DESC:[0001] The present invention relates to the stator assembly of a Rotating Machines. Specifically, it pertains to a busbar link within the stator assembly of the Permanent magnet synchronous motor (PMSM) that is designed to efficiently transmit power to the stator coil, minimize heat generation and also improve connectivity between stator windings and the busbar assembly.

BACKGROUND:
[0002] A busbar is a strip/bar typically made of copper or aluminium or brass or any metal that is used to conduct electricity within a motor. Specifically, the busbar is used to carry electrical current from the power supply to the stator coil in the stator assembly of the motor. The purpose of the busbar is to provide a low-resistance path for the current to flow through, which helps to ensure that the stator coil receives the necessary power to operate efficiently.
[0003] The connection between the phase cables in busbar and the stator of the motor is typically made through the use of connectors, such as bolts or screws. The busbar is usually fastened to the stator in a way that ensures a good electrical connection and helps to prevent any electrical resistance or heat generation.
[0004] In a Permanent Magnet Synchronous Motor (PMSM), the stator is typically made up of a series of winding coils that are connected to a power supply. The busbar is used to conduct electricity from the power supply to the stator coils, which helps to generate the stator field flux (magnetic field) needed to rotate the motor's rotor.
[0005] The use of a busbar in rotating machines can provide several benefits, including improved efficiency and reduced heat generation. By providing a low-resistance path for the current to flow through, the busbar can help to minimize electrical losses and improve the overall performance of the motor. Additionally, the use of a busbar can help to distribute the electrical load more evenly across the stator coils, which can reduce the risk of overheating and prolong the life of the motor.
[0006] Busbars in the existing prior art have multiple phase terminals/cables that correspond to the stator coil windings, typically labelled as "U," "V," and "W” terminals. These terminals are used to distribute the electrical current to the appropriate winding in the stator coil. Each phase coil conductors (i.e., each terminal of the busbar) are connected by using soldering/welding process and a butt connector/hook may be used to connect these phase cables.
[0007] For example, Chinese Patent Application Number 115347710 to Guangdong Welling Auto Parts Co Ltd and Anhui Welling Auto Parts Co Ltd entitled “Busbar, motor, steering system and vehicle” discloses a busbar, comprising: a confluence framework; four busbars which comprise a main body part and welding hooks, the welding hooks are arranged on the main body part, connecting parts are arranged on the welding hooks, part of the welding hooks and part of the connecting parts are exposed out of the busbar framework, one main body part is positioned in the surrounding area of the adjacent main body part, the structures of any two connecting parts are the same, and the distances between the end parts, far away from the central axis of the busbar framework, of any two connecting parts and the central axis of the busbar framework are equal; and the terminal assembly is connected with the connecting part.
[0008] The existing busbars use welding to connect the terminal coils, but this method has several drawbacks such as wrong connection between coils and phases, missing of strands or unconnected conductors, which turns motor to non-working condition. Existing busbars are difficult to manufacture due to their bulk size, complicated serviceability due to welding process and the assembly process is time-consuming. Additionally, the electrical conductivity of the busbars is slightly reduced due to the welding process.
[0009] In order to overcome the aforementioned limitations, the present invention provides design and manufacturing of connecting rings and notches for different phases of the busbars that eases the manufacturing process with compact design, reduces cycle time, is safe to operate, generates less heat and enhances electrical conductivity.

OBJECTIVES OF THE INVENTION:
[0010] The primary objective of the present invention is to provide a mechanism for connecting busbars in stator assembly using connecting rings and notches for different phases of the busbars in the stator of a rotating machines.
[0011] Another objective of the present invention is to provide ease of serviceability, ease the manufacturing process with single output, ensuring safe operation, generating less heat and enhancing electrical conductivity of the motor.
[0012] Yet another objective of the present invention is to reduce the cycle time involved in manufacturing the busbar phases.
[0013] Still another objective of the present invention is to provide fuse link to prevent the stator coil from burning issue.

