Claims:STATEMENT OF CLAIMS
We claim:
1. A multiple voltage level hybrid system (100) for a vehicle for providing propulsive power to the vehicle at any given time, wherein the system (100) comprises a
a first power source (PS1) (10) and a second power source (PS2) (20, 21, 22), wherein the PS1 (10) and the PS2 (20, 21, 22) are tightly coupled and drive one of a first axle (72) of the vehicle; and
a third power source (PS3) (31, 32, 33, 34, 35) mounted on a second axle (71) of the vehicle.
2. The system, as claimed in claim 1, wherein the PS1 (10) and the PS2 (20, 21, 22) are connected using at least one of a belt drive/ chain drive system (41); a direct positive gear (42); and a decoupling mechanism (62).
3. The system, as claimed in claim 1, wherein the PS2 (20, 21, 22) and the PS3 (31, 32, 33, 34, 35) operate at the separate voltage levels.
4. The system, as claimed in claim 1, wherein the PS2 (20, 21, 22) and the PS3 (31, 32, 33, 34, 35) operate at the same voltage level.
5. The system, as claimed in claim 1, wherein the PS2 (20, 21, 22) and the PS3 (31, 32, 33, 34, 35) are connected using a power conversion device (80), wherein the power conversion device (80) is at least one of an insulator; and a converter.
6. The system, as claimed in claim 1, wherein the system (100) is configured for turning off the PS1 (10), when the vehicle is at least one of moving; and operating at a low load point.
7. The system, as claimed in claim 1, wherein the system (100) is configured for using at least one of the PS2 (20, 21, 22) and the PS3 (31, 32, 33, 34, 35) to recover energy, when the vehicle is decelerating.
8. The system, as claimed in claim 1, wherein the PS2 (20, 21, 22) functions as the vehicle generator/starter system and provides power to a starting device of the vehicle and a vehicle auxiliary electrical load supply.
9. The system, as claimed in claim 1, wherein the PS1 (10) and the PS2 (20, 21, 22) are connected to the first axle (72) using a decoupling device (60) and a torque multiplier device (50).
10. The system, as claimed in claim 1, wherein the PS3 (31, 32, 33, 34, 35) is connected to the second axle (71) using a decoupling device (60) and a torque multiplier device (50).
11. The system, as claimed in claim 1, wherein the PS3 (31, 32, 33, 34, 35) is mounted directly on the second axle (71).
12. The system, as claimed in claim 1, wherein the PS3 (31, 32, 33, 34, 35) is mounted directly on wheels (103, 104) connected to the second axle (71).
13. The system, as claimed in claim 1, wherein the system (100) is configured for using at least one of the PS1 (10), the PS2 (20, 21, 22), and the PS3 (31, 32, 33, 34, 35) as backup, if energy reserve level of any one of the PS1 (10), the PS2 (20, 21, 22), and the PS3 (31, 32, 33, 34, 35) is low.
14. The system, as claimed in claim 1, wherein the system (100) is configured for operating the PS2 (20, 21, 22), and the PS3 (31, 32, 33, 34, 35) in tandem.
15. The system, as claimed in claim 1, wherein the system (100) is configured for operating the PS2 (20, 21, 22), and the PS3 (31, 32, 33, 34, 35) separately.
, Description:TECHNICAL FIELD
[001] Embodiments herein relate to vehicle systems and more particularly to powertrain systems in vehicles.

BACKGROUND
[002] A conventional vehicle powertrain comprises of an Internal Combustion (IC) engine, a flywheel, a de-coupling mechanism, a driveline including transmission, and a differential and axle system, which drives the wheels of the vehicle. Furthermore, various accessories and feed loads (such as cooling pump, cooling fan, conventional brakes, power steering, and air conditioning systems) are connected to the primary power source (which can be the IC engine).
[003] Hybrid vehicles (available in the market) use a single voltage level for hybridization, with a single machine mounted in a different location in powertrain architecture to provide the alternate propulsion. However this configuration provides limited functionality in the hybrid mode due to the inherent configuration.

OBJECTS
[004] The principal object of embodiments herein is to disclose a multiple voltage level hybrid system for a vehicle which provides propulsive power to the vehicle at any given time, wherein a first power source (such as an Internal Combustion (IC) engine) and a second power source (such as an electric or hydraulic machine) are tightly coupled and drive one of a first axle of the vehicle and a third power source (such as an electric or hydraulic machine) is mounted on the second axle.
