CN102687309A - Energy control - Google Patents

Abstract

The present invention provides an energy storage device comprising a flywheel having at least one input. According to one aspect, in use, the flywheel input is arranged to supply energy to the flywheel, wherein energy is recovered from engine exhaust. According to another aspect, there is provided an apparatus comprising a charge boost device, in use, for providing inlet boost to an engine. The apparatus further comprises a flywheel, wherein the flywheel is arranged to provide energy to drive operation of the charge booster device.

Description

energy control

technical field

This application relates to energy control. In particular, the application relates to the use of flywheels for the supply, storage and recovery of energy.

Background technique

Energy conservation and optimal use of energy are major considerations in building and operating modern vehicles and machines. Users are increasingly demanding efficiency and the greatest possible output at the lowest possible cost. Considerations in the cost/output balance include financial and environmental factors. Additionally, there is a need to improve the power and speed of vehicles and machines, while providing a comfortable and user-friendly feel. Further, engines, motors and other equipment tend to become more compact and streamlined.

There are many known ways to deal with the smoothing discussed above. For example, as user demands for environmentally friendly vehicles increase and regulations on carbon emissions become stricter, hybrid vehicles are becoming more and more popular. As known to those skilled in the art, a hybrid vehicle uses a combination of two or more different power sources to propel a vehicle or other powered machine. In the field of motor vehicles, the most common hybrid is the hybrid electric vehicle (HEV), which combines an internal combustion engine (ICE) with one or more electric motors. Depending on the power demand at any given moment, either or both the ICE and the electric motor may be employed to provide power to the output of the vehicle. Along with the electric motor, a chemical energy storage system is provided so that during periods when the electric motor is not being used to power the vehicle output, it can be operated as a generator to generate and store electrical charge in the chemical energy storage system for later use. Known chemical energy storage systems may consist of a single type of chemical unit, or may include any combination of units with different chemical formulae. All such chemical energy storage systems are referred to herein as chemical "batteries".

Problems exist in known hybrid systems due to the high cycle frequency of hybrid battery system charge levels caused by, for example, regenerative braking and recuperation in typical vehicle usage segments and the high power flow associated with these operations Deterioration of battery condition is accelerated, thereby limiting system lifetime. As a result, batteries in conventional hybrid systems are often limited. Typically, the battery chemistry may have to be replaced twice during the life of a known hybrid electric vehicle. Further, battery cycling may be limited by a protective control system that controls power distribution and/or charging in a hybrid system. The effect of this protection limitation is to weaken the _CO2 emission reduction efficacy of the corresponding hybrid system.

Another known method for optimizing energy supply and conversion from stored chemical energy to torque, especially in ICE-powered motor vehicles, is the use of turbochargers and superchargers. As will be known to those skilled in the art, a turbocharger recovers exhaust energy to drive a compressor and increase inlet charge pressure to the engine. The supercharger device uses the torque delivered by the engine to drive the compressor to increase the inlet charge pressure. In practical use, however, both devices have associated disadvantages. A turbocharger, being a passive device, is only operable when there is sufficient exhaust flow to drive the boost system. In contrast, a supercharger is an active device in that it is usually crank driven, and therefore does not suffer from these operational limitations like a turbocharger. However, a supercharger does introduce a parasitic loss of engine energy, thereby reducing its overall efficiency in terms of reducing fuel consumption.

One aspect of user comfort and experience targeted for motor vehicle applications is the "torque break" sensation caused by a shift event on an automated manual transmission vehicle. While this type of transmission is very efficient, this torque interruption feeling during shifting includes user's shift comfort and drivability. According to known methods, during a shift interruption of an automated manual transmission, the electric motor can be used to meet the torque demand in order to improve the driving smoothness for the user. However, in order to power such an electric motor, an additional energy supply is required within the vehicle, and further, energy loss is unavoidable during the energy conversion stage between electric energy and kinetic energy. Dual clutch and automatic transmissions limit the torque interruption during shifting, however, these transmission types are more expensive and/or inherently less efficient than automated manual transmissions due to the losses associated in providing power to the drive system .

As discussed above, in order to optimally balance the cost and output of a vehicle or machine, it is desirable to utilize the available energy as much as possible and to prevent energy from being dissipated, eg, as heat.

Flywheels are known for storing energy in the form of kinetic energy, such as those used in vehicles. The use of flywheels is known to store energy that would otherwise be converted to heat in the vehicle's braking system when the vehicle is decelerating, the stored energy being used subsequently to accelerate the vehicle when required. However, the known implementations of the flywheel present a problem of how to charge the flywheel during the initialization phase and at its low energy point. It is possible to use the electric motor flywheel charging system. However, it should be appreciated that this is not an ideal solution as it introduces additional energy demands on the electrical energy storage system within the vehicle while failing to reduce exhaust energy losses from the vehicle.

Accordingly, there is currently a need for devices and methods that optimize energy usage in vehicles and other machines without compromising factors important to users, such as comfort, cost efficiency, and environmental friendliness.

The application is set forth in the claims.

Because, according to one aspect, there is provided an energy storage device comprising a flywheel, wherein said flywheel is arranged to have energy recovered from engine exhaust gases input thereto, thereby enabling an efficient and self-contained storage and energy recovery method. That is, an energy storage device utilizes the energy already present in a conventional engine, vehicle or machine without the need to provide additional energy.

By providing exhaust gas recovery, exhaust gases are quickly and efficiently directed from the engine output to the flywheel for storage. Advantageously, a Tesla turbine or turbocharger can be used for exhaust gas recovery. Many conventional vehicles already include turbochargers, so that an energy storage device according to the present aspect requires minimal rearrangement of the engine configuration to be useful.

By providing a clutch in the exhaust path between the exhaust gas recovery and the flywheel, a method of controlling exhaust gas input to the flywheel is provided. Furthermore, by providing the flywheel in a vacuum device, the flywheel can operate without hindrance from friction caused by air resistance, and the device is further optimized.

Since the flywheel can be mechanically linked to a variable ratio system and/or coupled to the power output of the engine, the flywheel can be used as an energy source in conjunction with the engine to, for example, provide hybrid vehicle drive. Furthermore, by arranging the flywheel so that it can operate as a mechanical battery for an engine, vehicle, machine or other device in the installation, the energy efficiency benefits of the flywheel are optimized. That is, the flywheel is not limited to a single function that requires its use periodically, but rather, during operation, the flywheel can be used more often, when energy is available and/or is needed in the engine, vehicle, or machine , to recover and/or supply energy.

Since, according to another aspect, there is provided an apparatus comprising both a charge booster device and a flywheel to provide energy to drive the operation of the charge booster device, an energy efficient, effective and simple A method of increasing inlet air pressure in an engine. The device is flexible and has several different applications, including operation with known superchargers and/or with known turbochargers.