SUMMARY:
[0014] The following summary is provided to facilitate a clear understanding of the new features in the disclosed embodiment, and it is not intended to be a full, detailed description. A detailed description of all the aspects of the disclosed invention can be understood by reviewing the full specification, the drawing, and the claims and the abstract, as a whole.
[0015] In order to achieve the aforementioned objectives, the present invention discloses a mechanism for connecting busbars in stator assembly using connecting rings and notches for different phases of the busbars in the stator of a rotating machines.
[0016] According to present invention, the rotating machine has stator assembly with field windings to produce field flux in the motor. The stator windings are connected to three phases, namely Phase U, Phase V and Phase W, and also a neutral ring. These three phases have more coils with in and out wires which are connected to the phase cables to give the power supply to the stator winding. For establishing the connection between coil to phase, a busbar link is provided. This busbar link provides power supply to the appropriate coil, where all winding adjacent coil leads starts each 30° angle (approximately), with each coil link approximately having 1.5mm gap between each other.
[0017] In accordance with the present invention, each busbars have four links namely, Phase U link, Phase V link, Phase W link and a Neutral link.
[0018] In the present invention, the busbar includes fuse links provided in each different phase of the busbar protects stator coil from burning related issues.
[0019] Thus, the present invention provides design of busbars with single output which is easy to manufacture, reduces cycle time, safe to operate, generates less heat and improves electrical conductivity.

REFERENCE NUMERALS
Busbar (10)
Phase U Cable (1)
Phase V Cable (2)
Phase W Cable (3)
Insulation mold (4)
U notch for U-Phase (11)
U notch for V-Phase (12)
U notch for W-Phase (13)
U notch for U-Phase cable crimping (21)
U notch for V-Phase cable crimping (22)
U notch for W-Phase cable crimping (23)
U notch for neutral coil crimping (24)
U-Phase Fuse Link (31)
V-Phase Fuse Link (32)
W-Phase Fuse Link (33)
U-Phase connecting ring (41)
V-Phase connecting ring (42)
W-Phase connecting ring (43)
Phase U,V,W Neutral connecting ring (44)
M4 Internal Threaded Stud for U-Phase cable connection (21a)
M4 Internal Threaded Stud for V-Phase cable connection (22a)
M4 Internal Threaded Stud for W-Phase cable connection (23a)
M4 External Threaded Stud for U-Phase cable connection (21b)
M4 External Threaded Stud for V-Phase cable connection (22b)
M4 External Threaded Stud for W-Phase cable connection (23b)
M4 Eyelet (Straight) for U-Phase cable connection (21c)
M4 Eyelet (Straight) for V-Phase cable connection (22c)
M4 Eyelet (Straight) for W-Phase cable connection (23c)
M4 Eyelet (Flat) for U-Phase cable connection (21d)
M4 Eyelet (Flat) for V-Phase cable connection (22d)
M4 Eyelet (Flat) for W-Phase cable connection (23d)

BRIEF DESCRIPTION OF THE DRAWINGS:
[0020] The present invention will be better understood fully from the detailed description that is given herein below with reference to the accompanying drawings of the preferred embodiments of the present invention, which, however, should not be deemed to be a limitation to the invention to the specific embodiments, but, are for the purpose of explanation and understanding only.

FIG. 1 illustrates the busbar assembly according to the present invention;
FIG. 2 illustrates the different phases of connecting rings and fuse link designed according to the present invention;
FIG. 3 (a) shows the structure of neutral connecting ring of the phase U, V, W;
FIG. 3 (b) shows the structure of U-phase connecting ring;
FIG. 3(c) shows the structure of V-phase connecting ring;
FIG. 3(d) shows the structure of W-phase connecting ring;
FIG. 4 illustrates the exploded view of the busbar assembly;
FIG. 5 illustrates the design of U-type notch for crimping different phase cables according to an embodiment of the present invention;
FIG. 6 illustrates the design of different phase cables using internal threaded stud fastener according to an embodiment of the present invention;
FIG. 7 illustrates the design of different phase cables using external threaded stud fastener according to an embodiment of the present invention;
FIG. 8 illustrates the design of different phase cables using Eyelet straight fastener according to an embodiment of the present invention;
FIG. 9 illustrates the design of different phase cables using Eyelet flat fastener according to an embodiment of the present invention;
FIG. 10 illustrates the stator assembly with busbars connection;
FIG. 11 illustrates the busbar link with W-phase connection ring;
FIG. 12 (a) – (c) illustrate the U, V, W phase ring with Neutral ring; and
FIG. 13 illustrates the winding diagram of different phase cables according to present invention.

