluid communication with a two-way port of the fluid reservoir.

[32] In exemplary embodiments, the fluid device may comprise either a fluid pump or a fluid motor or a combined fluid motor / pump unit. When the combined unit is employed a separate fluid pump may be omitted as the device can he made to carry out the stated function. The fluid device functions as a pump/motor based on the opening and closing of the various fluid flow direction control valves controllable by an ECU.

1331 In exemplary embodiments, the energy recovery system may further comprise a fluid coupling/a torque convertor/a freewheel mechanism/a freewheeling clutch/an overrunning clutch attachable to a drive shaft of a vehicle. The arrangement if necessary can be located before the gear box so that when a mechanical single directional freewheel or similar device is employed it would always he operated in a single direction without having to deal with additional directional changes as such when reverse gear is selected. The fluid coupling/torque convertor is configured to be operated so as to decouple the engine of the vehicle from the drive shaft as and when required by the operation of valves that allow the fluid coupling/torque convertor to be filled with fluid from the accumulator and/or drain fluid to the reservoir as required so that the coupling starts to slip when the level of fluid is below a critical level.

[34] The energy recovery system in accordance with the second aspect can he used to carry out various beneficial functions such as: energy recovery and combined braking; transmission of power to the wheels; multiple wheel drive arrangement; traction control; cruise control; traffic crawling; automatic function in manual transmission; hill ascent and descent; engine decoupling: differential; and independent suspension and steering.

[35] According to a third aspect, there is provided a combined forced induction and energy recovery system for a vehicle comprising a forced induction system in accordance with the first aspect; and an energy recovery system in accordance with the second aspect.

1361 According to a fourth aspect, there is provided a turbocharger system for an engine of a vehicle comprising: a turbine configured to he operated by exhaust gases of an engine; a compressor configured to supply compressed air to an inlet of the engine; and a speed varying mechanism positioned between the turbine and the compressor or the turbine and a mating component and/or the compressor and a mating component.

[37] The separation of the functional units enables the compressor and turbine units to be located, operated and optimised individually with independent shaft speeds. The implementation of the technology would give the ability to manage the engine's operating parameters more effectively and efficiently; and the vehicle's motion with improved precision and performance.

[38] In exemplary embodiments, the speed variation mechanism may comprise an electric clutch, a gear box, a hyperbolic gear drive, a torque convertor, a fluid coupling, a free wheel mechanism, etc. [39] In exemplary embodiments, the turbine and compressor of the turbocharger system may be thermally isolated from each other, and the turbocharger system comprises a flexible cable arrangement coupling the turbine to the compressor. The flexible cable arrangement may comprise an inner rotating cable portion and an outer fixed cable portion.

1401 In exemplary embodiments, the turbine and compressor of the turbocharger system are thermally isolated from each other on a common shaft and said shaft may be mounted on one or more bearings configured to balance the shaft. The shaft may incorporate a universal joint or bevel gear so as to provide a certain degree of variation in motion angle.

[41] According to a fifth aspect, there is provided a turbocharger system for an engine of a vehicle comprising: a turbine configured to he operated by exhaust gases of an engine; a compressor configured to supply compressed air to an inlet of the engine; and a flexible cable arrangement coupling the turbine to the compressor, the flexible cable arrangement comprising an inner rotating cable portion and an outer fixed cable portion, wherein the turbine and compressor are thermally isolated from each other.

[42J According to a sixth aspect, there is provided a turbocharger system for an engine of a vehicle comprising: a turbine configured to he operated by exhaust gases of an engine; and a compressor configured to supply compressed air to an inlet of the engine; wherein the turbine and compressor of the turbocharger system are thermally isolated from each other on a common shaft and said shaft may he mounted on one or more bearings configured to balance the shaft.

[43] The invention in accordance with the fourth, fifth or sixth aspect provides ways in which existing turbochargers can be altered by the introduction of certain components between the shafts of the turbine and the compressor such as a speed varying mechanism. This provides a cost effective alternative to the full hydraulic system in accordance with the first aspect.

[44] According to a seventh aspect, there is provided a vehicle comprising an energy recovery system according to the second aspect; one or more sensors located within the vehicle; and an electronic control unit (ECU) configured to control one or more parameters and/or components of the vehicle and/or energy recovery system. The ECU may receive additional inputs from manually operated switches so as to carry out the desired functions as needed.

1451 The vehicle may comprise one or more solenoid valves and/or solenoid valve actuators for facilitating the electronic control unit in controlling the one or more parameters and/or components of the vehicle and/or energy recovery system.

[46] In exemplary embodiments, the vehicle further comprises a fluid device associated with each wheel of the vehicle, each fluid device comprising an input port in fluid communication with a two-way port of the fluid accumulator and an output port in fluid communication with a two-way port of the fluid reservoir.

1471 The vehicle may further comprise a fluid coupling before the transmission or on a draft shaft driven by an engine of the vehicle, the fluid coupling configured to selectively couple or decouple a section of the draft shaft from the engine.

[48] According to an eight aspect, there is provided a method of controlling one or more parameters and/or components of a vehicle comprising the steps of: -providing in a vehicle, a forced induction system according the first aspect or a combined forced induction and energy recovery system according to the second aspect; -positioning the one or more sensors within the vehicle and configuring the one or more sensors to measure data in relation to one or more components of the vehicle; -configuring the electronic control unit to collect and process data in relation to the one or more components of the vehicle based on data measured by the one or more sensors; -configuring the electronic control unit to control or adjust one or more parameters and/or components of the vehicle and/or forced induction system in response to the collected and processed data.

[49] The electronic control unit may he configured to control or adjust one or more parameters and/or components of the vehicle and/or forced induction system in response to the collected and processed data in order to carry one or more of the following functions: minimising blow off and waste gate valve operations; driving the compressor at low speeds; reducing operational speeds of the turbine and compressor and improving the linear performance; dynamically variable cylinder pressure; independently variable cylinder air flow control; variable engine braking; and thermal cycling and emission control.

1501 The system may employ one or more pressure relief valves and flow check valves so as to ensure the fluid flow is as desired and in a controlled manner. There are other applications which would benefit from the use of having a variable shaft speed between the turbine and the mating component, for example -steam power plants where there are turbines driving electric generators in which the ability to provide speed variations as per load requirements would he beneficial; jet engines; wind turbines where the wind turbine is connected to the generator can make use of a system which not only provides variable speed but also the ability to load the turbine hydraulically which would prevent over speeding of the turbine which is a major cause of catastrophic failures of wind turbines. Currently this is being done with the help of mechanical brake arrangements but the energy recovery system in accordance with the invention can he adapted to meet such needs, and to also assist the generator so that it can be driven from the stored hydraulic energy from the accumulator so that a constant speed of operation is possible taking out the fluctuations in the system that are otherwise present. Other examples include propeller shafts in water vessels where there could be an added benefit of water tight sealing as the external propeller may he driven by a hydraulic motor attached to hydraulic lines with the driving elements located within the vessel; making it more effective to have a water tight seal rather than trying to make the rotating shafts water tight.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will he described with reference to the accompanying drawings, in which: [51] Figure 1 is a schematic view of a vehicle comprising a hydraulic variable turbochareing engine system and a hydraulic energy recovery system [52] Figure 2 is a schematic view of the turbocharger forming part of the turbocharging engine system [53] Figures 2A to 2D are schematic views of different embodiments of the speed varying mechanisms between the turbine and compressor shafts that can be used on existing turbochargers so that a variable speed turbocharger can be implemented; and 1.54] Figures 3A, 3A1 and 3B depict different mechanical coupling arrangements for coupling the turbine and compressor with each other.

DETAILED DESCRIPTION OF EMBODIMENTS

[551 The preceding discussion on the background of the invention is intended only to facilitate an understanding of the present invention. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge as on the priority date of the application.

[56] Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of the words, for example "comprising" and "comprises", mean "including but not limited to", and is not intended to (and does not) exclude other components, integers or steps.

1571 Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to he understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[58] Features, integers or characteristics, and compounds described in conjunction with a particular aspect, embodiment or example of the invention are to he understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.

1591 The use of the term 'turhocharging system is not intended to limit the possibility for the forced induction system to be simplified, that is it may be used as a supercharger, or the fact that the forced induction system may be adapted to be used in other industries such as the power generation industry where the turbine's working fluid is steam and is not generally called a turbocharger. A 'turbocharging system' in the present context relates to system including a turbine for recovering energy from a fluid and a compressor driven by the recovered energy and configured to supply compressed fluid to an inlet of an engine.

[60] The hydraulic system in accordance with the invention is described herein to address the issues associated with an internal combustion engine hence the use of the words "turhocharging", "supercharging". The usage of these words in no way limits the field of invention preventing it from being used in other fields as described below.

[61] Referring to figure 1, an embodiment of a hydraulic system 1, in the form of a combined forced induction and energy recovery system, in accordance with the invention is shown. The hydraulic system 1 comprises the following components -an electronic control unit (ECU) 111 and two subsystems, a variable speed hydraulic forced induction system lA and a hydraulic energy recovery system 1B. The components are described in more detail later on.