By providing input supply energy to the flywheel, the flywheel can be initially charged and fully charged, thus providing a reliable and continuous mechanical battery for driving the charge boost in the engine. Because, the flywheel can be powered by existing energy sources within the engine, vehicle or machine (e.g., driveline power, engine exhaust energy, auxiliary machinery, chemical batteries or electric motors), thereby providing enhanced energy efficiency because no Additional energy is required to run the unit. This feature has the further advantage that the device requires only relatively simple modifications to known engine systems to enable the intelligent harvesting and storage of energy in these known engines.

Since, a flywheel according to this aspect can be placed in a turbocharger exhaust loop, a self-renewing and self-contained method of energy recovery and storage is provided. Furthermore, because the flywheel can be used as the sole energy source for the air boost device, or as a supplemental energy source in combination with the engine, flexibility is provided regarding the size of the flywheel for a particular application. In addition, additional options regarding flywheel control schemes are provided. The flywheel may operate alone or in conjunction with the engine to drive a charge boost device, thereby optimizing boost pressure in the engine and thus enhancing engine output and overall efficiency.

Description of drawings

Embodiments according to the present application will be described below in conjunction with the accompanying drawings, wherein:

Embodiments according to the present device will be described with reference to the following figures:

Figure 1 shows a known flywheel arrangement;

Figure 2 shows a possible configuration for providing exhaust gas energy to the flywheel;

Figure 3 shows the relationship between boost and engine load of a conventional turbocharger device;

Figure 4 shows a possible layout for dual-mode operation with a chemical battery in parallel with a flywheel battery;

Figure 5 shows an exemplary control flow for the arrangement of Figure 4;

Figure 6a shows the energy flow of the arrangement of Figure 4 during load equalization or regenerative braking;

Figure 6b shows the energy flow of the arrangement of Figure 4 during power assist from the motor to the ICE;

Figure 6c shows the energy flow for the arrangement of Figure 4 during plug-in charging;

Figure 6d shows the energy flow for the arrangement of Figure 4 during slow charge sustain;

Figure 6e shows the energy flow of the arrangement of Figure 4 during low power flywheel power maintenance and high power motor operation;

Figure 7a shows the relationship between vehicle speed and chemical battery state of charge of a chemical battery used alone in a hybrid vehicle;

Figure 7b shows the relationship between vehicle speed and chemical battery state of charge in the arrangement of Figure 4;

Figure 8a shows a possible engine configuration for flywheel torque filling;

Figure 8b shows another similar configuration for flywheel torque filling;

Figure 8c shows yet another similar configuration for flywheel torque filling;

Figure 8d shows a possible control scheme for flywheel torque filling;

Figure 9a shows a possible configuration of an auxiliary flywheel device coupled to the ICE;

Figure 9b shows a possible configuration of an auxiliary flywheel device coupled to the ICE using a split-path IVT layout;

Figure 10a shows an arrangement in which the flywheel device is coupled to the host vehicle clutch and upstream of the ICE of the transmission;

Figure 10b shows an arrangement where a flywheel device is coupled to the ICE at the transmission input;

Figure 10c shows an arrangement where the flywheel is coupled to the ICE at the transmission output; and

Figure 10d shows an arrangement in which the flywheel is coupled to the rear axle system.

overview

In summary, according to one aspect, an apparatus for storing energy in the form of kinetic energy in a flywheel is provided. The device comprises at least one input to the flywheel, wherein the input directs energy that has been recovered from the engine exhaust to the flywheel. Thus, the energy normally dissipated when the exhaust gases are released into the air is recovered and stored in the flywheel for future use. Thus, the flywheel is arranged to act as a mechanical battery which is initially and during operation charged by the engine exhaust.

Any suitable exhaust recovery arrangement may be provided to direct exhaust from the engine output point to the flywheel. For example, Tesla turbines and turbochargers may be used. Preferably, a clutch is provided between the exhaust gas recovery and the flywheel to control the power input to the flywheel. The flywheel and/or clutch may be mechanically connected to the variable ratio system, and from the variable ratio system, mechanically coupled to the power output of the engine. Because the flywheel acts as a mechanical battery, the flywheel can provide energy to a mechanical coupling point, thereby enabling hybrid control of the vehicle or any suitable combination of engines and/or flywheels to meet the energy output requirements at any given moment.

The flywheel is not limited to acting as a mechanical battery for the engine supplying it with exhaust, but can additionally or alternatively provide energy to other devices including, but not limited to, superchargers, turbochargers, chemical batteries, and electric motors. The flywheel and associated energy recovery and supply equipment can be suitably controlled to ensure that the flywheel is always optimally charged and that when energy is needed, the flywheel can supply energy in an efficient and rapid manner.

Accordingly, an arrangement and associated method and control scheme is provided that recognizes the use of existing energy in an engine, vehicle or device, storing this energy for future use, and reusing the stored energy at the most appropriate time thereafter this possibility. The devices involved are mechanically simple, readily available and can be arranged in any suitable configuration depending on user needs or other constraints.

In summary, according to another aspect, an apparatus, method and control scheme are provided for using a flywheel to provide energy and thus drive operation of a charge booster device. The charge boosting device powered by flywheel energy may be any suitable known type of supercharger or turbocharger. Since the flywheel acts as a mechanical battery capable of long-term storage of energy in the form of kinetic energy, the air-boost device can be driven regardless of instantaneous engine speed or power. Furthermore, because the flywheel is a self-contained energy store, using the flywheel to power the gas boost device does not result in parasitic losses of power from the engine or elsewhere.

During operation, any suitable energy source may be used to charge the flywheel initially and at other times. Preferably, the flywheel is driven using energy already available in the engine, vehicle or machine in which the flywheel is placed, but in these systems this available energy is usually dissipated rather than reused. For example, the flywheel may be driven by engine exhaust energy and/or using power from the vehicle driveline or driveline. According to one embodiment, the flywheel may even be driven by the energy of the exhaust gas emitted from the wastegate of the turbocharger, thus creating a closed loop autonomous energy storage and recovery system.

A flywheel can be implemented to run a charge-boost device instead of using conventional means to run such a device, eg engine power or exhaust gas energy, or it can be used as an auxiliary energy source, resulting in a hybrid energy system.

The flywheel can be properly controlled so that at any given moment, the proper amount of energy is delivered to the charge boost device, depending on the instantaneous conditions of the engine, the mass of the atmosphere, and the pressure requirements. Thus, the flywheel enhances and facilitates the operation of the charge boost device in order to achieve optimum boost within the range of engine loads in a simple yet smart and efficient manner.

Detailed ways

Figure 1 shows a typical existing flywheel arrangement. A substantially circular central metal support part 1 may be mounted axially on the central support (eg shaft 3). At least one composite ring 2 is mounted on the central support part 1 . In the flywheel shown in Figure 1, the composite ring 2 is from carbon fiber filament winding. As will be known to those skilled in the art, and as discussed above, a flywheel device such as that shown in Figure 1 can be used as a mechanical battery to store kinetic energy for use in, for example, a motor vehicle.

exhaust flywheel

Figure 2 shows a possible arrangement for providing energy to a flywheel in a vehicle for storage. To optimize the operation of the flywheel 12 by eliminating friction caused by air resistance, the system 10 includes the flywheel 12 preferably disposed in a vacuum device 14 . Outside the vacuum device 14 , connected to the flywheel 12 is a clutch 16 . The clutch 16 employed may be any suitable type of simple clutch, even an electromagnetic clutch.

