Description:A MOTOR ASSEMBLY
FIELD OF THE INVENTION
[0001] The present invention disclosure to a motor assembly. More particularly, the present disclosure relates to a permanent magnet motor assembly with reduced 5 cogging effects.
BACKGROUND
[0002] Conventional surface permanent magnet (SPM) motors encounters certain limitations and challenges that necessitate the exploration of alternative motor 10 configurations. One prominent issue with SPM motors lies in their comparatively lower efficiency and power density. This deficiency arises primarily due to the placement of magnets on the outer or inner surface of the rotor in the SPM motors, thereby introducing a larger air gap between the magnets and the stator. As a consequence, this enlarged air gap can precipitate increased magnetic losses and 15 diminished magnetic flux density within the motor assembly. Consequently, the overall efficiency and power output of the SPM motors may be adversely affected, particularly in applications necessitating low-speed operation coupled with high torque requirements.
[0003] The configuration of SPM motors introduces another operational hurdle in 20 the form of non-uniform air gaps between the magnets and the stator. This irregularity in air gap distribution exacerbates the occurrence of cogging torque, which can significantly impede motor performance and operational smoothness. The presence of cogging torque undermines the motor's ability to deliver consistent and reliable torque output, thereby hampering its overall performance. 25
[0004] The positioning of magnets on the outer surface presents inherent challenges in the realm of cooling and thermal management. Operational heat generated within the motor must be efficiently dissipated to safeguard against overheating and uphold consistent and reliable performance standards. However, the very configuration that defines SPM motors is the presence of an air gap 30 between the magnets and the stator and the same poses a significant hurdle to effective heat transfer mechanisms. This impediment complicates the task of
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managing temperature rise within the motor and sustaining optimal operating conditions over prolonged periods of use. [0005] Further, the exposure of magnets on the motor's surface, rendering them susceptible to mechanical damage and external impacts. The SPM motors exhibit a heightened risk of demagnetization or physical harm due to their exposed
5 positioning. This heightened vulnerability poses a significant threat to the overall performance and reliability of SPM motors. Instances of mechanical impact can lead to compromised magnet integrity, resulting in diminished motor efficiency and reliability over time.
[0006] The SPM motors rely on magnets positioned on the motor's surface for 10 operation, the increased reliance on magnets inherently escalates production costs. This heightened magnet usage not only impacts the upfront manufacturing expenses but also contributes to increased operational losses within the motor system. The additional magnets in SPM motors exacerbate magnetic losses, consequently diminishing the overall efficiency of the motor assembly. 15
[0007] The SPM motors also suffered from the plaguing issues, more specifically, the SPM motors is their diminished efficiency attributable to magnet loss and the increased air gap between the magnets and the stator. These losses can significantly impair the overall performance of the machine, hampering its operational efficacy. Further, the positioning of magnets on the outer or inner surface of the rotor renders 20 them susceptible to mechanical stress and damage, posing concerns for the motor's durability and reliability. Furthermore, heat dissipation presents a formidable challenge for SPM motors, particularly at high speeds, exacerbating thermal management issues. Moreover, ensuring proper alignment and bonding of magnets during manufacturing can prove to be arduous, impacting manufacturability and 25 increasing production costs. The extensive usage of magnets further adds to the financial burden associated with SPM motors.
[0008] The surface mounting of magnets on the rotor imposes limitations on the achievable power density of the motor, which may fall short of meeting the demands of high-power applications. 30
[0009] Given these challenges, there is an urgent requirement to optimize the efficiency, power density, and operational characteristics of the SPM motors.
[00010] The above information as disclosed in this background section is only for enhancement of understanding of the background of the disclosure and therefore it
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may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 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 of the present disclosure, as set forth in the remainder of the present disclosure and
5 with reference to the drawings.
SUMMARY
[00011] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not 10 restrictive of the invention, as claimed.
[00012] In one of the embodiments of the present disclosure, a motor assembly, comprising a stator, a rotor and plurality of permanent magnets. The stator comprising a plurality of stator teeth and a plurality of stator grooves. The rotor comprising an inner core with a plurality of openings. Further, the plurality of 15 openings in the inner core of the rotor is configured to accommodate the plurality of permanent magnets. Furthermore, the rotor and the inner core of the rotor are composed of soft magnetic composite (SMC) material.
