Description:F O R M 2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See section 10; rule 13)

1. TITLE OF THE INVENTION:
WINDING ARRANGEMENT FOR A MOTOR USING ELECTRICALLY CONDUCTIVE FLAT STRIPS
2. APPLICANT:
Name: ADITYA AVARTAN TECHNOLOGIES PRIVATE LIMITED
Nationality: Indian
Address: #180, Bommasandra Industrial Area, Hosur, Road, Bangalore, Karnataka, India, 560099

3. PREAMBLE:
Complete Specification
The following specification particularly describes the invention and the manner in which it is to be performed.

BACKGROUND
Field of Invention
[0001] The subject matter in general relates to a technical field of a winding arrangement in a motor. More particularly but not exclusively, the subject matter relates to winding arrangement of a stator assembly, using electrically conductive flat strips in a switched reluctance motor (SRM).
Discussion of related field
[0002] Conventionally, windings in electric motors are usually provided on stator poles to create electromagnetic fields around the stator poles when current is passed from a power supply through the windings wound around the stator poles. The windings are generally used in motors to provide electromagnetic field thereby converting electrical energy into mechanical energy based on the principle of electromagnetic induction. Different types of windings are implemented in motors based on the dimensions and shape of the motor. Factors like insulation strength, magnetic field capacity, Q-factor and inductance, show effect on the shape of coil windings.
[0003] The stator windings in particular, are conventionally made of wire of circular cross-section of high conductivity copper. These stator windings are arranged in such a manner that the induced electromagnetic fields (emfs) in all the phases of the coils have the same magnitude and frequency. The arrangement of the winding plays a significant role in the elimination of 3rd harmonics from the line emf. Conventional windings with stranded round wires reduce current ratings due to the presence of lengthy end windings thereby providing low fill factors.
[0004] Further, the formerly wound stator windings are difficult to be repaired since it requires the entire stator assembly 100 to be dismantled just to repair a portion of the stator winding. Also, in conventional windings, the stator pole needs to be wider to receive the winding because of the winding configuration thus resulting in increased air gap reluctance and noise.
[0005] In view of the foregoing discussion, there is a need of a winding arrangement that will overcome the foresaid drawbacks of the existing art.

SUMMARY
[0006] An embodiment discloses a winding arrangement for a motor using electrically conductive flat strips. The winding arrangement comprises at least a layer of the flat strip wound around a stator pole. Also, the winding arrangement comprises at least one spacer disposed between adjacent layers of the flat strip wound around each stator pole. The spacer is configured to form a space between the adjacent layers of the flat strip.
BRIEF DESCRIPTION OF DIAGRAMS
[0007] Exemplary embodiments of the present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which,
[0008] FIG. 1A is a perspective view of a stator assembly 100 with winding arrangement 102, in accordance with an embodiment;
[0009] FIG. 1B illustrates an exploded view of a stator assembly 100, in accordance with an embodiment;
[0010] FIG. 2A is a top view of stator poles 104 with winding arrangement 102, in accordance with an embodiment;
[0011] FIG. 2B is a cross-sectional view of a single stator pole 104 along a cross-sectional line A-A shown in FIG. 2A, in accordance with an embodiment;
[0012] FIG. 2C is a detailed view of a cross-section of a stator pole 104 with winding arrangement 102, in accordance with an embodiment; and
[0013] FIG. 2D is a frontal view of the winding arrangement 102 with spacers 204, in accordance with an embodiment.
DETAILED DESCRIPTION
[0014] The following detailed description includes references to the accompanying drawings, which form part of the detailed description. The drawings show illustrations in accordance with example embodiments. The numerals in the figure represent like elements throughout the several views, exemplary embodiments of the present disclosure that are described. For convenience, only some elements of the same group may be labelled with numerals. The purpose of the drawings is to describe exemplary embodiments and not for production. Therefore, features shown in the figures are chosen for convenience and clarity of presentation only. Further, the figures may be out of scale, as they are intended for conveying the concept to help understand the working. Moreover, the language used in this disclosure has been principally selected for readability and instructional purposes and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter. These example embodiments are described in enough details to enable those skilled in the art to practice the present subject matter. However, it will be apparent to one of ordinary skill in the art that the present invention may be practiced without these specific details. The embodiments can be combined, other embodiments can be utilized, or structural and logical changes can be made without departing from the scope of the invention. The following detailed description is, therefore, not to be taken as a limiting sense.