To provide energy to flywheel 12 and initially drive flywheel 12 , and/or fully charge the flywheel battery system, input 18 is provided to flywheel 12 via clutch 16 . This input directs exhaust energy from the internal combustion engine of the vehicle providing the flywheel system 10 to the flywheel 12 and causes the exhaust energy to be stored in the flywheel 12 . The arrangement also includes a suitable output 20 for the exhaust so that the supply of exhaust energy to the flywheel 12 can be steered and controlled.

It should be understood that a substantial portion of the exhaust gases generated in a vehicle are typically released into the air. Releasing the exhaust from the vehicle instead of reusing it wastes the energy in the exhaust. Consequently, the vehicle must be operated to generate more usable energy within it, thus resulting in further exhaust emissions from the vehicle, thereby creating potential environmental problems. In contrast, the present embodiment utilizes the energy of the exhaust gas and allows the energy of the exhaust gas to be stored for future use.

Any suitable means for recovering exhaust gas energy and directing it directly to the flywheel 12 may be provided. For example, a Tesla turbine plant (not shown) may be employed to use the exhaust as a power agent and recover exhaust energy therefrom.

As is well known to those skilled in the art, a Tesla turbine (or disk turbine) is composed of two or more disk elements fixed to a shaft and spaced axially from each other along the shaft by a gasket or other suitable means. composition. In use, the flow of gas or liquid in a Tesla turbine is radial, following a circular or helical path. In this embodiment, exhaust gas flow to clutch 16 and flywheel 12 can be controlled by varying the axial spacing of the Tesla turbine's disks to increase or decrease the gas passing through them and input to clutch 16 per unit of time volume.

In the arrangement shown in Figure 2, there is no Tesla turbine. Instead, exhaust gases are directed to clutch 16 and flywheel 12 via a variable geometry turbocharger (VGT) ( 17 ). VGTs and other turbocharger devices are widely used to recover exhaust gas from vehicles and use it to boost pressure at the engine inlet. However, due to the direct drive nature of the turbocharger, the turbocharger cannot utilize or store energy from the exhaust gas supplied to it. According to this embodiment, a VGT may be advantageously employed instead of, or in addition to, performing its normal function of providing pressurized air to the engine to supply the engine via the flywheel. 12 to utilize excess exhaust gas energy so that the energy therein can be stored for future use.

A clutch 16 is provided between the flywheel 12 and a variable ratio system 22 as shown in FIG. 2 . As discussed further below, a variable ratio system may include a transmission device such as a continuously variable transmission (CVT) or an infinitely variable transmission (IVT) or an equivalent electric motor device. The variable ratio system 22 in FIG. 2 leads to the driveline of the vehicle such that the flywheel arrangement 12 is mechanically coupled to the vehicle's internal combustion engine (ICE), thereby providing a mechanical hybrid drive system. However, the flywheel 12 may alternatively or additionally be used for purposes including direct drive, charging other battery types, and/or powering vehicle outputs other than the drivetrain, while still being arranged to be powered by the vehicle's exhaust. flow to charge.

In the arrangement shown in Figure 2, the clutch should be able to be used to synchronize the flywheel (12) input and the turbine element. Therefore, it should participate in the sliding state and thus dissipate a small amount of energy.

A lightweight low inertia dry single disc or cone clutch can be used as a straightforward solution. More compact solutions include electromechanical powder clutches, which are used on a/c compressors and superchargers, but usually have a rather low speed range, or wrap spring clutch devices, which are a single to the device) will only provide twist to the flywheel to prevent any loss of drag from the turbine when the engine is in a non-"boost" state.

When synchronized by the variable ratio system (22), the turbine will spin at flywheel speed, and thus variable inlet geometry can be used to adjust Optimize turbine efficiency.

And thus providing a mechanism for recovering and storing engine exhaust energy for future use. The flywheel 12 according to the present embodiment does not require any additional energy source such as an electric motor in order to initiate charging or to top it up, but instead provides the power of the flywheel system by utilizing existing exhaust energy that is wasted in conventional vehicle systems. Continuous auxiliary charging. Unlike turbochargers, flywheel performance is not limited by turbo lag. Further, the energy in the flywheel 12 does not need to be used immediately, but can be stored for future use in various applications in the vehicle, as will become apparent further from the description below. However, since the mechanism shown in Figure 2 uses the exhaust gas flow which has kinetic energy in it, and provides this kinetic energy to also be stored as kinetic energy in the flywheel, losses due to conversion between energy types are reduced.

flywheel-assisted turbo

According to one embodiment of the above aspect, the flywheel 12 may be placed in the wastegate loop of a turbocharger. As is familiar to those skilled in the art, a turbocharger is a passive device placed in the exhaust stream of a vehicle or engine for the purpose of directing the energy of the exhaust gas to a compressor to increase the pressure therein. However, if there is excess mass flow through the turbine itself, back pressure will be created which increases the exhaust manifold pressure of the engine beyond optimum levels, thereby reducing engine efficiency. To avoid this, the turbocharger has a wastegate to release excess gas from it, thus helping to optimize both engine boost and exhaust manifold pressure at different system operating points.

In conventional arrangements, the energy in the exhaust released from the turbocharger wastegate is not utilized, but is lost as exhaust is emitted from the vehicle. According to the present aspect, the waste gas energy problem is solved. Energy in the excess exhaust gas emitted from the wastegate of the turbocharger is directed to the flywheel to provide input thereto. Immediately or later, the flywheel 12 may be used to assist in driving the compressor of the turbocharger. Thus, through the combined use of the turbocharger and flywheel 12, exhaust energy is intelligently harvested and utilized to assist the operation of the supercharger. This makes the supercharger work more efficiently, as can be understood from FIG. 3 .

Referring to Figure 3, it shows the boost-load relationship of a conventional supercharger. It can be seen that a turbocharger only produces the optimum ideal boost for the associated internal combustion engine in a small engine load range. However, using the flywheel 12 to drive the compressor of the turbocharger, and in combination with the turbocharger turbine, optimizes boost over a wide load range and thus flattens the curve shown in FIG. 3 . As a result, improved turbocharger efficiency is achieved.

Flywheel Assisted Supercharging

In addition to being operable for use with a turbocharger, a flywheel according to the present embodiment may be used to drive a supercharger arrangement of a vehicle. As briefly discussed above, known supercharging devices operate by using engine power to drive the compressor of the supercharger and boost the charge pressure in the vehicle. This direct use of engine power causes parasitic losses, thus compromising the potential efficiency of the vehicle in operation.