DETAILED DESCRIPTION OF THE INVENTION:
[0021] The present invention discloses a mechanism for connecting phase cables to all three-phase winding coil conductor and coil neutral conductor connection by using busbar assembly in stator assembly of rotating machines.
[0022] According to present invention and referring to FIG. 1, busbar assembly (10) in rotating machines, preferably in Permanent Magnet Synchronous Motor (PMSM), but not limited to the same is shown. The motors in rotating machines are connected to a stator coil of the motor, has an insulator made of insulation materials (4) that forms a body of the busbar; a first terminal protrusively formed at a lower side of a periphery of the insulator and connected to the stator coil neutral link (24) and second terminal is connected to the stator coil Phase U, and third-layer terminal is connected to the stator coil phase V and fourth layer is connected to the stator coil phase W. Phase U, Phase V, Phase W coils are connected to the phase wire subsequently.
[0023] Referring to FIG. 2, the different phases of connecting rings (41, 42, 43) and fuse link (31, 32, 33) designed according to the present invention is provided. The diagram shows the overall view of the busbar assembly and its connection terminals, and also shows where the coil conductors are connected and where the phase cables are connected, for example in the FIG. 2, yellow colour is phase U, phase U coil conductors (1) are connected in yellow colour U notch (11), like wise other two phase (2, 3) will be connected in green and blue (12, 13). The busbar assembly is preferably made of copper/brass connecting ring and insulation mould is preferably made of Polyphthalamide (PPA) plastic Material, but not limited to the same.
[0024] According to present invention, the PMSM has stator assembly with field windings to produce field flux in the motor. The stator windings have three non-limiting different phases, namely Phase U, Phase V and Phase W. These three phases have more coils with in and out wires (21, 22, 23) which are connected to the phase cables to give the power supply to the stator winding. FIG. 2 illustrates the different phases of connecting rings (41, 42, 43) and fuse links (31, 32, 33) in busbar designed according to the present invention. Fuse links provided in each different phase protect stator coil from burning related issues. For establishing the connection between coil to phase, a busbar link is provided. This busbar link provides power supply to the appropriate coil, where all winding adjacent coil leads starts each 30° angle (approximately), with each coil link approximately having 1.5mm gap between each other.
[0025] FIG. 3(a) shows the structure of neutral connecting ring of the phase U, V, W (44). Neutral link is used to provide star or delta connection based on motor winding design. and FIGS. 3(b) shows U Phase connecting link which is used to provide power supply to phase U coil conductors, FIGS. 3(c) shows V Phase connecting link which is used to provide power supply to phase V coil conductors, FIGS. 3(d) shows W Phase connecting link which is used to provide power supply to phase W coil conductors. All U, V, W phase coils conductors are connected to neutral busbar for providing the star connection or delta connection.
[0026] FIG. 4 illustrates the exploded view of the busbar assembly which includes insulation mould which acts as cover for different types of connecting rings.
[0027] As illustrated in FIGS. 3(a) – 3(d), the busbar has four links (Phase U link, Phase V link, Phase W link, and Neutral link). The connection mechanism for the phases U, V and W are provided below.

Phase U Link:
[0028] This phase U link is connected to the Phase U coil leads, Phase U winding has four coils, each four coils have four in and four out coil leads, these phase U- four coil in leads are connected to phase U link, Phase U- four coil out leads are connected to Neutral busbar link. Phase U busbar link has integrated fuse link, this fuse link is used to protect stator coil from burning failure due to over current issue. Fuse link is blown when exceeds the rated current limits, so coil will not be affected by the over current issue, so motor is protected from the motor burning issue.
Phase V Link:
[0029] This phase V link is connected to the Phase V coil leads, Phase V winding has four coils, each four coils have four in and four out coil leads, these phase V- four coil in leads are connected to phase V link, Phase V- four coil out leads are connected to Neutral busbar link. Phase V busbar link has integrated fuse link, this fuse link is used to protect stator coil from burning failure due to over current issue. Fuse link is blown when exceeds the rated current limits, so coil will not be affected by the over current issue, so motor is protected from the motor burning issue.