[62] The hydraulic fluid used within the hydraulic system I can he either oil, water, a synthetic based fluid etc. as long as the fluid is capable of power transmission and the invention is not limited to any particular fluid type. In the embodiment shown, the subsystems lA and I B share common elements such as a fluid reservoir 17, a fluid accumulator 18, and a fluid pump 12 which is configured to be driven by the engine 101 of a vehicle 100. It is possible to eliminate the fluid pump 12 and instead use a hydraulic power steering pump or use the power steering pump in conjunction with the fluid pump 12 of the hydraulic system 1 in accordance with the invention.

1631.11e vehicle 100 comprises a pair of front wheels 104, 105 coupled to each other by a front wheel axle or steering rack (not shown) (or may be implemented as described below when all wheel drive is required); and a pair of rear wheels 108, 109 coupled to each other by a rear wheel axle 116. The rear wheel axle 116 is coupled to a differential 117 which is driven by a drive shaft 148 operated by a transmission system 102 attached to the engine 101. In the embodiment shown, the engine is in the form of a four-stroke four cylinder engine with four individual inlet runners 121, 122, 123 and 124 leading to a common inlet manifold 106, and an exhaust manifold 107. The description is not limited to the type of engine described above and it would be understood that the selection of the engine for the description is for explanatory purposes only.

Electronic control unit (ECU) and associated components [64] The electronic control unit (ECU) I 1 1 is positioned within the vehicle 100 and is configured to control a number of parameters and/or components of the vehicle, as well as to collect and process data in relation to the various parameters of the vehicle 100 by means of sensors located in the vehicle 100. For example information relating to: -the position of the steering wheel 144 is obtained via a steering wheel position sensor 145; - the position of the throttle 146 is obtained via a throttle position sensor 141; - the position of the brake pedal 115 is obtained via a brake pedal position sensor 114; - the position of the accelerator pedal 134 is obtained via an accelerator pedal position sensor 133; - the position of the gears of the vehicle 100 is obtained via a gear position sensor 138; -the wheel speed of the vehicle 100 is obtained via wheel speed sensors 150, 151, 152, and 153 corresponding to the front left, front right, rear left and rear right wheels respectively; - the exhaust temperature is obtained via an exhaust temperature sensor 147; - the inlet temperature is obtained via an inlet temperature sensor 143: - the engine speed is obtained via an engine speed sensor 129; - the boost pressure in the inlet manifold is obtained via a boost pressure sensor 142; - the speed of a fluid device 216 via a speed sensor 244.

[65] The ECU ill also controls a number of solenoid valves and solenoid valve actuators located within the vehicle, for example fluid flow solenoid valves 10, 236, 237, 251, 252, 54, 55, 56; a blow off solenoid valve actuator 46; a waste gate solenoid valve actuator 47; and fluid flow displacement solenoid valves 8, 9, 11, 235, which are positioned within the hydraulic system 1. The solenoid valves and solenoid valve actuators facilitate the ECU III in controlling the required parameters and/or components of the hydraulic system I based on the input from the various sensors in a manner as detailed below so that the engine's 101 operations and the vehicle motion are more effectively controllable.

16611'11e ECU 111 also controls butterfly valves TV 1, l'V2, TV3 and '1V4 located in the inlet runners 121, 122, 123 and 124 respectively of the inlet manifold 106 so that other operations/functions as explained in detail below are possible.

The variable speed forced induction system lA [67] The variable speed forced induction system IA comprises a turbine unit 3 (herein after referred to as a "turbine") and a compressor unit 2 (herein after referred to as a "compressor") which are arranged as separate units. The forced induction system lA of Figure 1 is thus arranged as a turbocharging system, although it would be understood that the forced induction system in accordance with the invention may be arranged in numerous different configurations.

[68] The forced induction system lA also comprises a fluid control system operatively connected to the compressor 2 and the turbine 3. The fluid control system comprises a fluid pump 5 configured to be driven by the turbine 3 and a fluid motor 4 configured to drive the compressor 2.

[69] The turbine 3 is driven by the gases from the exhaust manifold 107 produced by the engine 101. The shaft of the turbine 3 is mated to a shaft of the fluid pump 5. A speed variation mechanism 7 may be positioned between the shafts of the turbine 3 and the fluid pump 5 as shown in Figure 1 if required. The speed varying mechanism 7, for example, may be a gear arrangement, a hyperbolic gear drive, an electric clutch or any other suitable mechanism which provides the ability to operate the two shafts at different speeds with respect to each other.

1701 the compressor 2 outlet is connected to the inlet manifold 106 of the engine 101 supplying it with compressed air as required. [he shaft of the compressor 2 is connected to a shaft of the fluid motor 4. A speed varying mechanism 6 may be positioned between the shafts of the compressor 2 and the fluid motor 4 as shown in Figure 1 if required. This allows a low motor speed to be converted into a higher speed capable of driving a centrifugal compressor should such a compressor he used. The system does not limit itself to any particular type of compressor.

[71_1.1:he ECU III is configured to control, collect and process data in relation to the speeds of the compressor; turbine, fluid motor 4 and fluid pump 5 by means of sensors located in the vehicle. For example, information relating to: - the speed of the compressor is obtained via a speed sensor 28; - the speed of the turbine is obtained via a speed sensor 26; - the speed of the fluid motor 4 is obtained via a speed sensor 27; - the speed of the fluid pump S is obtained via a speed sensor 5; and -the speed of the drive shaft 148 by a speed sensor 245.

1721 As previously mentioned, the forced induction system lA may comprises a shared fluid accumulator 18 and fluid reservoir 17 with the energy recovery system 1B. The fluid accumulator 18 is configured to store energy as fluid pressure. In the embodiment shown, the accumulator 18 comprises a first output port 18B1 is-in fluid communication with an input port 4A of the fluid motor 4, and a first input port 18A1 in fluid communication with a flow control valve 56 which is connected to an output port 12B of fluid pump 12. The fluid reservoir 17 comprises a first output port 17B1 in fluid communication with an input port 12A of the fluid pump 12. The accumulator 18 further comprises a second input port 18A11 in fluid communication with an output port 5B of the fluid pump 5 between which there is the flow control valve 55. The fluid reservoir 17 further comprises a second output port 17B11 in fluid communication with an input port 5A of the fluid pump 5.

[73] The forced induction system IA further comprises a flow control valve 10 which controls the pressurised fluid flow from the first output port 18B1 of the accumulator 18 to the input port 4A of the fluid motor 4 driving it. Fluid exits the fluid motor 4 via the output port 4B passing through another flow control valve 54 then into the reservoir 17 via the first input port 17A1. The speed of the fluid motor 4 can be controlled by the ECU 111 by regulating the degree to which the flow control valve 10 opens or closes. The air flow into the engine 101 is therefore controllable by the ECU 111 as the increase or decrease in the fluid motor's 4 operational speed leads to an increase or decrease in the air flow output from the compressor 2 because the air flow output is related to the speed of operation of the compressor wheel which is mated to the fluid motor 4 via the shaft of the compressor 2.

[74J The degree to which the speed of the compressor 2 or turbine 3 is operated can he controlled by the ECU 111 by regulating a flow displacement valve 8 of the fluid motor 4 attached to the compressor's 2 shaft in conjunction with the flow control valve 10 or a flow displacement valve 9 of the fluid pump 5 attached to the turbine's 3 shaft in conjunction with the flow control valve 55 based on the inputs from speed sensors 25, 26, 27, 28 and 129.

175J A magnetic clutch system 13 which is configured to he actuated by the ECU III is positioned within the vehicle 100. The magnetic clutch system 13 is arranged such that it can he actuated as required by the ECU 111 in order to couple the fluid pump 12 to the engine 101. The fluid pump 12 while in operation creates a braking force by placing an additional load on the engine 101 which in turn brings down the engine speed. As a result, the speed of the vehicle 100 is reduced as the wheels 108, 109 are indirectly coupled to the engine 101. If required the fluid pump 12 can be operated to provide pressurised fluid when additional input fluid flow is required by the fluid motor 4 or a fluid device 216. The operation of the fluid device 216 is described in further detail later on.

[76] The fluid pump 5 and the fluid motor 4 are interconnected by hydraulic fluid lines. The hydraulic fluid lines are flexible giving the possibility for the turbine 3 and compressor 2 to be orientated in any required location. This allows the turbine 3 and compressor 2 to he thermally isolated from each other, thus reducing the likelihood of heat interactions between them. This improves the efficiency of the compressor 2 by a substantial margin, reducing the air piping losses as well as making it possible to have better engine packaging and positional orientations which permits better weight optimisation. This is beneficial in applications such as racing where the centre of gravity is required to he as low as possible, and the forced induction system in accordance with the invention would allow the turbine 3 and compressor 2 to he relocated as required which is currently not possible due to the use of a fixed shaft between the turbine and compressor in current turbochargers systems.