According to the present aspect, it has been recognized that a flywheel device can be used to drive a charge boosting device, such as a supercharger, to boost engine charge pressure without the need to draw power directly from the engine, thereby avoiding the device associated parasitic losses. As discussed above, exhaust gas energy can be used to charge the flywheel. Alternatively, energy may be recovered from the vehicle's driveline (eg, during regenerative braking or engine load leveling) and stored in an auxiliary flywheel device for use in driving a supercharger. Energy can be recovered from the drive train through any suitable mechanical linkage, such as a transmission, also discussed above.

In operation, the supercharger is coupled to a driveline of a vehicle. The flywheel acts as a torque supply for the supercharger, thus allowing the energy stored in the flywheel to be supplied indirectly to the driveline via the ICE. The mechanical linkage used between the flywheel and the supercharger may include a clutch as discussed above with respect to the exhaust-driven flywheel. Alternatively, an overrunning clutch can be used, traditionally using the turbine energy directly to drive the compressor when acceleration is required, and the flywheel energy can only be used when the turbine is idling (i.e. low engine speed). This requires an overrun clutch, which only drives in one direction, such as a wrap spring clutch. This is particularly effective for electromagnetic flywheel configurations where the speeds do not need to be matched and then the flywheel is charged from the turbine via the electrical path when the turbine is overboosted at high engine speeds. The flywheel also drives the compressor at low engine speeds via an electrical path.

Since, according to the present aspect, the flywheel is charged using drivetrain energy and/or exhaust gases, energy that would otherwise be wasted in conventional systems is utilized. By utilizing energy that would otherwise be wasted, the overall performance of the vehicle is improved. In particular, performance benefits are provided in terms of fuel consumption and vehicle emissions.

An auxiliary flywheel device according to this aspect can be used as the sole energy source for a supercharger or can be used as an extension to an existing supercharger energy source. For example, it can provide a power boost to the supercharger at low engine speeds, where using direct engine power is not preferred. Thus, since the flywheel is operable to enhance the power supply to the supercharger, the supercharger can provide the desired inlet pressure and mass flow into the ICE, regardless of the vehicle's operating engine speed, and with that time by the turbo system (if exists) to provide the same arbitrary mass flow rate. In other words, a flywheel-driven supercharger can provide optimal charge boost at any point in the vehicle's engine map. This is particularly advantageous for driving maneuvers such as driving away, which benefit from transient short-term Energy surge (surge).

Another advantage of a flywheel driven supercharger is that it allows for downsizing of the engine because the engine power density is increased during low exhaust mass flow events such as the exits described above. The reduced size results in reduced friction and pumping losses, thereby improving their efficiency. It is expected that by actively controlling mass flow into the engine cylinders to be optimal under all conditions, a flywheel-driven supercharger can result in reductions of up to 30% compared to an engine that is not even downsized. % fuel consumption. Downsizing the engine would thus enhance this potential fuel consumption advantage and also satisfy the growing consumer trend to achieve maximum performance from the smallest possible, compact and low-cost ICE.

The advantages of the flywheel driven supercharger described above are particularly pronounced in diesel engines, which typically have more compression and expansion in the chamber than gasoline engines air mass. As will be understood by those skilled in the art, the ideal inlet pressure is different for different engines and engine types, and can be derived, for example, from a design load map for such a vehicle.

dual mode battery

Figure 4 shows a possible layout of another flywheel according to a further aspect of the application. A configuration in which mechanical flywheel energy storage is used in parallel with a plug-in chemical battery system is shown. A mechanical battery 40 including a flywheel may be used, for example, to handle regenerative braking energy recovery, as an alternative to using a chemical battery 42 to perform this function. As discussed above, regenerative braking and recuperation during typical vehicle use segments tend to require high power and high frequency cycling for the battery system charge level of the hybrid vehicle or machine. This high frequency cycling has a significant negative impact on the chemical battery, compromising the health of the chemical battery and limiting the lifetime of the overall system.

According to an exemplary embodiment of the present aspect, the mechanical flywheel battery 40 operates in parallel with the chemical battery 42 to feed power electronics 44 of an electric motor 46 which in turn is arranged to provide power to the vehicle's hybrid drivetrain.

The arrangement shown in Figure 4 is not limited to the use of a flywheel as the main battery for regenerative braking. The flywheel battery 40 is advantageously used as the main battery for any rapid or short-term energy supply and/or recovery during vehicle use, while the chemical battery 42 is more suitable for low charge rates, ie slower, long-term energy supply and recovery. As will be understood from the additional figures discussed below, parallel chemical cells 42 and mechanical cells 40 according to the present aspect should be arranged and operated according to the same considerations as any other battery arrangement. That is, the available energy, power, and lifetime of the two batteries must be considered both individually and in combination. It should be noted that Fig. 4 also shows an embodiment in which the two batteries are arranged in parallel, but the two batteries could also be arranged in series, wherein the mechanical flywheel battery 40 is located between the chemical battery 42 and the transmission of the engine.

By co-using the mechanical flywheel battery 40 and the chemical battery 42, it is possible to reduce the overall cost of the battery power supply for the motor, since less power is required for a given power demand than if only the chemical battery were used without mechanical battery support. Small chemical batteries are used along with mechanical batteries. Alternatively, the lifetime cost of the power supply system can be reduced by increasing the lifetime of existing batteries by reducing the cycle frequency and/or the peak power demand of the chemical battery (or the peak power supplied to the chemical battery).

Referring to Figure 5, an exemplary control scheme can be understood. At a first step 510 , at a particular moment, it is considered whether power is entering or flowing out of the combined chemical and mechanical battery system, as shown in FIG. 4 . If, depending on the vehicle user needs and operating conditions at that time, power is flowing 512 from the battery system to provide power to the electric machine 46, then at step 514, the state of charge of the flywheel battery is considered. If the state of charge of the flywheel battery is found to be high 516 , then energy will be used from the flywheel battery 40 to power the motor 46 . If, on the other hand, the state of charge of the flywheel battery is low 518, energy from the chemical battery 42 will be used instead. If, as is often the case, the state of charge of the flywheel battery is medium when power output from the battery system is required, then it will be considered at step 522 whether the power required at that time is high or low. If the required power is high, enough energy to meet the demand will be taken 524 from the flywheel battery. However, if the required power is low such that no significant recharge cycles are required thereafter, then energy 526 to satisfy the power demand energy will be taken from the battery chemistry.

Returning to control step 510, if at step 528 it is determined that power is going into the battery system, the next consideration is whether this input power is occurring at low cycle power (e.g., during plug-in charging or slow charge maintenance) or during Occurs 530 under high cyclic load or power (eg, during regenerative braking or engine load leveling). For low cycle power inflows, energy will be stored in the chemical battery 42 . However, for high cyclic loads or powers, energy will be stored in the mechanical flywheel battery 40 . In this way, a control system is provided that optimizes the energy storage and recovery cycle characteristics of each battery type while ensuring that each battery is sufficiently charged to handle dynamically changing engine and vehicle demands.