[005] Another object of embodiments herein is to disclose a multiple voltage level hybrid system for a vehicle, wherein the first power source (such as an Internal Combustion (IC) engine) and the second power source (such as an electric or hydraulic machine) are tightly coupled using a positive torque transfer device.

BRIEF DESCRIPTION OF FIGURES
[006] This invention is illustrated in the accompanying drawings, through out which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[007] FIG. 1 depicts a hybrid powertrain present in the vehicle, according to embodiments as disclosed herein.

DETAILED DESCRIPTION
[008] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[009] The embodiments herein disclose a multiple voltage level hybrid system for a vehicle which provides propulsive power to the vehicle at any given time, wherein a first power source (such as an Internal Combustion (IC) engine) and a second power source (such as an electric or hydraulic machine) are tightly coupled and drive one of a first axle of the vehicle and a third power source (such as an electric or hydraulic machine) is mounted on the second axle. Referring now to the drawings, and more particularly to FIG. 1, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments.
[0010] Embodiments herein disclose a multiple voltage level hybrid system for a vehicle which provides propulsive power to the vehicle at any given time, wherein a first power source (such as an Internal Combustion (IC) engine) (PS1) and a second power source (such as an electric or hydraulic machine) (PS2) (also referred to herein as a secondary power source) are tightly coupled and drive one of a first axle of the vehicle (which can be either the front axle or the rear axle) and a third power source (such as an electric or hydraulic machine) (PS3) is mounted on the second axle (which can be the front axle or the rear axle). In an embodiment herein, the vehicle can use series hybrid architecture. In an embodiment herein, the vehicle can use parallel hybrid architecture. The vehicle can use at least one power source to provide power to the vehicle. The vehicle can use at least one power source to provide power to the vehicle. The vehicle can use at least one power source to propel the vehicle from zero velocity.
[0011] Both the axles can move independently or in tandem wherein it is possible to drive with at least one the power sources (PS1, PS2 and PS3). PS1 and PS2 are connected using at least one positive torque transfer device such as at least one of feed belt, chain drive, gear, and so on. In an embodiment herein, PS3 can be mounted close to the second axle. PS3 can be decoupled from the second axle and/or the primary power system (which comprises of a combination of PS1 and/or PS2) with a decoupling device, which can be at least one of a clutch and/or a gear. As the drive systems (PS1/PS2 and PS3) have separate voltage levels of operation, the efficiency losses related to voltage conversion can also be avoided.
[0012] Both the primary power source (PS1 and/or PS2) and the secondary power source (PS3) can propel the vehicle in conjunction or separately, along with other conventional vehicle powertrain components, wherein some of the feed loads are being electrified. In an embodiment herein, both power sources (PS2 and PS3) can have the same voltage level, based on the powertrain configuration. In an embodiment herein, both power sources (PS2 and PS3) can have different voltage levels, based on the powertrain configuration. The power sources (PS2 and PS3) can be connected via a power level conversion device such as a converter, insulator, and so on. The power conversion device enables a flexibility to operate both the power sources either in connection or as separate dedicated power sources.
[0013] Embodiments herein enable switching off of PS1 while the vehicle is moving with the help of at least one of PS2 or PS3. This will help in making the vehicle run in zero-emission mode, when the vehicle is moving and the vehicle is operating at a low load point (driver demand low) and hence help in reducing operation of PS1 in low efficiency zone.
[0014] When the vehicle is moving, with PS1 in positive ignition, PS2 can be used as generator to load the engine if the operating points of PS1 are inefficient and the generated energy can be used to charge an energy pack present in the vehicle. The delta energy generated during this operation can be used to operate the vehicle in zero-emission mode (pure electric drive mode). When the vehicle is decelerating, based on the energy pack status and charge acceptance capacity, at least one of PS2 and PS3 can be used to recover energy back, with or without the assistance of PS1. PS2 and PS3 can be operated in conjunction with the brakes of the vehicle or independently based on the deceleration event, while maintaining the same feel to driver.