[0015] In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one. In this document, the term “or” is used to refer to a non-exclusive “or,” such that “a or b” includes “a but not b,” “b but not a,” and “a and b,” unless otherwise indicated.
[0016] Reference in the specification to "one embodiment" or to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least one embodiment of the invention, and multiple references to "one embodiment" or "an embodiment" should not be understood as necessarily all referring to the same embodiment.
[0017] FIG. 1A is a perspective view of a stator assembly 100 with winding arrangement 102, in accordance with an embodiment. The stator assembly 100 may comprise a plurality of stator windings. Each stator winding may be in conformity with the winding arrangement 102. The stator assembly 100 may comprise of a plurality of stator poles 104. The stator winding 102 may be wound around each of the stator pole 104. The plurality of stator poles 104 may be disposed in a stator frame 106.
[0018] FIG. 1B illustrates an exploded view of a stator assembly 100 with the winding arrangement 102, in accordance with an embodiment. The stator assembly 100 may comprise the stator frame 106, the plurality of stator poles 104, a plurality of insulators 108 and the plurality of stator windings 102. The stator poles 104 may be an integral part of the stator frame 106. However, FIG. 1B depicts the stator poles 104 separately. It is to be noted that the illustration in FIG. 1B is for the sake of understanding and should not be considered as a limiting embodiment. The insulators 108 may be configured to provide insulation between the stator windings 102 and the stator poles 104. The stator pole 104 may be provided in a manner that the stator frame 106 may be configured to receive the plurality of stator poles 104. Each stator pole 104 may comprise a pair of the insulators 108. The pair of insulators 108 in each stator pole 104 may be configured to snugly accommodate the stator winding 102.
[0019] FIG. 2A is a top view of the stator poles 104 with winding arrangement 102, in accordance with an embodiment. The stator poles 104 may be disposed around a rotor (not shown) of the motor in a radial arrangement around an axis of rotation of the motor.
[0020] FIG. 2B is a cross-sectional view of a single stator pole 104 along a cross-sectional line A-A as seen in FIG. 2A, in accordance with an embodiment. The stator assembly 100 may comprise of the stator pole 104 wherein, each stator winding 102 may be embedded within a pair of slots 104a and 104b defined on the stator pole 104. Each of the slot 104a and 104b may be configured to accommodate the insulators 108. The stator winding 102 may be disposed within the pair of insulators 108 corresponding to the respective pair of slots 104a and 104b. The stator winding 102 may be configured to snugly fit into the insulators 108 in each stator pole 104 in a manner that at least a portion of the stator winding 102 interfaces with at least a portion of the insulators 108.
[0021] FIG. 2C is a detailed cross-sectional view of a stator pole 104 with the winding arrangement 102, in accordance with an embodiment. The winding arrangement 102 for the motor may be provided using electrically conductive flat strips 202. Each stator winding 102 may be formed by at least a layer of the flat strip 202. The flat strip 202 may be wound around each stator pole 104.
[0022] In an embodiment, a single flat strip 202 may be wound around the stator pole 104 forming a multi-layer flat strip 202 when wound across the pair of slots 104a and 104b of each stator pole 104. The stator winding 102 may be wound around the stator pole 104 to form a rectangular loop with rounded edges around the stator pole 104. The number of layers of the flat strip 202 in the winding arrangement 102 corresponds to the number of turns in the stator winding 102.
[0023] Referring to FIG. 2C, the electrically conductive flat strip 202 forming the stator winding 102 may be made of thin films. The thin films may be made of high conducting materials like, but not limited to, copper. The flat strips 202 may be laminated to ensure the adjacent layers in the winding arrangement 102 remain electrically isolated from each other. The flat structure of the laminated flat strip 202 may help in reducing skin effect along the length of the windings, when voltage is applied to the stator windings 102.
[0024] The flat topology of the flat strip 202 may provide a larger cross-sectional area in comparison to the conventional stranded round wires. Such flat topology of the flat strips 202 may enable the motor to achieve superior current ratings without any need for parallel connections, which eliminates the circulating current risk. Additionally, the rectangular shape and large cross-sectional area of the flat strips 202 significantly improves the fill factor and torque density of the stator.
[0025] Referring to FIG. 2C, the winding arrangement 102 may comprise at least three spacers 204 that may be disposed between adjacent layers of the flat strip 202. The three spacers 204 may be arranged along at least a cross-sectional length of the flat strip 202 to provide uniform spacing between adjacent layers of the flat strip 202, which in turn also ensures the robustness of the stator winding 102.