Figures 6a to 6e further illustrate the exemplary control logic described above. Figure 6a shows the energy flow during load leveling or regenerative braking, during which energy is recovered and reused in short time intervals. As shown in Figure 6a, the energy previously present in the vehicle in the form of kinetic energy is recycled to the flywheel battery through the powertrain to avoid the cycle frequency of chemical battery charging and also advantageously avoid switching between the two types of energy instead of resulting energy loss.

In Figure 6b, the electric machine is used to boost the power supply from the ICE in a hybrid vehicle. The chemical battery 42 and the flywheel battery 40 are used to provide energy to the electric motor to meet the vehicle output needs at that time. Thus, it will be appreciated that the two battery types may be operated together or separately, depending on energy requirements and other control considerations at a given moment.

In Figure 6c, the chemical battery is charged via plug-in. The battery chemistry stores a long-term charge from plug-in mains power for later use.

In FIG. 6d it can be seen that energy can be supplied from the mechanical battery 40 to the chemical battery 42 . Figure 6d shows a slow charge maintenance where high power energy recovered from the vehicle tires and drivetrain is directed to the flywheel battery 40 and thereafter a low power charge from the recovered flywheel energy is provided to the chemical battery 42 for Long-term storage in chemical form. In this way, the current flow into the chemical cell 42 is minimized, and in turn, the power loss converted to heat in the chemical cell 42 is also minimized. The reduction in power loss in the chemical cell increases system efficiency and reduces the impact of detrimental thermal aging effects on the cell structure, as discussed further below.

Finally, FIG. 6 e shows the energy flow of the high power operation of the electric machine 46 . A chemical battery 42 (which is used to store energy in chemical form for long periods of time) charges the flywheel 40 to enable the flywheel 40 to provide energy for high power applications in the short term. As mentioned above, the efficiency of energy supply from flywheel batteries for high power applications is high compared to chemical batteries, so that when high power output from flywheel batteries is required, it is preferable to use flywheels alone The battery provides energy to the motor.

Figures 7a and 7b show typical battery charge cycles for the chemistry compared to vehicle speed for a conventional chemistry operating alone and a chemistry operating dual mode with a flywheel battery, respectively. As can be seen from these figures, by using energy from the flywheel battery during periods of time (e.g., rapid acceleration or rapid deceleration), thereby avoiding high power flow and high cycle frequency of charging in chemical batteries Better charging stability is achieved.

By way of further example, during regenerative braking via the motor/generator to the chemical battery, according to a transmission vehicle using the chemical battery alone (e.g., in the configuration shown in FIG. 4 ), the energy "round trip" ( Wheel-to-battery-to-wheel) efficiency is expected to be between 50% and 63%. In comparison, the efficiency of the same regenerative braking routine using a mechanical flywheel battery instead of a chemical battery as an energy storage source is expected to be around 84 percent. Thus, the dual-mode configuration (eg, shown in Figure 4) allows the long-term benefits of chemical batteries to be maintained, and at the same time, introduces new and advantageous efficiency effects by using flywheel mechanical batteries in parallel. Mechanical flywheel energy storage devices are inherently suitable for short-term energy storage and have no fundamental limit on the power they can deliver or receive. Thus, the present aspect takes advantage of the strengths of mechanical systems by preferably using them only for short-term energy storage. Although it can be expected that in special cases, flywheel batteries can help chemical batteries achieve long-term energy storage purposes.

In yet another advantage, the use of flywheels in dual mode with the chemical cells avoids high power flow into and out of the chemical cells, thereby preventing excessive temperature rise in the chemical cells. As will be understood by those skilled in the art, an increase in temperature over a period of time in a chemical cell will result in damage to the chemical cell. In addition, an increase in the internal temperature of the chemical cell will lead to a decrease in system efficiency because Ohmic losses in the subassemblies increase with the increase in impedance that corresponds to the increase in cell temperature.

The integral mechanical battery/chemical battery dual mode arrangement has an extended life expectancy compared to conventional chemical battery only arrangements. The dual-mode mechanical/chemical battery operation discussed here is not limited to use in conventional hybrid engines or electric vehicles. Rather, the principles of the present application can be more broadly applied to other vehicular machinery and equipment, including elevators and cranes.

Flywheel Torque Filling System

According to another aspect, a flywheel according to this embodiment may be used to "fill-in" output driveline torque on a vehicle during a "torque break" caused by a shift event on an automated manual transmission vehicle. moment. As will be understood from the description below, the fill layout and associated control method herein address the "torque break" feel (which is a problem for some users) by using flywheel energy during shift events to actuate or brake the transmission output to at least reduce or potentially eliminate the user's torque interruption sensation.

Figure 8a shows a possible arrangement for using stored flywheel energy to provide torque fill. A flywheel motor 80 is connected to a transmission 82 by a suitable isolating coupling 81 . Next, transmission 82 is mechanically coupled to the output of internal combustion engine 84 downstream of its transmission 86 so that both flywheel 80 and engine 84 can power the vehicle's final drive 88 .

Assuming the flywheel has constant inertia, the power supplied by or taken in by the flywheel is proportional to the flywheel's angular acceleration (ie, the rate of change of flywheel velocity). Thus, the rate of change of torque transmitted by flywheel 80 , via variator 82 , is inversely proportional to the angular velocity of the flywheel, and thus the proportional rate of change across variator 82 . However, it is contemplated that the control ratios on the transmission 82 alone will not provide sufficient control resolution to achieve the efficient flywheel torque fill required in accordance with the present aspect.

As will be apparent to those skilled in the art, most transmissions are designed to control speed ratios across them and are not designed for torque control per se. For transmissions where only speed can be controlled, using the transmission alone to control torque for short periods of time creates potential problems due to internal slippage of the transmission elements and possible delayed reaction of the transmission's conventional mechanisms. Therefore, in order to provide adequate control over the torque transferred to or taken from the driveline via flywheel 80 , an adjuster coupling 89 is provided between the transmission 82 and its final point of mechanical coupling 87 to the driveline 88 .

The use of a regulating coupling 89, including suitably placed in a ratio train as shown in Figure 8a, enables enhanced torque control not possible through the use of the variator 82 alone. The configuration shown in FIG. 8 a may use transmission 82 speed control to maintain consistent but limited slip across the clutches to minimize slip losses, but ensure consistent torque direction between flywheel 80 and final driveline 88 . This enables torque control resolution capabilities eg in the range of 0 to 100 Nm, but in a compact and cost-effective package. The torque control arrangement comprising the transmission 82 and modulating coupling 89 according to the present aspect provides a quick response in the range of less than 100 milliseconds, thus enabling torque to be provided to the driveline 88 when needed (particularly, during shift events). The moment-filled flywheel 80 is on for instant response. The arrangement shown in Figure 8a minimizes energy loss and thus ensures that most of the energy stored in the flywheel 80 is eventually converted into efficient torque fill as the vehicle requires over time.

