Description:FIELD OF THE INVENTION
[0001] The present subject matter is related, in general to a vehicle, and more particularly, but not exclusively to an electrical machine for the vehicle.
BACKGROUND OF THE INVENTION
[0002] Vehicles operative on principles of conservation of electrical energy or 5 even in a hybrid power transmission system, the torque delivery of the prime mover plays a dire role. Electrical machines such as motors and generators are operative as prime movers for the electric driven vehicles or vehicles employing hybrid technology. Electric motors are machines which transform the electrical energy received from energy storage devices into mechanical energy to achieve 10 vehicle propulsion. The electric motor is based on principles of electromagnetic interactions of magnetic fields in a housing.
[0003] Conventional configuration of electric machines comprises a rotor and a stator. The electric motor operates through interaction between a magnetic field and electric current in a winding to generate an acting force in the form of torque 15 as an output of the electric machine’s output shaft. The rotor is the rotating components of the electrical machine while the stator is the stationary component of the electrical machine. The stator component comprises a core and winding. The stator carries the rotating magnetic field which is induced by a power supply. The rotor is typically disposed inside the core of the stator and comprises a core 20 and rotor windings powered by a DC supply. The rotor may additionally be provided with slip rings and slots, and the rotor comprises an output shaft. The electromagnetic force owing to the configuration of the stator causes rotation of the rotor in view of electromagnetic induction. The electromagnetic induction is a phenomenon in which electromotive force (also referred to as emf) is induced in a 25 current carrying conductor because of a variable magnetic field.
[0004] Conventionally, the electric machines such as motors employed for electric vehicles have a radial flux distribution. In a radial flux layout of the electrical machine, the rotor and stator have an air gap between them with the magnetic field of the stator being perpendicular to the shaft of the rotor. The motor in radial 30
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flux type, have the stator designed around the rotor such that the magnetic field generated by the stator windings travel radially across the air gap between the stator and rotor. The magnetic field of the stator induces torque via emf to make the rotor turn. The typical topology consists of a cylindrical rotor spinning inside a cylindrical stator. The electromagnetic flux first circulates radially outward from
5 the rotor to the stator and then circumferentially along the stator from one stator tooth to another, and then return radially inward from the stator to the rotor to close the flux loop. The design of the radial flux motor is typically large and bulky which adversely affects the power to weight ratio of an electric vehicle. [0005] In order to satiate the torque requirements and the power densities required
10 in present demands of the electric vehicles, a different configuration of electric machines is required. The electric machines having an axial flux distribution. In axial-flux motors, the magnetic field is parallel to the rotor shaft and the rotor windings are arranged in a planar fashion. The design of the axial flux motor, despite providing a more compact motor design with reduced axial length, has 15 pertinent issues of magnetic flux leakages between the rotor and stator assembly. The magnetic field flows parallel to the rotor shaft. The axial flux motor provides an improved power to weight ratio for the vehicle.
[0006] While an axial flux distribution provides improved torque delivery and power density over radial flux distribution machines, the same may not satisfy the 20 ever-growing performance demands of the mobility solutions. Therefore, there arises a need in the automotive industry to further improve on the performance of electric machines based on axial flux distribution. Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of described systems with some aspects 25 of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.
SUMMARY
[0007] According to embodiments illustrated herein, the present subject matter relates to an electrical machine comprising a stator member and one or more rotor 30
members. The stator member comprises one or more portions. The one or more rotor members are communicatively coupled to the one or more portions of the stator member. The one or more portions of the stator member are selectively operated to associatively operate the one or more rotor members.
[0008] According to embodiments illustrated herein, the present subject matter
5 provides a vehicle comprising an input energy source and an electrical machine. The input energy source is operatively coupled to an electrical machine. The electrical machine comprises a stator member and one or more rotor members. The stator member comprises one or more portions. The one or more rotor members are communicatively coupled to the one or more portions of the stator 10 member. The input energy source is configured to selectively operate the one or more portions of the stator member.
[0009] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent 15 by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[00010] The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present 20 invention.
[00011] Figure 1 illustrates a block diagram of a vehicle in accordance with some embodiments of the present disclosure.