1771 In exemplary arrangements, if required, the compressor 2 can he finned and kept at the front of the engine 101 or where unrestricted air supply is available. This assists in reducing the temperature of the compressor 2 by disposing the heat generated from the compression of air. This is possible due to the fact that the turbine 3 and compressor 2 are free to he located anywhere within the engine compartment of the vehicle 100 with no physical constraint with each other.

1781 As previously mentioned, the turbine 3 is configured to he driven by exhaust gases from the engine, and the location of the turbine 3 may he behind the engine 101 or in a location where it would have reduced heat dispersion or positioned to suit requirements. This would help to maintain optimal exhaust temperatures and assist a catalytic convertor (if present) to he more effectively optimised. This could have significant advantages in bringing the exhaust emissions down.

1791 The turbine's 3 shaft speed and the compressor's 2 shaft speed are capable of being independently operated at varying speeds such that each unit can be individually optimised effectively.

1801 The fluid pump 5, fluid pump 12 and fluid motor 4 may he may he in any form suitable to carry out the required functions outlined above. For example, they may be of the variable displacement type, fixed type etc. The system may employ one or more pressure relief valves and flow check valves so as to ensure the fluid flow is as desired and in a controlled manner.

[81] The hydraulic forced induction system I A can make the engine 101 effectively respond better and in a controlled manner thereby reducing CO] emissions. This also can increase the power output which can help to downsize the engine displacement so that a smaller engine can now deliver the same performance in the process, whilst also offering a weight reduction advantage.

[82] While the forced induction system 1 A has been described in relation to a vehicle, it may he utilised in other fields such as for example in a wind turbine, power plant etc. In such applications, the working/operational fluid driving the turbine 3 may he atmospheric air, steam, water or other suitable fluid medium. The motor driving the compressor may be used to drive an electric generator or other mating component at the required speed.

The energy recovery system 1B [83] As previously mentioned, the energy recovery system 1B comprises a shared fluid accumulator 18 and fluid reservoir 17 with the forced induction system IA. The fluid accumulator 18 is configured to store energy as fluid pressure.

[84] The energy recovery system 1B further comprises a fluid device 216 which is configured to be coupled to the rear drive shaft 148 of the vehicle 100. The fluid device 216 may he in the form of a single combined reversible fluid motor and fluid pump unit. The current available options for such a device which can function effectively with high efficiency as a pump and motor may not be easily/cheaply available, and in such a case the motor and pump functions of the fluid device 216 can be implemented by separate units coupled to the drive shaft 148. It also is possible to omit either the pump or motor function depending on the additional functions needed, as described in more detail below these may he omitted when a low cost implementation of the energy recovery system 1B is required.

1851 At least one flow direction valve is provided which is configured to control the fluid flow direction in and out of the fluid device 216. In the embodiment shown, the energy recovery system 1B comprises two two-way flow directional valves 230 and 231 and two fluid flow control valves 237 and 236, all capable of being controlled by the ECU 111. Each of the two-way flow directional valves 230, 231 comprises three pipes 230A, 230B, 230C and 231A, 231B, 231C respectively connected thereto.

1861 'File fluid device 216 comprises a first two-way port 216ABI in fluid communication with the two-way flow direction-valve 230. The two-way flow direction valve 230 is connected to a flow control valve 236 that is in fluid communication with a two-way port 218AB of the accumulator 18. A second two-way port 216AB2 of the fluid device 216 is in fluid communication with the two-way flow direction control valve 231. The two-way flow direction control valve 231 is connected to a flow control valve 237 that is in fluid communication with a two-way port 217AB of the reservoir 17.

[87J The energy recovery system I B may further comprise a fluid coupling 249 configured to he coupled to the drive shaft 148 of the vehicle 100 as shown in Figure 1. The fluid coupling 249 comprises an input port 249A in fluid communication with a second output port 218B of the accumulator 18 and an output port 249B in fluid communication with a second input port 217A of the reservoir 17. The fluid coupling 249 is arranged in such a way that it can he made to decouple the engine 101 from a section of the drive shaft 148, as will he described in further detail later on.

1881 In the embodiment shown, the fluid device 216 is coupled to the drive shaft 148. The fluid device 216 may be implemented as individual units attached to each wheel when all wheel drive is required. The energy recovery system 1B is not limited by the number of wheels/units utilised and can be used in other applications which may require multiple wheel/driven devices in excess of four to be driven at a time. Current mechanical methods for all wheel drive make it complex and impractical to he implemented in a system which requires more than four wheels to be driven at the same time. The embodiment show in Figure 1 is a simplified version which can be implemented in existing vehicles with minimal modifications so that the vehicle may not need any additional modified components in the suspension setup, steering elements, etc. The advantage would be that the existing optimised parameters for a standard vehicle such as spring rate, rebound, etc. can he used. This would help to keep the research and development cost down as the base vehicle need not he extensively altered for the system's implementation.

1891 It would he understood that the energy recovery system 1B is not limited in any way by the embodiment show in Figure lwhich serves as an illustrated example to facilitate a detailed understanding of the various components and functions of the energy recovery system. The system may employ one or more pressure relief valves and flow check valves so as to ensure the fluid flow is as desired and in a controlled manner.

Variable shaft speed mechanisms/connections [90] Referring to Figures 2, 2A, 2B, 2C and 2D, various embodiments of possible connection mechanisms that may be positioned between the shaft B of the turbine 3 and the shaft A of the compressor 2 are shown. The connection mechanisms allow existing turbochargers to be modified so as to be able to have variable shaft speeds.

[91] Figure 2A shows a connection mechanism in the form of an electric clutch arrangement 2A1 used between the shaft A of the compressor 2 and the shaft B of the turbine 3. The electric clutch arrangement 2A1 is configured to disconnect the shaft A of the compressor 2 from the shaft B of the turbine 3 as required or in pluses so that the speed between the compressor and turbine can he maintained and controlled as required by the ECU 111.

[92] Figure 2B shows a connection mechanism in the form of a gear arrangement 2B I used between the shaft A of the compressor 2 and the shaft B of the turbine 3. The gear arrangement 2B1 is configured to vary the compressor 2 and turbine 3 shaft speeds so that they may he efficiently operated at different speeds with respect to each other. The gear arrangement 2B1 may also be employed to bring down the high operational speeds of the turbine 3 or compressor 2 shafts so that they can be mated to fluid components or mechanical components at lower operational speeds and vice-versa.

1931 Figure 2C shows a connection mechanism in the form of a fluid coupling arrangement 2C1 used between the shaft A of the compressor 2 and the shaft B of the turbine 3. The fluid coupling 2C1 can be designed to have a gearing advantage or disconnect the shaft B of turbine 3 from the shaft A of the compressor 2 with the help of ECU 111 controlled solenoid valves Al and Blwhich are normally closed. When the valve Al is opened, fluid from the fluid coupling 2C1 is vented out into the reservoir 17 which causes the fluid coupling 2C1 to slip as there is insufficient fluid level for it to effectively function. When the valve E I is opened, this will cause tluid to flow into the fluid coupling 2C1 from the accumulator 18 increasing the level of fluid in the fluid coupling 2C1. Since sufficient fluid is now present in the fluid coupling 2C1, it engages the shafts A, B connecting them together. The valve operation can be controlled to enable the engagement and disengagement of the turbine 3 and compressor 2 shafts as and when required by the ECU 111.

1941 The introduction of a fluid coupling arrangement 2C1 between the shaft B of the turbine 3 and the shaft A of the compressor 2 can allow a certain degree of slip such that the turbine speed would he allowed to spool higher before it starts to drive the compressor 2 thus increasing the starting torque available to drive the compressor 2. A bigger compressor 2 can be mated to the same turbine to make use of this increased starting torque. This would he beneficial in large turbocharged engines which have noticeable turbo lag as the compressor cannot he brought up to speed quickly, since here the turbine is spooled up to higher rpms without the need to drive the compressor's shaft A, before it engages with the compressor shaft taking advantage of the momentum generated by the turbine wheel rotating at high rpms. Once it has gathered sufficient speed, the turbine's shaft B drives the compressor's shaft A with a multiplied torque.

[95] It would be understood that an alternative coupling mechanism and/or torque converter may be utilised, instead of the fluid coupling mechanism described above, which functions in a similar way as described above.

1961 Figure 2D shows a connection mechanism in the form of a freewheel mechanism 201 used between the compressor's shaft A and the turbine's shaft B. The freewheel mechanism 201 can he placed between the turbine's shaft B and compressor's shaft A in a location that is suitable. For example, the freewheel mechanism 2D1 may be placed on the compressor's 2 side or in a central housing so that the heat from the turbine 3 and exhaust does not affect the freewheel mechanism 2D1.

[97] The freewheel mechanism 201 provides the ability, depending on the direction, to allow the compressor 2 or turbine 3 to rotate independently when it over speeds without affecting the other. Also the freewheel mechanism 2131 can he adjusted so that at a fixed torque it starts to slip. For example, this can he used on the compressor's 2 side so that the outlet pressure is always constant and when the pressure exceeds a pre-set value the compressor wheel slips without affecting the turbine 3 at the said condition. The milli ne's 3 speed is allowed to continue increasing rotationally and storing the energy kinetically. When the compressor 2 is acted by a pressure below the pre-set value it again mates with the turbine 3. This process takes place continuously, maintaining the compressor wheel speed so that it works at a particular torque which effectively translates to a particular boost level. This can be implemented on the turbine's 3 side so to prevent back pressure build-up.