In operation, the clutch included in regulating coupling 89 can direct and control braking torque and acceleration torque from flywheel 80 . That is, if the speed of the element on the flywheel side is lower than the speed of the element on the driveline side, braking torque will be produced by clutch action. Conversely, if the speed of the element on the flywheel side is greater than the speed of the element on the driveline side, acceleration torque will be produced by clutch action.

It should be appreciated that the magnitude of slip on the clutch will increase the degree to which energy is dissipated in the clutch. However, according to the present embodiment, minimal energy losses are sustained in the clutch device during operation of the clutch device, thereby providing slip limitation as well as transmission control. This allows for miniaturization of the clutch unit within the adjustment coupling 89 compared to a typical launch clutch on a separate ratio transmission vehicle. The clutches used in the adjustment coupling 89 according to the present embodiment may be of any suitable type including: electromagnetic clutches, passively cooled dry clutch units, passively cooled sealed wet clutch units with mechanical actuation devices, internal passive pumps Equipment wet clutch discs, or multi-disc clutches.

The control strategy for flywheel torque filling can be understood with respect to the arrangement of Figure 8a and further with respect to Figures 8b and 8c, Figures 8a-8c also showing a suitable arrangement according to the present aspect. The control logic includes consideration of whether engine power is on or off during a given shift operation, and also needs to consider whether the shift is an upshift or a downshift.

For a “power-up” upshift, the flywheel 80 requires acceleration torque to the driveline 88 . This enables torque variations at the vehicle wheels during a shift to be spread throughout the shift without compromising shift time or vehicle speed. Thus, advantages are provided over conventional powershift transmissions which must effectuate a torque change at the wheels during a first torque phase prior to a speed change, thus causing a sense of interruption to the user.

By way of illustrative example, Fig. 8d shows a possible control flow for a flywheel torque filling system according to the present aspect. The flywheel used may be of any suitable capacity. By way of example, the flywheel motor 80 may have a capacity of 400KJ, and the transmission 82 used may be a CVT with a capacity of 120KW. In such an arrangement, the flywheel can deliver 100KW to the drivetrain for 4 seconds. However, as will be appreciated by those skilled in the art, a typical shift takes only about a quarter of a second. Therefore, not all of the energy in the flywheel needs to be dissipated during any given shift and/or there may be overlap between the flywheel torque supply and the engine torque supply at the start of the shift and/or at the end of the shift.

As shown in Figure 8d, in an exemplary control flow, at step 810, the user first initiates a gear change, typically using a clutch pedal or other in-vehicle clutch control device. At step 820, the CVT then generates flow to transfer power from the flywheel to the driveline during a gear change. Once this power transfer is in place, at step 820 a gear change occurs in the engine. Once the gear change is complete, at step 840 the engine resumes responsibility for power transfer, and simultaneously or thereafter, at step 850 , power transfer from the flywheel and CVT is interrupted. At steps 840 and 850, during the transition from the transfer of energy from the flywheel back to the engine, the engine may be overrun in order to fully charge the flywheel for subsequent use.

For power-on downshifts, the considerations and control flow are similar. Therein, a conventional powershift transmission must effectuate a change in torque at the wheels during a torque phase after the speed has changed. However, by using the flywheel 80 to contribute to braking torque during a power-up downshift, torque changes at the wheels during a shift can be spread throughout the shift without compromising shift time or speed. Additionally, braking energy is collected in the flywheel for later return in accordance with the upshifting scenarios discussed above.

During a power-off downshift or upshift using the configuration shown in Figures 8a to 8c, the torque variation at the vehicle's tires can be spread over the entire roll-down period, thus ensuring a smooth roll-down behavior without shifting. block feeling. Advantageously, because the stuffing flywheel device is able to recover kinetic energy, depending on the drive mode of the vehicle, the main engine transmission can wait for positive torque before proceeding further.

Thus, the flywheel configuration and control method according to the present aspect provides a method of controlling the transmitted torque during a shift event in order to provide the user with improved shift comfort during the shift. Flywheel filling systems provide an efficient means of energy storage and recovery because the energy between the flywheel and drivetrain is maintained in the form of kinetic energy, thus preventing energy losses normally associated with energy conversion in vehicles and machines.

Since, according to the present aspect, no conversion between energy types is required, efficiency is increased. Thus, more energy is available throughout the system such that, potentially, no additional energy source is required for torque filling. Since the flywheel is arranged to provide energy to the drivetrain when needed and to recover energy from the drivetrain at other points during the vehicle's use cycle, it uses energy already present in the vehicle and therefore does not require an energy source to provide Its torque filling function. This provides a significant advantage over eg electric motor filling systems which require an additional energy source or at least an energy conversion stage to provide torque to the drivetrain.

It is contemplated that an electronically controlled AMT with a sufficiently sized auxiliary flywheel device will achieve the torque filling discussed herein and the additional energy efficiency benefits associated with hybrid arrangements. For similar vehicle and engine operating conditions, this will reduce fuel consumption by around 20% compared to using a dual clutch transmission. Also, using an automated manual transmission combined with flywheel torque fill is no more expensive than using a dual clutch transmission.

The flywheel and associated transmission and coupling (if required) can be retrofitted to existing automated manual transmissions, thereby improving their efficiency and providing improved user comfort during shifting events in a simple and relatively low-cost manner Spend. The overall impact of retrofitting the flywheel described here for torque filling purposes in existing systems is very low because doing so does not require major redesign of the system. Thus, the present aspect can potentially be used in existing vehicles as well as in future vehicle designs.

Transmission and equipment configuration options

It should be understood that the choice of transmission type, as well as the choice of equipment wiring or configuration for the flywheel aspects described above, is not limited to what is specifically described or illustrated herein. Rather, any suitable equipment selection and layout may be implemented, depending on the requirements that need to be achieved for a particular vehicle, engine, machine, or other arrangement.

The function of the transmission device is to match the speed of the flywheel to the speed of the mechanical coupling point where the flywheel is coupled to the output of the ICE or other output device. Effectively, the transmission is a power converter. That is, power in the flywheel embodiments described above is proportional to angular velocity times torque. The function of the transmission or other power converter used is to convert high torque and low speed on one side of it to low torque and high speed on the other side of the power converter.

Both the choice of mechanical coupling point and the transmission design have an impact on the functionality of the flywheel assisted system according to the aspects described herein. Transmission choices in those areas where transmissions are used include belt continuously variable transmission (CVT), traction CVT, mechanical split path infinitely variable transmission (IVT), electric split path IVT, hydrostatic CVT/IVT and one or Multiple motors. Of course, the system is even air-driven.

Figure 9a shows a possible flywheel and transmission layout that could be used for torque filling purposes, for example. Preferably, the flywheel 90 is arranged in a vacuum 92 . Flywheel 90 is connected to coupling clutch 94 by any suitable coupling means. A coupling clutch 94 provides a connection between flywheel 90 and transmission device 96 . The transmission device 96 is in turn mechanically coupled to the transmission input of the vehicle between the internal combustion engine 97 and the transmission 99 .