[00012] Figure 2 illustrates an electrical machine in accordance with some other embodiments of the present disclosure. 25
DETAILED DESCRIPTION OF THE DRAWINGS [00013] The present disclosure may be best understood with reference to the detailed figures and description set forth herein. Various embodiments are discussed below with reference to the figures. However, those skilled in the art 4
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will readily appreciate that the detailed descriptions given herein with respect to the figures are simply for explanatory purposes as the system may extend beyond the described embodiments. For example, the teachings presented, and the needs of a particular application may yield multiple alternative and suitable approaches to implement the functionality of any detail described herein. Therefore, any
5 approach may extend beyond the particular implementation choices in the following embodiments described and shown. [00014] References to “one embodiment,” “at least one embodiment,” “an embodiment,” “one example,” “an example,” “for example,” and so on indicate that the embodiment(s) or example(s) may include a particular feature, structure,
10 characteristic, property, element, or limitation but that not every embodiment or example necessarily includes that particular feature, structure, characteristic, property, element, or limitation. Further, repeated use of the phrase “in an embodiment” does not necessarily refer to the same embodiment.
[00015] The present invention now will be described more fully hereinafter with 15 different embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather those embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the invention to those skilled in the art. 20
[00016] The present invention is illustrated with an electrical machine. However, a person skilled in the art would appreciate that the present invention is not limited to the present illustration and certain features, aspects and advantages of embodiments of the present invention can be used with a variety of vehicular equipment and mobility solutions to include but not be limited to two wheeled, 25 three wheeled vehicle or multi-axle vehicles in the automotive industry.
[00017] It is an objective of the present subject matter to provide an electrical machine of compact design with improved life cycle in high power applications.
[00018] It is an object of the present subject matter to provide an enhanced electrical machine accommodating modularity in vehicle transmission systems pertinent to desired torque, throttle and riding mode requirements.
[00019] It is objective of the present subject matter to address issues of magnetic flux leakages otherwise pertinent in conventional arts which raise issues of 5 efficiency in the electrical machine.
[00020] The present subject matter along with all the accompanying embodiments and their other advantages would be described in greater detail in conjunction with the figures in the following paragraphs.
[00021] The present subject matter is further described with reference to 10 accompanying figures. It should be noted that the description and figures merely illustrate principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific 15 examples thereof, are intended to encompass equivalents thereof.
[00022] The present subject matter may be implemented in any form of automobile. However, for the purpose of explanation and by no limitation, the present invention, and corresponding additional advantages and features are described through the following embodiments depicting a two wheeled vehicle. 20
[00023] Figure 1 illustrates a block diagram of a vehicle in accordance with some embodiments of the present disclosure.
[00024] With reference to Figure 1, 100 denotes a vehicle, 102 denotes a control unit, 104 denotes an input energy source, 200 denotes an electrical machine, 202 denotes a stator member, and 204 denotes one or more rotor members. 25
[00025] In an aspect, the vehicle 100 comprises a control unit 102, an input energy source 104 and an electrical machine 200. The control unit 102 is communicatively coupled to the input energy source 104. The electrical machine 200 is operatively coupled to the input energy source 104. 6
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[00026] In an aspect, the electrical machine 200 comprises a stator member 202 and one or more rotor members 204. The stator member 202 comprises one or more portions. The one or more rotor members 204 are communicatively coupled to the one or more portions of the stator member 202. The input energy source is configured to selectively operate the one or more portions of the stator member
5 202.
[00027] In an aspect, the one or more portions of the stator member 202 comprises at least a first portion and a second portion being separated by an insulating layer. The input energy source 104 is configured to selectively operate the first portion and the second portion of the stator member 202. The first portion 10 of stator member 202 is communicatively coupled to a first rotor member 204 of the one or more rotor members 204 and the second portion of the stator member 202 is communicatively coupled to a second rotor member 204 of the one or more rotor members 204. The selective operation of the one or more portions are configured to alternately operate the first rotor member 204 and the second rotor 15 member 204 at an associated operation range.