[98] Current hydraulic assist turbochargers have the compressor and turbine shaft fixed. As a result, when the compressor is assisted by the hydraulic fluid it also needs to drive the turbine side which requires additional assistance as the mass of the turbine wheel must also be driven. This also marginally increases the spool up time and the amount of assist needed. The mismatched turbine speed can also prevent the optimal flow of exhaust gases and create back pressure when operated in such conditions. The introduction of the freewheel mechanism as described above would allow the compressor to be driven at high speed by the hydraulic fluid without affecting the turbine speed or vice-versa depending on the direction of rotation of the freewheel mechanism.

[99] The hydraulic energy recovery system 1B can be used to assist the operation of an existing hydraulic turbocharger modified with the use of one or more of the connection mechanisms mentioned above and the stored energy from the accumulator can he used to drive the compressor of the hydraulic turbocharger.

Thermal Isolation Arrangements [100] Referring to Figures 3A, 3A1 and 3B, different mechanical coupling arrangements for coupling the turbine and compressor in the hydraulic system 1 in accordance with the invention are shown. It should he appreciated that the illustrated representations are for illustration purposes and are not limited by the orientation in the verticallhorizontal axis or at an inclination to either axis shown. The mechanical coupling arrangements allow the compressor and turbine to be thermally isolated from each other, and can be used in conjunction with the connection mechanisms between the turbine and compressor shafts of Figures 2A to 2D to give a thermal isolated and variable speed turhocharging system.

[101] Referring in particular to Figure 3A, a thermally isolated arrangement using a mechanical flexible cable 3A1 is shown. The mechanical flexible cable 3A1 comprises an inner rotating shaft/cable portion 3A2 and an outer fixed shaft/cable portion 3A3 (see Figure 3A1). The mechanical flexible cable 3A1 is used to connect the compressor's 2 shaft and turbine's 3 shaft after passing through speed varying mechanisms 3A4 to lower (or vary) the speed if necessary. The speed varying mechanisms used may he a mechanism as mentioned above such as an electric clutch, a gearbox, a torque convertor, a freewheel mechanism etc. 11021 The flexible cable arrangement enables the compressor 2 and turbine 3 to he placed separately with relatively less physical constraint. The coupling between the turbine 3 and compressor 2 also may be made by a shaft/cable portion arranged such that the turbine 3 and compressor 2 are far apart such that they can he placed in the exhaust and inlet side respectively taking advantage of the thermal isolation.

[103J It would he understood that other mechanical flexible couplings may he utilised instead of the embodiment described above such as a universal joint etc. 11041 Referring to in particular Figure 3B, a thermally isolated arrangement using a rigid shaft is shown. The turbocharger is arranged such that the turbine 3 and compressor 2 are on the same shaft C far apart from each other such that they are thermally isolated from each other. Bearings bh 1, hh2, hh3, hh4 are provided on the shaft C which are configured to facilitate the balancing of the long shaft C. The said setup also can he used for any turbocharger and is not limited by the technology mentioned herein.

11051 A suitable speed variation mechanism as previously described may he used with the shaft so that the compressor and turbine can he operated at different speeds. This arrangement would give the possibility for the turbine and compressor temperatures to be more effectively managed with the ability for speed variation, thermal isolation, elimination of piping losses and low cost implementation.

ADDITIONAL FUNCTIONS OF THE FORCED INDUCTION SYSTEM IA

[106] While the forced induction system lA has been described in relation to its main function, may be utilised for one or more additional functions as outlined below.

Minimising blow off valve operation [107] The compressor 2 may be prevented from needing to frequently operate a blow off valve to vent boost pressure in order to regulate the boost pressure in the inlet manifold. This is accomplished by having the ECU 111 monitor the compressor's 2 speed via the speed sensor 28 and receive additional data from the throttle position sensor 141, the boost pressure sensor 143, the manifold air temperature sensor 142 and the accelerator pedal position sensor 133.

[108] When the compressor starts to build excessive pressure in the inlet manifold 106, the ECU 111 regulates the flow displacement valve 8 which increases the displacement flow required to drive the fluid motor 4. The fluid motor 4 would thus require more fluid to he inputted to operate at the same rpm. The fluid motor 4 as a result would run at a lower speed, reducing the speed of the compressor 2 mated to it thus reducing the manifold pressure in the process. The compressor's 2 speed can further be controlled by the ECU 111 with the flow control valve 10 which can he opened or closed to assist in regulating the input fluid flow to the fluid motor 4. The speed of the fluid motor 4 directly affects the boost produced as the compressor is driven by the fluid motor 4. The compressor 2 can thus he effectively operated at any rpm as per air flow requirement since the compressor's 2 shaft speed can he varied independently to the turbine shaft speed.

[109] In addition to regulating the compressor's 2 speed, the flow control valve 54 may he closed in order to develop a pressure build up in-between the valve 54 and the output port 4h of the fluid motor 4. 'Phis reduces the speed of the compressor 2 due to the fact that, as the fluid motor 4 tries to overcome this pressure built up its operational speed drops as it consumes more power to overcome this increased pressure built up. The flow control valve 54 can he controlled by the ECU 111 so that it enables a further reduction in the speed of the compressor 2 as required and in the process would reduce the boost pressure in the inlet manifold 106.

11101 In the event where sudden regulation of the inlet pressure is needed, the blow off solenoid valve actuator 46 can be operated by the ECU 111 to ensure a more effective control over the boost pressure. The air vented by the actuator 46 may be recirculated or passed into the exhaust pipe as a means to cool the exhaust system if needed. The vented air may be stored in an additional air reservoir which can supply the stored air back into the inlet manifold under high boost demand conditions if required. This can he done by the introduction of an additional valve that is opened and closed by the ECU 111.

Minimising waste gate operation [111] The turbine 3 may be prevented from over speeding by the ECU 111 which monitors the turbine speed via speed sensor 26. When the turbine 3 starts to over speed, the ECU 111 regulates the fluid flow displacement solenoid valve 9 which increases the displacement flow output of the fluid pump 5. The fluid pump 5 would thus require more input power to drive it which would put additional load on the turbine shaft thus reducing the speed in the process. The speed reduction is converted into additional fluid pressure which is stored in the accumulator 18 via second input port 18al1 from the output port 5a of the fluid pump 5.

[1121 In addition to regulating the turbine's 3 speed, the flow control valve 55 may be closed in order to develop a pressure build up in-between the valve 55 and the output port 5B of the fluid pump 5. This reduces the speed of the turbine 3 due to the fact that, as the fluid pump 5 tries to overcome this pressure build up its operational speed drops. The flow control valve 55 can be controlled by the ECU 111 so that it enables a reduction in the speed of the turbine 3 as required.

11131 If rapid speed reduction of the turbine 3 is required, the ECU 111 can operate the waste gate solenoid valve 47 to vent out pressure as required to keep speeds in check. Thus the turbine speed can be controlled by the ECU 111, and since the turbine shaft speed is not related to the compressor shaft speed, the turbine can effectively function at any rpm at which it is-efficient. The turbine 3 can contribute fluid pressure to the system even when the compressor 2 is operated at different speeds. Thus the exhaust gases would always he contributing to drive the turbine 3 productively.

Drivine the compressor at low speeds [114] As previously mentioned, the compressor 2 and turbine 3 are capable of being independently operated at different speeds which serves as a major advantage over existing systems.

[115] The compressor's 2 speed is sensed by the sensor 28 which sends the signal to the ECU I I1. The compressor's 2 speed, as mentioned previously, is controlled by varying the flow displacement control solenoid 8 and the fluid flow control valve 10 of the fluid motor 4.

[116] When the engine 101 operates at low speeds, the turbine 3 driving the fluid pump 5 may not produce enough fluid flow output to be able to effectively drive the fluid motor 4 at high speeds. In such situations, the ECU 111 can control the fluid flow via the flow control valve 10, making use of the additionally stored fluid pressure from the accumulator 18 to drive the fluid motor 4 coupled to the compressor 2 such that turbo lag becomes non-existent.

11171 The function can also he called at conditions such as high engine speeds when the turbine 3 may not he able to operate the compressor 2 to elevated speeds so that a very high boost pressure is obtained. This gives the possibility of the compressor's 2 boost pressure to be adjusted as per requirements as the boost produced would be proportional to the speed at which the compressor is driven.

11181 There have been hydraulic assist turbines which supplement the compressor's operation in high demand conditions and to prevent turbo lag. but the turbine and compressor are on a common shaft. As a result when the compressor is operated at high speeds this results in the turbine also being operated at high speed which may not always be desirable. The forced induction system IA of the invention helps to overcome this and make the compressor's 2 operation independent of the turbine 3.