Figure 9b shows an alternative layout including a split path IVT. Again, preferably, the flywheel 90 is provided in a vacuum 92 and is connected to a coupling clutch 94 which in turn is connected to the transmission. The transmission arrangement used in this arrangement includes an epicyclic stage 96 and an in-line traction transmission 98 . By including an IVT transmission system, the potential functionality of the flywheel assisted engine is improved, providing increased recuperation range at low speeds and enabling acceleration from a standstill.

It can be seen that, unlike the arrangement shown in FIG. 9a where the transmission device is mechanically coupled to the output of the ICE 97, in FIG. 9b the transmission device is coupled at the output of the transmission 99. As mentioned above, this choice of mechanical coupling point can affect the functionality and associated advantages of the flywheel assisted system.

Figures 10a-10b further illustrate potential coupling configuration options for flywheel assistance in accordance with the presently described aspects.

In FIG. 10a, the auxiliary flywheel device 100 is coupled to the ICE 102, upstream of the primary vehicle clutch 104 and the transmission 106. This coupling configuration provides an advantage in that the ratio range required on the transmission device between ICE 102 and flywheel 100 is relatively narrow in order to match the flywheel speed to the speed at its coupling point with ICE 102. That is, because the engine spins at a higher speed relative to the wheels, the ratio difference between the flywheel and the engine is smaller than the ratio difference between the flywheel and the wheels. In addition, the large, powerful gears needed to transition between the flywheel and the ICE are already present in the transmission, but not lower downstream.

The arrangement in Figure 10a further reduces transmission torque by using the transmission's torque advantage. However, because the flywheel is coupled upstream of the clutch 104 , the clutch 104 must be closed to recover and reuse energy from the flywheel 100 in the vehicle driveline 108 . Therefore, energy recovery from the flywheel 100 can be interrupted by the shifting. Furthermore, in this arrangement a powershift transmission is required in order to achieve continuous drive and regenerative braking using the flywheel device 100 for mechanical energy storage.

FIG. 10 b shows an alternative coupling arrangement similar to that shown in FIG. 9 a , in which the flywheel 100 is coupled to the transmission input between the clutch 104 and the transmission 106 . Like the arrangement in Figure 10a, the configuration in 10b provides improved usable range because of the compatible variator ratios between the ICE 102 and the flywheel 100. And, it also achieves a reduction in gearbox torque. However, decoupling is still required during shifting in order to recover and/or reuse energy from flywheel 100 during shifting operations.

Fig. 10c shows another possible coupling arrangement in which the flywheel 100 is coupled at the transmission output. This arrangement is beneficial because energy recovery from flywheel 100 is not interrupted by shifting. Additionally, a flywheel-only mode is possible where the flywheel 100 is the only source of energy and the energy does not come from the ICE 102, which is possible as long as the master clutch 104 is open. However, the configuration in Fig. 10c reduces the overall operating range compared to the configurations of Figs. 10a and 10b, and it also requires increased coupling torque at the transmission output.

Figure 1Od shows a rear axle system in which a flywheel 100 is provided between the engine 102 and the rear wheels 109 of the vehicle. As with the arrangement shown in Figure 10c, this configuration is beneficial because energy recovery from the flywheel is not interrupted by gear shifting, and a freewheel-only mode is possible as long as the master clutch is open. Additionally, flywheel 100 may be used for four-wheel drive assistance or part-time four-wheel drive functions. Thus, the flywheel 100 can assist in diversifying the suitability of the vehicle for different driving conditions. However, like the configuration shown in Fig. 10c, the configuration in Fig. 10d reduces the overall operating range and requires increased coupling torque at the transmission output compared to the configurations shown in Figs. 10a and 10b.

A further use of the flywheel in a suitable configuration as discussed above is in launch support. Depending on the vehicle type and engine load map, the flywheel may be the only torque supply for launch, or it may be used in conjunction with the engine torque supply. For example, for a relatively small vehicle such as in a traffic queue situation, creeping at regular intervals, the flywheel is sufficient to provide torque for the vehicle to break away for each creep. Alternatively, for longer distances or higher speed movement in larger vehicles or smaller vehicles, the flywheel can be used with a fraction of the engine's capacity, for example using two of the engine's 4 available cylinders. An appropriate control strategy can be implemented such that at any given moment the optimum combination of flywheel and engine torque supplies is used, taking into account vehicle factors and potential environmental factors (eg, emission restrictions in a particular region).

Another factor in the suitability of a particular transmission and coupling configuration in accordance with the presently described aspects is the speed of the flywheel itself during operation. At any given moment, the kinetic energy stored within the flywheel is directly proportional to the square of its velocity (Eαω ² ). So, for example, if half of the stored energy is extracted from the high speed flywheel, this will result in a smaller percentage drop in the speed of the high speed flywheel than if half the energy is taken from the low speed flywheel. As a result, a faster flywheel helps reduce the required ratio range for the transmission device coupling the flywheel to the ICE.

transform

It is to be understood that the flywheel aspects described herein are not mutually exclusive, but may be implemented in any suitable combination in a vehicle, machine or other device. For example, an engine layout may include a relatively small flywheel for any or all of the following: driving a supercharger, charging a chemical battery, and providing auxiliary energy supply or recovery during vehicle start or stop events The supply or recovery of auxiliary energy other than that provided by the main power source. The same engine configuration can also include a relatively large flywheel for direct and/or hybrid drive to the vehicle tires.

As with any of the above aspects, it is possible to configure the flywheel so that when the vehicle or equipment is turned off, the flywheel stops and in doing so charges the chemical or other long term battery storage.

Depending on the specific requirements to be met or constraints to be adhered to, flywheels can be included in an engine or machine during manufacture, or, in a variety of different configurations, can be retrofitted to an existing engine or machine after manufacture.

Accordingly, various aspects are provided herein, in each of which a flywheel is implemented in an engine, vehicle, machine or device to advantageously use the energy available therein and to use it to improve overall performance and output. No additional energy source is required to run or charge the flywheel, but instead, it has been recognized that, according to the present aspect, appropriate flywheel arrangements can be used to beneficially capture, store and reuse energy dissipated in conventional systems. Furthermore, the flywheel arrangement herein can be properly operated and controlled to meet time-varying operating conditions and user demands in a straightforward and energy-efficient manner.

In practice, the operation of other devices with which the flywheel cooperates with the flywheel according to the above aspects can be run and controlled by means of appropriate hardware or software. Instructions for controlling operations may be recorded on a digital or analog record carrier or computer readable medium. The record carrier may comprise an optical storage device, such as an optical disc, or may be in the form of a signal, such as a focused laser beam. A magnetic record carrier such as a computer hard drive may also be used for storage of instructions to control the flywheel arrangement described herein. Alternatively, solid state storage or any suitable signal storage may be employed.