[0015] FIG. 1 depicts a hybrid powertrain present in the vehicle. The powertrain 100 can comprise of a primary power source (PS1 (10) and PS2 (20, 21, 22)). The primary source (PS1, PS2) can be closely coupled to the wheels (101, 102) to avoid drive transmission related system losses. PS2 can function as the vehicle generator/starter system and can provide power to the starting device and the vehicle auxiliary electrical load supply. Voltage levels for the primary source (PS1, PS2) can vary from ultra low voltage to high voltage depending on vehicle level requirement.
[0016] PS1 (10) can be an IC based engine or any other positive propulsive device. PS1 can be mechanically connected to PS2 (20, 21, 22) using at least one of a belt drive/ chain drive system (41), a direct positive gear (42) or a decoupling mechanism (62). The controller and energy storage module (92) for PS2 (20, 21, 22) is connected to PS2 (20, 21, 22) through energy and communication layers (111, 112, 113). PS1 (10) and PS2 (20, 21, 22) can be connected to an axle (72) of the vehicle. PS1 and PS2 (20, 21, 22) can provide power to the axle (72) to drive the wheels (101, 102) connected to the axle (72) through a decoupling device (60) and a torque multiplier device (50). The primary source can also be used for driving the vehicle with engine off during running in and electrical supply.
[0017] PS3 (31, 32, 33, 34, 35) can be a device that can propel the vehicle with any form of energy and can recover the energy during vehicle declaration. Examples of PS3 (31, 32, 33, 34, 35) can be, but not limited to, electric machines, hydraulic systems, and so on. PS3 (31, 32, 33, 34, 35) can be mechanically connected to at least one axle of the vehicle (71, 72). In an embodiment herein, PS3 (31, 32, 33, 34, 35) can be mechanically connected to one axle of the vehicle (71, or 72). In an embodiment herein, PS3 (31, 32, 33, 34, 35) can be mechanically connected to both axles of the vehicle (71, and 72). In an embodiment herein, PS3 (31, 32, 33, 34, 35) can be connected to the axle (71, 72) using at least one of a torque multiplier system (50), or a decoupling device (61). In an embodiment herein, PS3 (31, 32, 33, 34, 35) can be mounted directly on the axle (71). In an embodiment herein, PS3 (31, 32, 33, 34, 35) can be mounted directly on the wheels (103, 104). The controller and energy storage module (91) for PS3 drive system, can be connected to PS3 (31, 32, 33, 34, 35) using energy and communication layers (121, 122, 123, 124).
[0018] In case energy reserve level of any one of the power sources (PS1, PS2 and PS3) is low, any one of the other power sources can provide backup without affecting the drive behavior of the vehicle.
[0019] The decoupling device (60) can be used to separate the primary power source (PS1 and PS2) from the secondary power source PS3 (31, 32, 33, 34, 35). The power sources (PS2, PS3), in tandem or separately, can provide power to the vehicle during stages such as vehicle launch, acceleration phase, and so on.
[0020] The controller and energy storage modules (91, 92) can be connected using a device (80). In an embodiment herein, the device (80) can be an insulator. In an embodiment herein, the device (80) can be a converter. If the charge/energy level in any of the power sources (PS1, PS2) is low, the device (80) can enable the power sources to share the energy content.
[0021] The power sources (PS1, PS2) can recover vehicle traction energy back from the wheel during vehicle deceleration, based on the level of charge left in the power sources (PS1, PS2) and the respective energy storage system (91, 92) will charge the power sources (PS1, PS2).
[0022] The power sources (PS1, PS2) will ensure that the vehicle drive speed is maintained as per the driver requirement when there is an option to switch off the engine.
[0023] Embodiments herein merely use a vehicle equipped with two axles as an example. It may be obvious to a person of ordinary skill in the art to implement embodiments as disclosed herein for vehicles with any number of axles, wherein each of the axle can have one or more power sources connected to it.
[0024] Embodiments herein enable a more smother, quicker and better operation than the convention vehicle, based on engine start and restart characteristics, with start time as measured parameter.
[0025] Embodiments herein provide a flexibility to use the vehicle in any one of the operational modes at any given point of time and also provide a flexibility to move from one mode to another without driver intervention and without any feedback to the user of the vehicle.
[0026] Embodiments herein disclose a multiple voltage level based propulsion technique for the vehicle such that the vehicle can run with the optimized fueling and hence result in reduction in fuel consumption.
[0027] Embodiments herein disclose an optimized solution to have all possible hybrid modes with lesser system complexity.
[0028] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.