Reduced operational speeds and improved linear performance [119] The ability to have the compressor 2 and the turbine 3 operated independently gives the ability to replace the conventional centrifugal compressors in vehicles which operate at high rpms with blowers which operate at significantly lower rpms whereas the turbine still may for example employ a centrifugal type turbine running at different speeds, thus it is possible to have different types of compressor/turbine working together because of the variable shaft speed. This would reduce temperature rise caused due to the compressor being operated to compress the air. In addition, lower rpm operation increases reliability and reduces unbalance forces which are amplified due to high speed operation. The blower can be of a positive displacement type giving a more linear performance.

[120] The manufacturing cost of the compressor would also reduce as it would be less complex to machine and cast blower components compared to the radial compressor components currently used. The simple design would also make mass production possible leading to cheaper units. The same can also he implemented on the turbine side with the design of the turbine components.

Dynamically variable cylinder pressure [1211 The forced induction system's IA implementation can give the ability to have a dynamically variable cylinder pressure by filling the combustion chamber with varying air volumes so as to have a varying degree of cylinder pressure. This along with current developments in fuel injection technology can be combined to make the engine more fuel efficient while also reducing emissions.

[122] The compressor's 2 boost is increased as required by the regulation of the fluid motor's 4 speed which is mated to the compressor 2 so that the cylinder has an increased volumetric efficiency resulting in an increased combustion pressure. When the compressor's 2 speed is reduced, the boost pressure is reduced resulting in less volumetric efficiency in the cylinders of the engine thus a decrease in the combustion pressure. This is possible due to the compressor's 2 boost being able to be varied as required by the ECU 111 as per the setup of the forced induction system IA as described above.

[123] There have been several attempts by automotive manufactures to implement variable compression ratio systems but all the variants have additional moving parts which are difficult to implement into existing engine designs and would also bring down the reliability of the engine. The system proposed here achieves the similar result as with variable combustion ratio by using a system capable of providing a dynamically variable combustion pressure. The engine would be designed with the least compression ratio/and or combustion pressure required and when operational would be brought up to the required dynamic combustion pressure by increasing the cylinder volumetric efficiency by increasing the pressure and volume of the air flow entering the cylinder as required. The volume of the air output can be adjusted according to the demands as the speed of the compressor 2 can be increased or decreased independent of the engine operating speed and turbine speed. This could also serve to reduce engine power as required giving the opportunity to vary the air flow along with existing fuel injection technologies which regulate fuel flow.

[124] The implementation of the above said technology would make it possible to have low combustion pressures during vehicle starting conditions which would result in smooth operation and smaller size starting components such as starter motors, batteries etc., which in addition to reducing the costs would also increase the life of the starting components as they would have to deal with lower varying loading forces. The system would he highly beneficial for start and stop vehicles which require frequent use of the starting components which are currently oversized to meet the additional operational loading.

Independently variable cylinder air control [125] The engine 101 has individual throttle valves present in the runners 121, 122, 123 and 124 of the inlet manifold 106 for the cylinders I. 2, 3, 4 respectively. The individual throttle bodies consist of butterfly valves Tv 1, TV2, -IV3, and TV4.

[126] When cylinders are deactivated, for example cylinder 2 and 4, it would be beneficial that a reduced quantity of air flow is transferred into the cylinders. This is because increased air flow increases the combustion pressures within the cylinders creating engine braking and acts as an engine parasite, reducing the benefits of the cylinder deactivation due to the fact that a certain percentage of additional fuel would he consumed to counter the engine braking produced for overcoming the combustion pressures in the deactivated cylinders.

11271 In such conditions, the throttle valves of cylinder 2 i.e. TV2 and cylinder 4 i.e. TV4 can he closed proportionally by the ECU 111 controlling the volume of air flowing into the cylinders. This will reduce the volumetric efficiency which indirectly results in a lower combustion pressure reducing the engine braking effect. When the function is operated in conjunction with the dynamically variable combustion pressure function as mentioned above, the effects would he more significant.

[128] The ECU 111 could further reduce the fluid flow to the fluid motor 4 so as to have a reduced operating speed which indirectly reduces the volume of air flow entering into the inlet manifold 106 so as to compensate for the reduced air flow requirements of the engine when the cylinders 2, 4 are deactivated. This controlling of the air flow as required is possible as a result of the forced induction system's lA ability to vary the air flow as needed which is not possible in conventional turbocharger systems.

[129] The throttle valves TV1, TV2, TV3, and TV4 can further be opened and closed as required by the ECU 111 so that each cylinder within the same engine may have a different volumetric efficiency, hence a different combustion pressure depending on the way in which the air flow to the cylinders is controlled by the ECU 111. As the combustion pressure differs, the force exerted by the piston on the mating components, for example the crankshaft, varies. This would give the opportunity for the engine to be balanced perfectly and dynamically if necessary by having a closed loop system in which strain sensors supply the ECU 111 with the data relating to the forces acting within the cylinder and the ECU 111 can control the throttle valves so that the above mentioned process is carried out. This would serve as a tool for balancing and smoothing out engine vibrations perfectly. This can be used in engine configurations where the cylinders are difficult to balance properly due to an uneven number of cylinders such as in 3 cylinder engines etc., or when the balancing needs to he improved upon.

Variable engine braking [130] When mild braking is needed, the ECU 111 can be utilised to increase the compressor's 2 speed in order to increase the air flow to the engine 101. The increase in compressor speed dynamically increases the combustion pressure so that the increased combustion pressure can provide increased engine braking which would act as additional load so that the vehicles speed reduces and there is less wear and tear in the braking system. The fuel supply may he stopped or reduced while the said process is carried out.

11311 When a car is travelling at say a constant speed, it would require lesser amounts of power to maintain the speed. In such situations, the fuel is reduced/cut but in current setups it is not possible to reduce the air flow so as to have a fixed air/fuel (a/f) ratio but at varying quantities. The forced induction system lA of the invention can he employed to reduce the air quantity as required in conjunction with current fuel injection systems which can meter the fuel flow as required, thereby giving the same a/f ratio but at smaller quantities thus reducing the cylinder pressure. This would also reduce engine braking as a result when cruising, thereby maximising the fuel efficiency of the vehicle. If required the fuel and air flow can be completely reduced so that minimal engine braking is present while cruising thus minimising the resultant load due to engine braking which would help to conserve the momentum of the vehicle.

11321 The advancements in engine management systems have made it possible to run extremely lean mixtures without increasing emissions or combustion temperatures. The forced induction system IA gives the possibility for the engine to be a lean engine, operate at different a/f ratio and at a dynamic compression pressure as required.

Thermal cycling and emission control [133] When desired, the fuel can be completely cut which results in air entering the cylinder and exiting via the exhaust. As the air leaves the exhaust, the air absorbs the heat from the engine internals and the exhaust system bringing down the temperatures. This effectively can he used as a tool to cool and maintain the engine and exhaust system at optimal temperatures.

[1341 Highly tuned and modified cars can use such a system as they comprise smaller cooling components for the benefit of weight reduction and smaller air passages for effective aerodynamics at high speed operations. Smaller cooling components and smaller air passages can cause heat and temperature rise in low speed traffic conditions due to insufficient air flow for the cooling components since other surrounding vehicles especially in bumper to bumper traffic prevent the air from freely circulating over the cooling components.

11351 The possibility of controlling the engine parameter functions as desired with the implementation of the above mentioned features, makes it is possible to operate the engine as a lean burn engine at low engine temperatures or when the temperatures of the exhaust and catalytic convertors have to be increased and then once the temperatures are reached can be made to operate normally at set air/fuel ratios. It is known that at lean air/fuel ratios, the combustion temperatures and heat generated increases and this would give the opportunity to increase the temperature of the engine quickly as needed thus increasing the efficiency and reducing emissions as the engine is operated at optimal running temperatures. If the temperature needs to be lowered the thermal cycling method mentioned above can he used. 'thus the operational temperatures of the engine can he effectively controlled so that both increasing the temperature and decreasing the temperature of the engine is possible to some extent.

Functions of the energy recovery system 1B [136] The energy recovery system 1B may be utilised for one or lore functions as outlined below.

Energy recovery [137] When the brake pedal 115 is pushed, the sensor 114 picks up the position of the brake pedal 115 and sends the information to the ECU 111. The ECU 111 then activates the magnetic clutch 13 as required to couple the fluid pump 12 to the engine 101 thereby drawing fluid through the input port 12A from the reservoir 17 via the first output port 17B1 of the reservoir 17. The fluid pump 12 thus produces pressurised fluid which flows via the output port 12B through the flow control valve 56 into the first input port 18A1 of the accumulator 18.

[138] The fluid pump 12 consumes engine power in order to compress the fluid which slows down the speed of the vehicle 100. The ECU 111 controls the displacement of the fluid pump 12 via a flow displacement solenoid valve 11 thereby giving the ECU 111 the ability to vary the displacement of the fluid pump 12 as required. This would indirectly affect the load placed on the engine 101 reducing the speed of the vehicle 100 as the wheels are connected to the engine via the gearbox and a reduction in the speed of the engine would indirectly reduce the speed of rotation of the wheels coupled to it.