A computer or other suitable processing means, such as an engine control unit (ECU), may be programmed to execute instructions for controlling the operation of the described arrangements. The processing means may also be used to control the operation of other elements within an engine, machine vehicle or device in which the flywheel arrangement is incorporated or to which the flywheel arrangement is associated. The processing means may also be used to record and/or store data associated with the flywheel arrangement and/or other elements.

A computer program for use in an ECU or other processing means may be provided to effectuate control of the arrangements described herein. Such a computer implementation could be used to provide automatic control of the flywheel arrangement. Alternatively or in addition, operation or control of the arrangements described herein may be performed using any suitable combination of computer and user-implemented steps. Thus, in operation, a degree of automation may be provided to control the operation of the flywheel arrangement, but options may also be provided to the user (eg, the driver of the vehicle) to issue commands or perform other actions to control the operation of the flywheel arrangement described herein. The control operation of the flywheel arrangement.

The present aspect recognizes that in a vehicle or machine, energy is usually recovered as kinetic energy, and thus, by using a flywheel to store energy in kinetic form, energy loss due to the energy conversion phase is reduced or avoided. Flywheels can store energy in kinetic form for extended periods of time, and furthermore, depending on conditions over time (eg, during engine shutdown), flywheels can be used to provide energy in kinetic form or otherwise to other energy storage devices.

The flywheel aspects described herein provide substantial advantages over existing arrangements by achieving enhanced efficiency and performance in a user-friendly, cost-effective, compact and environmentally friendly manner. They may be implemented in any suitable vehicle, engine, machine or device to enhance its output performance and meet user needs in a manner not previously possible using prior art arrangements.

Claims (36)

CLAIMS 1. An energy storage device (10) comprising a flywheel (12) having at least one input (18) arranged to, in use, The flywheel (12) provides energy, wherein the energy is recovered from engine exhaust. 2. An energy storage device (10) according to claim 1, further comprising exhaust gas recovery means arranged, in use, to direct exhaust gas output from the engine towards the flywheel (12). 3. The energy storage device (10) of claim 2, wherein the exhaust gas recovery device comprises a Tesla turbine. 4. The energy storage device (10) according to claim 2, wherein the exhaust gas recovery device comprises a turbocharger. 5. The energy storage device (10) of claim 4, wherein the turbocharger is a variable geometry turbocharger (VGT). 6. The energy storage device (10) according to any one of claims 1 to 5, further comprising a clutch (16) in the energy path between the exhaust gas recovery device and the flywheel (12) . 7. The energy storage device (10) according to any one of claims 1 to 6, further comprising an output for directing recovered excess exhaust gas energy away from the flywheel (12). 8. The energy storage device (10) according to any one of claims 1 to 7, further comprising a controller for controlling the energy flow through the energy storage device. 9. The energy storage device (10) according to any one of claims 1 to 8, wherein the flywheel is mechanically connected to a variable ratio system (22). 10. The energy storage device (10) of any one of claims 1 to 9, wherein an output of the flywheel (12) is mechanically coupled to an output of an engine to provide an input to a vehicle, machine or the mixing energy of the device. 11. The energy storage device (10) of claim 10, wherein the engine to which the flywheel (12) is mechanically coupled is further arranged to, in use, output exhaust gas for use as input to the Describe the energy of flywheel (12). 12. The energy storage device (10) according to any one of claims 1 to 11, wherein the flywheel (12) is operable for a vehicle, engine, Mechanical battery power for one or more devices in a machine or installation. 13. A vehicle, engine, machine or device comprising an energy storage device (10) according to any one of claims 1 to 12. 14. A method for energy recovery comprising: The energy present in the engine exhaust is harvested, said energy is directed to said flywheel (12) device, and said energy is stored in said flywheel (12) for future use. 15. The method according to claim 14, further comprising the step of providing energy from the flywheel (12) to one or more of an engine, vehicle, machine or device equipped with the flywheel (10) . 16. A method of controlling energy flow through an energy storage device (10), the method comprising: recovering exhaust energy from an exhaust flow, providing said exhaust energy to a flywheel (12); and, outputting said exhaust energy in accordance with dynamic operating conditions Energy stored in said flywheel (12). 17. The method of claim 16, further comprising directing excess exhaust energy away from the flywheel. 18. A method as claimed in claim 16 or 17, further comprising repeating, in use, the step of providing exhaust gas energy to the flywheel as required for charging the flywheel. 19. Apparatus comprising a charge boost device which, in use, provides inlet boost to an engine, the apparatus further comprising: a flywheel, wherein the flywheel is arranged to provide energy to drive the The operation of the inflation booster device is described. 20. The apparatus of claim 19, wherein the charge boosting device is a supercharger. 21. The apparatus of claim 19, wherein the charge boosting device is a turbocharger. 22. Apparatus according to any one of claims 19 to 21, further comprising an input arranged to supply energy to the flywheel in use. 23. Apparatus according to claim 22, wherein the input is arranged to direct energy recovered from any of the following: a vehicle power train, engine exhaust, mechanical equipment, a chemical battery or an electric motor, and The recovered energy is supplied to the flywheel. 24. The device of any one of claims 19 to 23, further comprising a controller for controlling energy flow through the device. 25. The apparatus of claim 19, wherein the charge boosting device is a turbocharger including a wastegate, and wherein the flywheel is disposed on the turbocharger in the wastegate ring, such that the flywheel is arranged to both provide energy to drive the turbocharger and to store energy recovered from gases exhausted by the turbocharger's wastegate. 26. Apparatus according to any one of claims 19 to 25, wherein the charge boost device is further arranged to receive an energy input from the engine, wherein the charge boost device provides a boost input to in the engine. 27. A vehicle, engine or machine comprising a device as claimed in any one of claims 19 to 26. 28. A method for increasing engine power comprising utilizing a flywheel to provide energy to drive operation of a charge boosting device, and operating said charge boosting device to increase inlet charge pressure in said engine. 29. The method of claim 28, further comprising the step of supplying energy to the flywheel using existing energy sources within a vehicle or machine in which the engine is provided. 30. A method for controlling inlet air pressure in an engine, comprising: operating a charge boost device to increase said inlet air pressure above atmospheric pressure, and further comprising using a flywheel to provide energy to drive said charge boost device operation wherein the amount of energy supplied by the flywheel is controlled to provide optimum boost depending on instantaneous engine operating conditions. 31. A processing device programmed and operable to execute instructions for carrying out the method according to any one of claims 14-18 or 28-30. 32. An engine control unit (ECU) comprising the processing means of claim 31. 33. A record carrier having stored thereon instructions which are executed by processing means in order to carry out the method according to any one of claims 14-18 or 28-30. 34. A record carrier as claimed in claim 33, wherein the record carrier comprises an optical, magnetic or solid state storage device or a readable signal. 35. A computer program comprising instructions executable by processing means to carry out the method according to any one of claims 14-18 or 28-30. 36. An apparatus, method or control scheme substantially as herein described or as illustrated in the accompanying drawings.

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