[00028] In an aspect, the one or more rotor members 204 are connected to one or more output shafts 206 of a transmission system of the vehicle 100. Each of the one or more rotor members 204 are configured to operate at a pre-defined range of operation. 20
[00029] In an aspect, the control unit 102 comprises a look-up table comprising one or more vehicle parameters associated with an output energy of the input energy source 104 to selectively operate the one or more portions of the stator member 202. The one or more vehicle parameters comprising at least a torque assist input, a throttle input and a riding mode input. 25
[00030] In an aspect, based on the received one or more vehicle parameters the control unit 102 is configured to fetch the associated output energy and transmit a signal linked to the output energy of the input energy source 104.
[00031] For instance, when the throttle angle or rate of change of throttle by the user of the vehicle 100 is below a pre-set threshold, the control unit 104 is configured to selectively energize the first portion of the stator member 202 which would associatively induce electromotive force on the first rotor member 204 which operates the output shaft 206 a first predefined range. Alternately, when the
5 throttle angle or rate of change of throttle by the user of the vehicle 100 is above the pre-set threshold, the second portion of the stator member 202 is energized by the input energy source 104. The second portion of the stator member 202 being operatively coupled to the second rotor member 204 leads to the induced electromotive force operating the output shaft 206 at a second predefined range. 10
[00032] In an embodiment, the first rotor member 204 is configured to operate at a first pre-defined range of 0 to 2500 rpm, and the second rotor member 204 being configured to operate at a second pre-defined range of 2500 to 12500 rpm.
[00033] Figure 2 illustrates an electrical machine in accordance with some other embodiments of the present disclosure. 15
[00034] With reference to Figure 2, 202 denotes a stator member, 204 denotes one or more rotor members, 202a denotes a stator core, 202b denotes a first portion and second portion of stator winding, 204b denotes one or more rotor windings, 204a denotes a rotor core, 204c denotes a power supply to the one or more rotor members, and 206 denotes an output shaft of the electrical machine. 20
[00035] In an aspect, the electrical machine 200 comprises a stator member 202 and one or more rotor members 204. The stator member 202 comprises one or more portions. The one or more rotor members are communicatively coupled to the one or more portions of the stator member 202. The one or more portions of the stator member 202 are selectively operated to associatively operate the one or 25
more rotor members 204. [00036] In an aspect, the one or more portions of the stator member 202 comprising at least a first portion and a second portion being separated by an insulating layer. The input energy source 104 is configured to selectively operate 8
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the first portion and the second portion of the stator member 202. In another aspect, the input energy source 104 is at least one of a six phase inverter and a three phase inverter. [00037] In an aspect, the first portion of the stator member 202 is communicatively coupled to a first rotor member 204 of the one or more rotor
5 members 204. The second portion of the stator member 202 IS communicatively coupled to a second rotor member 204 of the one or more rotor members 204.
[00038] In an aspect, the first portion of the stator member 202 is communicatively coupled to a first rotor member 204 of the one or more rotor members 204. The second portion of the stator member 202 is communicatively 10 coupled to a second rotor member 204 of the one or more rotor members 204.
[00039] In an aspect, the first rotor member 204 is configured to operate at a first pre-defined range of 0 to 2500 rpm, and the second rotor member 204 is configured to operate at a second pre-defined range of 2500rpm to 12500 rpm.
[00040] In an aspect, the one or more rotor members 204 comprising a steel core 15 204a with surface mounted magnetic poles 204b placed between a field winding 202b and one or more output shafts 206. In another aspect, the rotor member 204 has a permanent magnet arranged in a pole-slot configuration. In an embodiment, the rotor member has got steel core and surface mounted poles which are permanent magnet (PM) type and iron type. The output shaft 206 and a magnetic 20 tube placed between DC field winding and the output shaft 206. The rotor PM poles are North-South (NS) type. Some space between PM and iron poles is considered for reducing the flux leakage.