11391 The braking force can he varied as needed by the operation of fluid pump 12 in a similar method as previously described for the fluid pump's 5 operation. The ECU 111 controls the solenoid valve 11 based on the inputs from the accelerator pedal position sensor 133, the gear position sensor 138, the throttle position sensor 141, the steering wheel position sensor 145 and the engine speed sensors 129, thereby braking the car with the required force.

[140] If increased braking force is required then the flow control valve 56 can be closed as this would lead to excessive pressure build up in-between the output port 12B of the fluid pump 12 and the valve 56. This would increase the load placed to drive the fluid pump 12 as 11101e power is required to overcome this created fluid pressure in the output port, and will create drag slowing the engine down. Additionally the fluid device 216 can be made to act as a fluid pump by activating the flow switching valve 230 which reroutes the fluid flow from the first two-way port 218AB of the accumulator 18 passing through the flow control valve 236 to the second two-way port 216AB2 of the fluid device 216 and activates the flow switching valve 231 which redirects the fluid flow from the first two-way port 216AB1 of the fluid device 216 passing through the flow control valve 237 then into the reservoir 17 via the first two-way port 217AB of the reservoir.

[141] When the fluid device 216 acts as a fluid pump, directional valve 230 opens fluid flow from the fluid pipe 230B to the fluid pipe 230A, and closes the flow to fluid pipe 230C. Also the directional valve 231 opens fluid flow from the fluid pipe 231C to the fluid pipe 231 A and closes the flow to fluid pipe 231 B. If further braking is required, the flow valve 237 can be closed so that it would create pressure build up creating more braking force as previously described for the fluid pump's 12 braking when the flow control valve 56 is activated.

11421 The reversible fluid device 216 now functions as a fluid pump. The rear wheels 108, 109 are slowed down due to the drag created in driving the fluid pump 216 which supplies pressurised fluid flow to he stored in the accumulator 18 to be used later on. The degree of the braking can be further controlled by placing more load for driving the fluid device 216 by varying the displacement of the fluid device 216 by use of the displacement flow control solenoid 235 which is controlled by the ECU 111 in a similar method as described above for the operation of fluid pump 12 based on the requirements of braking force needed.

Combined Makin [143] In sport/high performance vehicles, when the vehicle needs to slow down from high speeds, conventional disc brakes tend to wear down quickly and build up excessive heat. To overcome this, most sport/high performance vehicles include an aerodynamic brake etc. to support and reduce the load on the conventional brakes. The braking energy is not recovered in the above mentioned methods.

[144] The energy recovery system 1B may be utilised as a hydraulic braking system in such vehicles and will not be subjected to such wear since the fluid is capable of handling the additional load without any adverse effects. The braking energy is converted into fluid pressure and stored in the accumulator 18. The fluid control system also builds up the braking resistance progressively preventing wheel lock ups and can he used in emergency situations which will cause less wear and tear to the existing braking components as it absorbs a majority of the load. This would help the vehicles brake more effectively and safely while also recovering the otherwise wasted energy in the process.

[145] The energy recovery system 1B can be linked up with existing braking systems to work in conjunction with them to provide even better braking response at low speeds by the use of a solenoid activated brake mechanism acting on conventional brake arrangements such as disk brakes etc. As a result the braking can be controlled more effectively by the ECU 111 which controls various solenoid valves to bring out the function.

Transmitting of power to wheels [146] The energy recovery system 1B can act as a transmission system for the engine power to the wheels, replacing the need of a separate transmission or can be used along with a suitable setup such as with the fluid pump 12 and fluid device 216, both of which are of the variable displacement type and in fluid communication with each other indirectly due to the system connections as described above. The pumps can he controlled by the ECU 111 as required through the solenoid valves 11 and 235 as described above.

[147] "I-he rear drive shaft 148 is attached to fluid device 216 which can he driven from the stored fluid pressure in the accumulator 18 transferred via the first two-way port 218AB passing through the flow control valve 236 managed by the ECU 111. The control valve 236 can adjust the flow so as to control the speed at which the motor of the fluid device 216 rotates. The fluid then passes through the direction control valve 230 and enters via the first two-way port 216AB1 of the fluid device 216 and exits via the second two-way port 216AB2 of the fluid device 216, passing through the fluid flow direction valve 231 then through the fluid flow control valve 237 and entering the reservoir 17 through two-way port 217AB causing the wheels to move in the forward direction.

If the wheels need to be driven in reverse, the ECU 111 controls the fluid flow direction valves 230 and 231 such that the fluid pressure in the accumulator 18 is transferred via first two-way port 218AB passing through the flow control valve 236 to the direction control valve 230, then enters the fluid device 216 via second two-way port 216AB2 and exits via the first two-way port 216AB1 through valve 231 and enters into the reservoir 17 through the two-way port 217AB causing the wheels to move in the reverse direction.

[148] For forward motion/operation as a fluid motor, directional valve 230 opens fluid flow from the fluid pipe 230B to the fluid pipe 230C, and closes the flow to fluid pipe 230A. Also the directional valve 231 opens fluid flow from the fluid pipe 231 B to the fluid pipe 231 A and closes the flow to fluid pipe 231C.

[149] For reverse motion/operation as a fluid pump, directional valve 230 opens fluid flow from the fluid pipe 230B to the fluid pipe 230A, and closes the flow to fluid pipe 230C. Also the directional valve 231 opens fluid flow from the fluid pipe 231C to the fluid pipe 231 A and closes the flow to fluid pipe 231B.

[150] When a high gear is needed, the fluid pump 12 can be adjusted to have a high displacement flow output while the reversible fluid device 216, which now functions as a fluid motor, can be adjusted to have a low displacement flow input so for every rotation of the fluid pump 12, the reversible fluid device 216 would rotate a few degrees more, giving a high ratio gear.

[151] When a low gear is needed the fluid pump 12 can be adjusted to have a low displacement flow output while the reversible fluid device 216 can be adjusted to have a high displacement flow input so for every rotation of the fluid pump 12, the reversible fluid device 216 would rotate a few degrees less, giving a low ratio gear.

[152] The fluid device 216 can be used to assist the vehicles motion while accelerating or maintain cruising speed as required by means of the ECU 111.

Multiple-wheel drive arrangement [153] In certain configurations, the variable fluid device 216 arrangements can be duplicated such that it is associated with the front wheel axle or directly coupled to each individual wheel such that it can be made to drive each wheel individually. The association with each wheel would give the vehicle incorporating the system the ability to have all wheel drive with the speed of each wheel being able to he varied and controlled independently by the addition of more flow control valves and solenoids as required. It would be understood that any number of wheels may be driven at a time so there is no limitation to the system's arrangement.

Traction control [154] The fluid device 216 when setup for all wheel drive as mentioned above is also capable of controlling wheel speed and operating them individually which gives the energy recovery system I B the ability to effectively have a control of the vehicles traction. When the ECU 111 senses a loss of traction due to the relative change in speed of a particular wheel compared to the other wheels indicated by the wheel sensors 150, 151, 152 and 153 etc., energy recovery system 1B is able to redirect the fluid flow accordingly to the other wheels such that wheel speeds are constant across all the wheels in order to offer maximum traction all the time. The braking can also be controlled in a similar manner as described above such that the wheel with the most traction is given more braking force. Since the hydraulic braking is gradual it would prevent wheel lockup.

Cruise control [155] The energy recovery system 1B may be utilised for cruise control due to the fact that the transmission of the vehicle power and braking of the vehicle is controllable by the ECU 111.

11561 The braking, and as a result of which the wheel speed, can be controlled by the ECU 111 by switching on and off the fluid pump 12 as previously described. The ECU 111 also has the ability to adjust the flow control solenoids, flow displacement control solenoids and manage other vehicle controls. As such, vehicle motion based on the inputs from the accelerator, throttle position etc. can be regulated by the ECU 111 in order to control the speed of the vehicle effectively. The operation of the fluid device 216 can also he regulated by the ECU 111 so as to drive the vehicle 100 forward in a desired speed.

Traffic crawling 11571 The hydraulic energy recovery system 113 can be effectively used in heavy traffic situations by using the stored fluid pressure from the accumulator 18 to drive the fluid device 216 to propel the vehicle forward without the need for the engine to be in operation. The benefits would not only be less wear and tear of the transmission components but also a huge reduction in emission.

11581 The vehicle incorporating the energy recovery system 1B would benefit from the ability to have a comfortable and smooth drive in traffic as the vehicle motion would be controlled by fluid pressure. The operation of the vehicle would also be less noisy as the internal combustion engine need not be operational. The engine when not in operation would be prevented from overheating which is prone to occur in heavy traffic as there is a reduced flow of air through the front grills across the engine at low speeds.

[159J The energy recovery system 1B would he highly beneficial in buses operating in cities as most of the hum operators are trying to cut hack on the emissions and increase fuel efficiency of their buses. The additional wear and tear of vehicle components such as gearbox clutches etc. due to frequent starting and stopping can also he reduced or eliminated.