Phase W Link:
[0030] This phase W link is connected to the Phase W coil leads, Phase W winding has four coils, each four coils have four in and four out coil leads, these phase W- four coil in leads are connected to phase W link, Phase W- four coil out leads are connected to Neutral busbar link. Phase W busbar link has integrated fuse link, this fuse link is used to protect stator coil from burning failure due to over current issue. Fuse link is blown when exceeds the rated current limits, so coil will not be affected by the over current issue, so motor is protected from the motor burning issue.
[0031] Hereinafter, design of different types of fasteners used to connect different phase cables are provided (in conjunction with drawings) in accordance with various embodiments of the present invention.
[0032] FIG. 6 illustrates the design of different phase cables using internal threaded stud (21a, 22a, 23a), where screw is used for tightening the phase cable lug (eyelet) fastener according to an embodiment of the present invention; FIG. 7 illustrates the design of different phase cables using external threaded stud (21b, 22b, 23b). In this mechanism, hexagonal nut is used for tightening the phase cable lug (eyelet) fastener according to an embodiment of the present invention; FIG. 8 illustrates the design of different phase cables using straight eyelet (21c, 22c, 23c). FIG. 9 illustrates the design of different phase cables using Eyelet flat (21d, 22d, 23d). Here, screw and hexagonal nut is used for tightening the phase cable lug (eyelet) fastener according to an embodiment of the present invention. Each fastening mechanism disclosed above provides ease of serviceability i.e., Phase cable can be easily removed and tightened. FIG. 10 illustrates the stator assembly with busbars connection which shows the how busbar is assembled in stator and housing assembly of PMSM motor and FIG. 11 illustrates the busbar link with W-phase connection ring (43).
[0033] FIGS.12 (a) to (c) show the U, V and W phase ring (41, 42, 43) with neutral ring (44). In case of 12 slot motor, each stator phase coil connects with one phase ring terminal and one neutral ring terminal. So, the 12- stator coil will have 24 leads and the leads connect to 12 phase ring terminal and output is connected to 12 neutral ring terminals.
[0034] FIG. 13 illustrates the winding diagram of different phase cables according to present invention.
[0035] In the motor busbar system, no. of phases decides the no. of busbar rings. So, if three phase motor has 3 phase rings and one neutral ring, then a 6- phase motor has 6 phase rings and one neutral ring, hence, number of rings are based on number of phases only.
[0036] Thus, the present invention provides mechanism for connecting busbars in stator assembly using connecting rings and notches for different phases of the busbars in the stator of the motor. The proposed mechanism provides easy manufacturing assembly process, easy serviceability compact design with single output, reduces cycle time, safe to operate, generates less heat and thereby improves electrical conductivity.
,CLAIMS:1. A busbar assembly (10) mechanism for connecting a stator coil to a plurality of phases, the mechanism comprising:
a plurality of connecting rings (41,42,43,44) cased within an insulation mould (cover);
a plurality of fuse links (31,32, 33), a plurality of notches (21,22,23) and fastening mechanisms on the periphery of the insulation mould;
wherein an electric connection between the stator coil to the plurality of phases (1,2,3, neutral) is established.
2. The mechanism (10) as claimed in claim 1, wherein the plurality of phases comprises Phase U (1), Phase V (2), Phase W (3) and neutral, wherein
a first terminal on the periphery of the insulation mould is linked to the stator coil neutral;
a second terminal on the periphery of the insulation mould is linked to the stator coil Phase U;
a third-layer terminal on the periphery of the insulation mould is linked to the stator coil phase V; and
a fourth terminal on the periphery of the insulation mould is linked to the stator coil phase W.
3. The mechanism as claimed in claim 1, wherein the neutral connecting ring (44) comprises
the Phase U connecting ring (41) supplying power to Phase U coil conductors;
the Phase V connecting ring (42) supplying power to Phase U coil conductors;
the Phase V (43) connecting ring supplying power to Phase U coil conductors; wherein
the Phases U,V,W coil conductors are connected to the neutral connecting ring (44).
4. The mechanism as claimed in claim 1, wherein the busbar assembly (10) maintains approximately a gap of 1.5mm between the connections from the stator coil and the plurality of phases.
5. The mechanism as claimed in claim 1, wherein the neutral connecting ring (44) of the Phase U, Phase V and Phase W provides a star or delta connection.
6. The mechanism as claimed in claim 1, wherein the busbar assembly is made preferably from copper or brass.
7. The mechanism as claimed in claim 1, wherein the insulation mould is made from Polyphthalamide (PPA) plastic, but not limited to the same.
8. The mechanism as claimed in claim 1, wherein the fuse links (31, 32, 33) are configured to protect the stator coil from burning.
9. The mechanism as claimed in claim 1, wherein the fastening mechanism is selected from a group comprising internal threaded stud fastener, external threaded stud fastener, eyelet straight fastener and eyelet flat fastener.