[00041] In an aspect, the stator member 202 comprising one or more portions may alternately be referred to a split stator assembly. In an aspect, the insulating layer 25 or insulating material such as but not limited to an air gap separates the magnetic fluxes on either side of the stator-rotor combination such that no electromotive force gets permeated between the first portion and second portion of the stator member 202. In another aspect the insulating layer acts as a partition between
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each split or portion of the stator member 202. The partition is made as an assembly mounted one such that the magnetic field at each side (towards the first rotor member and the second rotor member) are not impacted. [00042] In an embodiment, the first rotor member and the second rotor member of the one or more rotor members 204 of the electrical machine 200 are mounted on
5 separate output shafts 206. Therefore, the first output shaft 206 associated with the first rotor member 204 operates at a first pre-defined range, while the second output shaft 206 associated with the second rotor member 204 operates at a second predefined range. In an aspect, the first rotor member and the second rotor member are selectively energized by the split stator assembly comprising a first 10 portion and a second portion.
[00043] In an embodiment, the stator member 202 is a split stator with mountable assembly and having a thin insulating material or layer of magnetic field such that when the stator coils are energized each of the one or more rotor members 204 will not get drifted due to the magnetic flux. As there will be at least two rotors 15 each rotor can be excited based on the speed requested. First rotor member can be excited for speeds up 0 to 2500rpm and second rotor member can be excited for speeds up from 2500 to 12500 rpm based on which the stator coil winding can be decided and done.
[00044] In an aspect, based upon the torque demand and the position of the split 20 stator any one side of the stator coils will be excited such that permanent magnets mounted on the rotor member will rotate at the demanded speed. Similarly, each portion of the split stator member 202 will be excited based on the configuration chosen and based upon the demand from throttle.
[00045] In a preferred embodiment, the electrical machine 200 may be described 25 to comprise of a single spilt stator member with two rotor members 204 mounted on two difference output shafts 206, with the input energy source 104 being a six phase inverter. The one or more rotor members 204 comprise an appropriate pole slot combination, with the stator member 202 and the one or more rotor members 204 enclosed in a single casing. In another embodiment, the disclosed 30
configuration of the electrical machine 200 may be applicable to a switched reluctance motor. [00046] In conventional axial flux motor, typically the configuration comprises a dual rotor and a single stator which provides a high torque and low volume. While this structure is suitable for application in electric vehicles, the overall life cycle
5 of the motor deteriorates since the same shaft output is subjected to a multitude of torque ranges. The present configuration of a stator member 202 with a first portion and a second portion, in other terms with a split assembly, provides selective energization of the one or more rotor members 204, therefore limiting the range of operation against potential fatigue stresses. The present subject matter 10 therefore increases the overall durability of the designed electrical machine.
[00047] Additionally, the configuration of the rotor member with a steel core and the surface being mounted with magnetic poles of iron type or permanent magnet type placed at optimized distance to each other in the magnetic field of the stator 202 reduces the magnetic flux leakage which is a concern in conventional motor 15 designs.
[00048] The present disclosure of the stator member 202 with one or more rotor members 204 regulates the magnetic harmonics between either side of the stator member 202 on either output shafts 206.
[00049] The present subject matter achieves a wider operational range of the rotor 20 members 204 between 0 rpm to 12500 rpm effectively since the ranges of operation are well distributed between the one or more rotor members 204. In another aspect, the present subject matter can achieve a multitude of operational ranges by having more than two portions in the stator member which may be selectively energized and can consequently operate the rotor member with greater 25
precision in torque delivery at the output shafts 206. Therefore, the present subject matter provides more robust speed and torque control. [00050] In an embodiment, the selective energization of the stator member in the first portion may be operative when the vehicle 100 is in an economy mode of 11
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operation while the second portion may be energized when the vehicle 100 is in a sport mode of operation. [00051] In light of the above-mentioned advantages and the technical advancements provided by the disclosed structure, the claimed vehicle and structure as discussed above are not routine, conventional, or well understood in
5 the art, as the claimed system enable the following solutions to the existing problems in conventional technologies. Further, the claimed system clearly brings an improvement in the protection of the vehicle components as well as the frame assembly against sudden external impacts as the claimed structure and vehicle and constructional features provide a technical solution to a technical problem. 10
[00052] Finally, the language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter, and is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based here on. Accordingly, 15 the embodiments of the present invention are intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.