Automatic function in manual transmission [160] The main advantage of an automatic transmission is its ease of operation in traffic as it reduces the need for manual gear changes and clutch operation. The introduction of the energy recovery system 1B would give manual transmission vehicles the ability to behave like an automatic transmission vehicle in traffic conditions as the gear can he in neutral while power transmission to move the vehicle is carried out hydraulically as described above.

11611 The engine may he switched off or kept operating as required so that other vehicles systems such as air conditioning, battery charging etc. may still function. The engine may also be kept operating so as to drive the hydraulic pump 12 to keep it operational so that when the fluid pressure in the accumulator 18 falls below the critical value the accumulator is supplied with pressurised fluid.

[162] The benefit of such an arrangement is that the engine can he operated at a constant load and rpm whereas if the system is not in place every time when the vehicle is to be moved forward, it would require the operation of the clutch which would load the engine requiring the use of the accelerator to compensate for the load. Hence there would load variations which would cause fluctuations in the operational rpm as well as wear and tear to the components of the transmission and clutch.

[163] Torque convertors and fluid coupling used in automatic transmission have low efficiency at low speeds whereas the said hydraulic components are very efficient at low speeds. The system's introduction would give the advantages of an automatic transmission to a manual transmission vehicle, and also reduce the emissions as the engine can be more optimally managed.

Hill ascent and descent [164] The vehicle 100 can be assisted while climbing hills by the fluid device 216 functioning as a fluid motor connected to the transmission helping underpowered vehicles cope with steep gradients and also with the ability to effectively control the speed of ascent.

11651 During hill descent, the vehicle's speed of descent can he effectively controlled by the ECU 111 by regulating the use of the fluid device 216 which is operated as a pump arrangement making braking possible.

The braking energy which would have been wasted otherwise is harnessed and sent to the accumulator 18 where it is stored as fluid pressure for later use. The operation of the system would reduce the wear and tear of the brake components. The ECU 111 can operate the brakes and control the accelerator to maintain the desired speed automatically if pre-set. Overheating of the brakes is a common problem in mountainous terrain due to frequent use of the brakes, here this is minimised by the use of the hydraulic braking system which reduces the stresses placed on the conventional braking system of the vehicle.

Engine decoupli ng [166] The vehicle while cruising can be allowed to freewheel by disengaging a section of the drive shaft 148 from being connected to the differential 117. The fluid coupling 249 present on the drive shaft 148 has a fluid input port 249A which leads to a flow control valve 251 which is in fluid communication with the second output port 2188 of the accumulator 18. The fluid coupling also comprises a fluid output port 249B which leads to a flow control value 252 which is in fluid communication with the second input port 217A of the reservoir 17.

11671 Operation of the flow control valve 252 vents out the fluid from the output port 249B of the fluid coupling 249 to the second input port 217A of the reservoir 17, based on the level to which it is opened by the ECU 111. When the level of fluid in the fluid coupling 249 falls below the required minimum operational fluid level, the fluid coupling 249 starts to slip effectively disengaging the engine 101 from the section of the drive shaft 148.

[168] When the power transmission is needed via the drive shaft 148 to the differential 117, the valve 251 is opened proportionally and controlled by the ECU 111 which forces fluid from the accumulator 18 via the second output port 218B to the input port 249A of the fluid coupling 249. This raises the level of the fluid within the fluid coupling 249 to the minimum operational level thus preventing the hydraulic coupling from slipping and thus transmitting the power through the drive shaft 148 to the rear differential 117.

[169] The vehicle 100 at constant speed would not require any additional power apart from the energy required to overcome the rolling resistance of the tyres, aerodynamic drag and mechanical losses. A substantial amount of the mechanical loss is due to engine braking and consumes a lot of energy. The engine can he effectively decoupled from the driveshaft as required by the ECU 111. This feature can also be used in combination with some of the other features mentioned above so that when power is transmitted hydraulically and when the vehicle is in gear, it is not affected by the section of the drive shaft 148 which is connected to the engine 101.

The engine thus can be decoupled as required by the ECU 111 as mentioned above.

[170J Inn-eduction of the fluid coupling arrangement alone would bring about huge improvements to the fuel efficiency of the vehicle. The drawback to which could he the possible increased use of the brake which would wear down the braking system significantly, but this problem can be overcome as the vehicle is equipped with a hydraulic fluid braking system which does not cause any wear and tear and the braking energy can be stored in the accumulator 18 for further use.

11711 The ECU I I I can control the operation of the fluid coupling or level of slip as required further improving the system efficiency. The hydraulic coupling may he replaced with other elements such as a mechanical freewheel etc. to provide the same or similar benefits as described above.

Differential [172] If the fluid device 216 is mated separately to each wheel. When taking a corner the wheels are capable of being driven individually at different speeds, the need for a separate differential is eliminated as the wheel speeds may be varied as required to compensate for a differential. The system can be further optimised so that the relative wheel speed between the wheels is controlled based on information received via the steering wheel position sensor, accelerator position sensors, wheel speed sensors etc. making it possible to go around corners perfectly.

11731 The system also has the capability to function as an automated parking system if operated along with parking sensors and current parking systems so that the wheels are controlled by the ECU 111 along with the brakes automatically by the ECU 111 to help turn the vehicle in a smaller radius.

Independent suspension and steering 11741 The scope of having the driving fluid devices directly mounted on the wheels eliminates the need for additional methods of power transfer to the wheels such as the use of CV joints, coupling etc. This makes it possible to have a fully independent suspension when power transmission and steering is carried out as there are no rigid constraints such as drive shafts.

[175] When travelling over uneven road surfaces or when the vehicles suspension is worn or when the steering components are not aligned, the vehicle will tend not to follow a straight line. Since the speed of the vehicle's wheels can be directly controlled by the ECU 111, the wheel speeds can be varied in real time so that the vehicle motion can he corrected so the vehicle can travel in a straight line. This allows the system to he used along with the existing lane departure technology to provide automatic correction of the vehicle so that it maintains its lane. It is also possible to introduce rear steering so there is no rigid axle in a similar manner as the front. The hydraulic fluid stored in the accumulator may be used to control actuators that can adjust the ride height or other parameters such as stiffness, rebound etc. in real time as they can he actively controlled by the ECU based on the inputs from the various sensors.

[176] As indicated above, the hydraulic system 1 in accordance with the invention comprises many benefits and may be utilised to carry out many functions.

[177] The ability to optimise the turbine and compressor shaft speeds separately, the thermal independency of the units, along with the energy recovery system capable of harnessing the energy lost while braking the vehicle can be used to drive the compressor up to required boost levels (as described in detail above) or propel the vehicle forward. This would improve fuel efficiency and reduce emission in situations such as urban driving where there is frequent braking and stop/start situations.

[178J The hydraulic system in accordance with the invention would provide huge benefits if implemented in motorsport as it gives the tuners the ability to manage the turbine and compressor individually. The use of the braking energy recovery system, given the frequency of usage of the brakes in racing, would make this a valuable technology as considerable energy which is otherwise wasted can he harnessed and reused.

[179J The use of the additional technological innovations mentioned above as a result of the implementation of the subsystems 1 A and 1B would substantially benefit the current automotive industry and other industries which would require an energy recovery system with the ability to drive shafts of the components mated to turbines at different speeds as required.

11801 Although the invention has been described above with reference to one or more preferred embodiments, it will be appreciated that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.

[181] The addition of flow regulators, one way valves, pressure release valves, safety valves, flow control valves, solenoids actuators, electronic/electrical pressure control devices, additional sensors and other components into the hydraulic system 1 are within the scope of the invention.

11821 The hydraulic system 1 can be made simpler with the fluid pump 12 carrying out partial functions such as braking energy recovery with the forced induction system IA implemented. The incorporation of a power steering pump to the system 1 means that some components of the system can be eliminated where the power steering pump can serve to substitute their function.

[183] The use of the fluid pressure from the hydraulic accumulator to drive other components such as power steering, brakes, hydraulic actuators which may he used for window regulation, suspension setup, ride height control, roof mechanism operations in convertibles etc. are possible.

11841 The addition of electromagnetic coupling to the fluid device 216 so it can he engaged and disengaged by the ECU 111 is also possible.

[185] While the hydraulic system I and components thereof have been described with reference to their implementation in a four wheeled vehicle, it is not limited thereto and may be adapted for use in other vehicles with a different number of wheels such as motorcycles, trucks, off road vehicles etc. and/or applications such as military applications, marine applications etc. 11861 The system or its components may he adapted to he utilised in other fields such as wind mills, power stations, etc. where there is a turbine such that it is driven by a working fluid such as air, water, steam etc. which is coupled to another unit such as generator, motor, pump etc. where it is beneficial to provide variation in the shaft speed between the two connecting elements. The system for example can he used in hazardous environments such as nuclear power plants where it is necessary to isolate the turbine and power generation components so they can be easily maintained with less risk of radiation leak and added safety for localisation of disasters as hydraulic lines can be used to transmit the rotation of the turbine to the power generation units in an different location/room.