[0026] In yet another embodiment, a winding arrangement 102 may comprise at least one spacer 204 configured to be disposed between adjacent layers of the flat strip 202. Each spacer 204 may be arranged along at least a cross-sectional length of the flat strip 202 to provide uniform spacing between adjacent layers of the flat strip 202.
[0027] FIG. 2D is a frontal view of the stator winding 102 with spacers 204, in accordance with an embodiment. The winding arrangement 102 may comprise at least one spacer 204. The spacer 204 may be disposed between adjacent layers of the flat strip 202 that is wound around the stator pole 104. The spacers 204 may be configured to form a space 206 between the adjacent layers of flat strip 202.
[0028] In an embodiment, the spacers 204 may also be disposed towards, but not limited to, edges of the stator windings 102 between adjacent layers of flat strips 202 thereby forming the space 206 between the adjacent layers of flat strips 202.
[0029] Referring to FIG. 2D, the space 206 that may be formed by the spacers 204 may provide pockets for air circulation that may contribute to reducing the impedance in high frequency motors.
[0030] In an embodiment, the plurality of spacers 204 may be made of a non-conductive and thermal resistant material. In addition, the spacers 204 may be insulated to enhance the thermal resistivity of the spacers 204. The high thermal resistance of the spacers 204 may enable them to maintain the space between adjacent layers of the flat strip 202 even during the peak performance of the motor, thereby enabling longer duration working of the motor.
[0031] The conventional winding made of stranded round wire is wound around the stator pole to form significant end turns. The end turns may contribute to an increased flux density and eddy current losses. The placement of the stator winding 102 within the stator slots 104a and 104b may attribute the stator windings 102 to be in a pole centric form that may have nearly no end turns. The minimalistic presence or absence of end turns may help reduce eddy current losses significantly thereby enhancing the efficiency of the motor. The stator assembly 100 may be used for high frequency motors to reduce impedance in the motors that may be created due to skin effect and pockets provided for air circulation.
[0032] Although embodiments have been described with reference to specific example embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the system and method described herein. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.
[0033] Many alterations and modifications of the present invention will no doubt become apparent to a person of ordinary skill in the art after having read the foregoing description. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. It is to be understood that the description above contains many specifications, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the personally preferred embodiments of this invention.
[0034] The various embodiments have been described using detailed descriptions that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments comprise different features, not all of which are required in all embodiments. Some embodiments utilize only some of the features or possible combinations of the features. Many other ramification and variations are possible within the teaching of the embodiments comprising different combinations of features noted in the described embodiments.
[0035] It will be appreciated by persons skilled in the art that the various embodiments are not limited by what has been particularly shown and described herein above. Rather the scope of the invention is defined by the claims that follow.
, Claims:CLAIMS
We claim:
1. A winding arrangement (102) for a motor using electrically conductive flat strips (202), wherein the winding arrangement (102) comprises:
at least a layer of the flat strip (202) being wound around a stator pole (104); and
at least one spacer (204) disposed between adjacent layers of the flat strip (202) wound around the stator pole (104), thereby forming a space (206) between the adjacent layers of the flat strip (202).
2. The winding arrangement (102) for the motor as claimed in claim 1, wherein:
the stator pole (104) is configured to independently receive the stator winding (102); and
the stator pole (104) forms an integral part of a stator frame (106) of the motor to form a stator assembly (100) of the motor.
3. The winding arrangement (102) for the motor as claimed in claim 2, wherein each of the stator winding is configured to be individually replaceable.
4. The winding arrangement (102) for the motor as claimed in claim 3, wherein each independent flat strip (202) is configured to be wound externally and is configured to be disposed onto the stator pole (104).
5. The winding arrangement (102) for the motor as claimed in claim 4, wherein each independent winding arrangement (102) comprises of multiple layers of the flat strip (202), wherein the multiple layers of the flat strip (202) constitute number of turns of the winding arrangement (102).
6. The winding arrangement (102) for the motor as claimed in claim 1 wherein:
each of the plurality of spacers (204) are insulated; and
each of the spacer (204) is configured to maintain the space (206) between adjacent layers of the flat strip (202) when disposed between the adjacent layers of the flat strips (202).
7. The winding arrangement (102) for the motor as claimed in claim 6, wherein each of the plurality of spacers (204) is configured to be non-conductive and thermal-resistant.
Dated this 21st day of October 2022
(Digitally signed)
Kartik Puttaiah
Patent Agent-IN/PA-1809