[00053] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. A person with ordinary skills in the art will appreciate that the systems, modules, and sub-20 modules have been illustrated and explained to serve as examples and should not be considered limiting in any manner. It will be further appreciated that the variants of the above disclosed system elements, modules, and other features and functions, or alternatives thereof, may be combined to create other different systems or applications. Those skilled in the art will appreciate that any of the 25 aforementioned system modules may be suitably replaced, reordered, or removed, and additional steps and/or system modules may be inserted, depending on the needs of a particular application.
[00054] While the present disclosure has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes 30
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may be made and equivalents may be substituted without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its scope. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed, but that the
5 present disclosure will include all embodiments falling within the scope of the appended claims. , Claims:We Claim:
1.An electrical machine (200), the electrical machine (200) comprising:
a stator member (202), the stator member (202) comprising one or more portions; and
one or more rotor members (204), the one or more rotor members 5 (204)being communicatively coupled to the one or more portions of thestator member (202),
wherein the one or more portions of the stator member (202)being selectively operated to associatively operate the one ormore rotor members (204).10
2.The electrical machine (200) as claimed in claim 1, wherein the one ormore portions of the stator member (202) comprising at least a first portionand a second portion being separated by an insulating layer,
wherein an input energy source (104) being configured to 15 selectively operate the first portion and the second portion of the stator member (202), and
wherein the input energy source (104) being at least one of a six phase inverter and a three-phase inverter.
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3.The electrical machine (200) as claimed in claim 2, wherein the firstportion of the stator member (202) being communicatively coupled to afirst rotor member (204) of the one or more rotor members (204); andwherein the second portion of the stator member (202) beingcommunicatively coupled to a second rotor member (204) of the one or25 more rotor members (204).
4.The electrical machine (200) as claimed in claim 3, wherein the first rotormember (204) being configured to operate at a first pre-defined range of 0
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to 2500 rpm, and wherein the second rotor member (204) being configured to operate at a second pre-defined range of 2500rpm to 12500 rpm.
5.The electrical machine (200) as claimed in claim 1, wherein the one ormore rotor members (204) comprising a steel core (204a) with surface5 mounted magnetic poles (204b) placed between a field winding (202b) anda shaft (206).
6.A vehicle (100), the vehicle (100) comprising:
an input energy source (104), the input energy source (104) being 10 operatively coupled to an electrical machine (200),
wherein the electrical machine (200) comprising:
a stator member (202), the stator member (202) comprising one or more portions, and
one or more rotor members (204), the one or more 15 rotor members (204) being communicatively coupled to the one or more portions of the stator member (202),
wherein the input energy source (104) being configured to selectively operate the one or more portions of the stator member (202). 20
7.The vehicle (200) as claimed in claim 6, wherein one or more portions ofthe stator member (202) comprising at least a first portion and a secondportion being separated by an insulating layer,
wherein an input energy source (104) being configured to 25 selectively operate the first portion and the second portion of the stator member (202),
wherein the first portion of stator member (202) being communicatively coupled to a first rotor member (204) of the one or more rotor members (204) and the second portion of the stator member (202) 30
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being communicatively coupled to a second rotor member (204) of the one or more rotor members (204),
wherein the selective operation of the one or more portions being configured to alternately operate the first rotor member (204) and the second rotor member (204) at an associated operation range. 5
8.The vehicle (100) as claimed in claim 6, wherein the one or more rotormembers (204) being connected to one or more output shafts (206) of atransmission system of the vehicle (100), wherein each of the one or morerotor members (204) being configured to operate at a pre-defined range of10 operation.
9.The vehicle (100) as claimed in claim 6, wherein the input energy source(104)being coupled to a control unit (102),
wherein the control unit (102) comprising a look-up table; and 15
wherein the look-up table comprising one or more vehicle parameters associated with an output energy of the input energy source (104)to selectively operate the one or more portions of the stator member(202).
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10.The vehicle (100) as claimed in claim 9, wherein the one or more vehicleparameters comprising at least a torque assist input, a throttle input, ariding mode input,
wherein based on the received one or more vehicle parameters the control unit (102) being configured to fetch the associated output 25 energy and transmit a signal linked to the output energy of the input energy source (104).