Claims

CLAIMS1. A forced induction system for an engine comprising: a compressor configured to supply air to an inlet of an engine; and a fluid control system operatively connected to the compressor; wherein the fluid control system comprises a first fluid motor configured to drive the compressor, and a flow control valve; and wherein fluid flow to the fluid motor is controllable by the flow control valve so that the speed of the first fluid motor, while driving the compressor in use, can be controlled by the operation of the flow control valve.
2. A forced induction system according to claim 1 wherein the fluid control system further comprises a fluid pump configured to be driven by the engine.
3. A forced induction system according to claim 2, further comprising a magnetic clutch system configured to couple the fluid pump to the engine.
4. A forced induction system according any preceding claim, wherein the fluid control system further comprises a hydraulic power steering pump.
5. A forced induction system according to any one of claims 2 to 4, wherein the forced induction system is a hydraulic supercharger system for an engine.
6. A forced induction system according to any one of claims 2 to 5, further comprising an accumulator configured to store energy as fluid pressure, the accumulator comprising a first input port in fluid communication with an output port of the fluid pump, and a first output port in fluid communication with an input port of the first fluid motor.
7. A forced induction system according to any one of claims 2 to 6, further comprising a fluid reservoir, the fluid reservoir comprising a first output port in fluid communication with an input port of the fluid pump, and a first input port in fluid communication with the output port of the first fluid motor.
8. A forced induction system according to any one of the preceding claims, further comprising a speed varying mechanism positioned between the compressor and a mating component.
9. A forced induction system according to any one of the preceding claims, wherein the compressor is thermally isolated from any surrounding heat source.
10. A forced induction system according to claim I. further comprising a turbine configured to he operated by exhaust gases of the engine.
11 I. A forced induction system according to claim 10, wherein the fluid control system further comprises a first fluid pump configured to he driven by the turbine.
12. A forced induction system according to claim 10 or 11, wherein the system is a hydraulic turbocharger system for an engine.
13. A forced induction according to claim 11 or claim 12 when dependent on claim 11, wherein the fluid control system further comprises a second fluid pump configured to be driven by the engine.
14. A forced induction system according to claim 10 or any claim directly or indirectly dependent on claim 10, further comprising a speed varying mechanism positioned between the turbine and the compressor or the turbine and a mating component and/or the compressor and a mating component.
15. A forced induction system according to claim 14, wherein the speed varying mechanism comprises an electric clutch, a gear box, a hyperbolic gear drive, a torque convertor, a fluid coupling, or a free wheel mechanism.
16. A forced induction system according to claim 13 or any claim directly or indirectly dependent on claim 13, further comprising an accumulator configured to store energy as fluid pressure, the accumulator comprising a first input port in fluid communication with an output port of the first fluid pump, a second input port in fluid communication with an output port of the second fluid pump, and a first output port in fluid communication with an input port of the first fluid motor.
17 A forced induction system according to claim 13 or any claim directly or indirectly dependent on claim 13, further comprising a fluid reservoir, the fluid reservoir comprising a first output port in fluid communication with an input port of the first tluid pump, a second output port in fluid communication with an input port of the second fluid pump; and a first input port in fluid communication with the output port of the first fluid motor.
18. A forced induction system according to claim 10 or any claim directly or indirectly dependent on claim 10 wherein the turbine and the compressor are thermally isolated from one another.
19. A forced induction system according to any one of the preceding claims, further comprising one or more sensors, pressure relief valves, and flow check valves; and an electronic control unit configured to control one or more parameters and/or components of the forced induction system.
20. A forced induction system according to claim 19, further comprising one or more solenoid valves and/or solenoid valve actuators for facilitating the electronic control unit in controlling the one or more parameters and/or components of the forced induction system.
21. An energy recovery system comprising a fluid accumulator; a fluid reservoir; a fluid motor; a fluid pump; and a fluid control system comprising one or more flow control valves, pressure relief valves, and flow check valves; wherein the fluid accumulator comprises an input port configured to he in fluid communication with an output port of the fluid pump and wherein the fluid reservoir comprises an output port configured to be in fluid communication with an input port of the fluid pump.
22. An energy recovery system according to claim 21, further comprising a fluid device, the fluid device comprising a first port in fluid communication with a two-way port of the fluid accumulator and a second port in fluid communication with a two-way port of the fluid reservoir.
23. An energy recovery system according to claim 22, wherein the fluid device comprises a fluid pump or a fluid motor.
24. An energy recovery system according to any one of claims 21 to 23, further comprising a fluid coupling/a torque convertor/a freewheel mechanism/a freewheeling clutch/an overrunning clutch attachable to a drive shaft of a vehicle, wherein the fluid coupling/torque convertor is configured to be operated to decouple the engine of the vehicle from the drive shaft as required by operation of valves that allows the fluid coupling/torque convertor/freewheel mechanism/freewheeling clutch/overrunning clutch to be filled with fluid from the accumulator and/or drain fluid to the reservoir as required.
25. An energy system according to any one of claims 21 to 24, further comprising one or more sensors, and an electronic control unit configured to control one or more parameters and/or components of the energy recovery system.
26. An energy recovery system according to claim 25, further comprising one or more solenoid valves and/or solenoid valve actuators for facilitating the electronic control unit in controlling the one or more parameters and/or components of the energy recovery system.
27. A combined forced induction and energy recovery system for a vehicle comprising a forced induction system as claimed in any one of claims 1 to 20; and an energy recovery system as claimed in any one of claims 21 to 26.
28. A turbocharger system for an engine of a vehicle comprising: a turbine configured to be operated by exhaust gases of an engine; a compressor configured to supply compressed air to an inlet of the engine; and a speed varying mechanism positioned between the turbine and the compressor or the turbine and a mating component and/or the compressor and a mating component.
29. A turbocharger system according to claim 28, wherein the speed variation mechanism comprises an electric clutch, a gear box, a hyperbolic gear drive, a torque convertor, a fluid coupling, or a free wheel mechanism.
30. A turbocharger system according to claim 28 or 29, wherein the turbine and compressor are thermally isolated from each other, and comprising a flexible cable arrangement coupling the turbine to the compressor, the flexible cable comprising an inner rotating cable portion and an outer fixed cable portion.
31. A turbocharger system according to claim 28 or 29, wherein the turbine and compressor are thermally isolated from each other on a common shaft and said shaft is mounted on one or more bearings configured to balance the shaft.
32. A turbocharger system for an engine of a vehicle comprising: a turbine configured to he operated by exhaust gases of an engine; a compressor configured to supply compressed air to an inlet of the engine: and a flexible cable arrangement coupling the turbine to the compressor, the flexible cable comprising an inner rotating cable portion and an outer fixed cable portion, wherein the turbine and compressor are thermally isolated from each other.
33. A turbocharger system for an engine of a vehicle comprising: a turbine configured to be operated by exhaust gases of an engine: and a compressor configured to supply compressed air to an inlet of the engine, wherein the turbine and compressor are thermally isolated from each other on a common shaft and said shaft is mounted on one or more bearings configured to balance the shaft.
34. A turbocharger system according to claim 31 or 33, wherein the common shaft comprises a universal joint or a bevel gear.
35. A vehicle comprising an energy recovery system according to claim 25; wherein the one or more sensors are located within the vehicle, and the electronic control unit is also configured to control one or more parameters and/or components of the vehicle.
36. A vehicle according to claim 35, further comprising one or more solenoid valves and/or solenoid valve actuators for facilitating the electronic control unit in controlling the one or more parameters and/or components of the vehicle and/or energy recovery system.
37. A vehicle according to claim 35 or 36, further comprising a fluid coupling before the transmission or on a draft shaft driven by an engine of the vehicle, the fluid coupling configured to selectively couple or decouple a section of the draft shaft from the engine.
38. A vehicle according to any one of claims 35 to 37 when dependent on claims 21 and 25 directly, further comprising a fluid device associated with each wheel of the vehicle, each fluid device comprising an input port in fluid communication with a two-way port of the fluid accumulator and an output port in fluid communication with a two-way port of the fluid reservoir.
39. A method of controlling one or more parameters and/or components of a vehicle comprising the steps of: - providing in a vehicle, a forced induction system according to claims 19 or 20 or a combined forced induction and energy recovery system according to claim 27 when dependent on any claim dependent directly or indirectly on c I aim 19; - positioning the one or more sensors within the vehicle and configuring the one or more sensors to measure data in relation to one or more components of the vehicle; - configuring the electronic control unit to collect and process data in relation to the one or more components of the vehicle based on data measured by the one or more sensors; - configuring the electronic control unit to control or adjust one or more parameters and/or components of the vehicle and/or forced induction system in response to the collected and processed data.
40. A method of controlling one or more parameters and/or components of a vehicle as claimed in claim 39, wherein the electronic control unit is configured to control or adjust one or more parameters and/or components of the vehicle and/or forced induction system in response to the collected and processed data in order to carry out one or more of the following functions: - minimise operation of a blow off valve; - minimise operation of a waste gate; - drive the compressor at low speeds; -improve the linear performance between the turbine and the compressor; - dynamically vary the cylinder pressure within and/or air flow into one or more cylinders of an engine of the vehicle.