[00013] In one of the embodiments of the present disclosure, the stator comprising a plurality of stator slots defined between the plurality of stator teeth. Further, the 20 plurality of stator slots and the plurality of stator teeth are configured circumferentially, one after another, around a stator core of the stator. Furthermore, the plurality of stator grooves are provided over top surfaces, of the plurality of stator teeth, facing towards the inner core of the rotor. The dimensions of the plurality of stator grooves are different from each other. 25
[00014] In one of the embodiments of the present disclosure, the inner core of the rotor comprises a plurality of protuberance configured between the plurality of openings and protruded towards the stator. Further, the plurality of openings and the plurality of protuberance are configured circumferentially and one after another. Furthermore, the rotor and the inner core of the rotor are composed of a soft 30 magnetic composite (SMC) material. Moreover, the protuberance is filled using a soft magnetic composite (SMC) material, and wherein the SMC material is coated with an insulating material.
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[00015] In one of the embodiments of the present disclosure, the plurality of stator teeth and the plurality of stator grooves are disposed around a circumference and oriented radially towards a stator center, and defining slots interposed between each of the plurality of stator teeth and the rotor rotatable relative to the stator about an axis of rotation which coincides with a stator center.
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[00016] In one of the embodiments of the present disclosure, the plurality of stator slots are substantially V-shaped. Further, the plurality of stator slots are configured to receive insulated windings configured on the plurality stator teeth.
[00017] In one of the embodiments of the present disclosure, the plurality of stator teeth and the plurality of stator grooves are arranged to create a sinusoidal magnetic 10 flux distribution within the motor assembly during operation of the motor assembly. Further, the plurality of permanent magnets are arranged circumferentially on the inner core of the rotor.
[00018] In one of the embodiments of the present disclosure, the rotor further comprises a shaft extending axially from the inner core. Further, the shaft is 15 configured to facilitate coupling with an external load. Furthermore, the shaft comprises multiple bearings positioned along a length of the shaft.
[00019] A method for constructing surface permeant magnet motor assembly comprising steps of providing a stator comprising a plurality of stator teeth and a plurality of stator grooves. Further, forming a rotor comprising an inner core with 20 a plurality of openings. Furthermore, inserting plurality of permanent magnets within the plurality of openings of the rotor. Moreover, filling a protuberance with a soft magnetic composite (SMC) material. The protuberance is formed in the inner core of the rotor where the plurality of permanent magnets is not located.
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BRIEF DESCRIPTION OF FIGURES:
[00020] The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate preferred embodiments of the invention, and together with the general description given above and the detailed description given below, serve to explain features of the invention. 30
[00021] Figure 1a illustrates a perspective view of a motor assembly, in accordance with an embodiment of the present subject matter.
[00022] Figure 1b depicts a front view of the motor assembly in accordance with an embodiment of the present subject matter.
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[00023] Figure 2 depicts an exploded view of the motor assembly in accordance with an embodiment of the present subject matter.
[00024] Figure 3 illustrates a sectional view of a rotor of the motor assembly in accordance with an embodiment of the present subject matter.
[00025] Figure 4 illustrates sectional view of a stator and a sectional view of grooves 5 on stator slots of the motor assembly in accordance with an embodiment of the present subject matter.
[00026] Figure 5 illustrates method for constructing a motor assembly in accordance with an embodiment of the present subject matter.
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DETAILED DESCRIPTION
[00027] Exemplary embodiments detailing features of the present disclosure in accordance with the present subject matter will be described hereunder with reference to the accompanying drawings. Various aspects of different embodiments of the present invention will become discernible from the following description set 15 out hereunder. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the present subject matter. Further, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Additionally, all numerical terms, such as, but not limited to, “first”, “second”, “third”, “primary”, 20 “secondary”, “main” or any other ordinary and/or numerical terms, should also be taken only as identifiers, to assist the reader's understanding of the various elements, embodiments, variations and/or modifications of the present disclosure, and may not create any limitations, particularly as to the order, or preference, of any element, embodiment, variation and/or modification relative to, or over, 25 another element, embodiment, variation and/or modification.
[00028] The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar elements. While embodiments may be described, modifications, adaptations, and other implementations are 30 possible. For example, substitutions, additions, or modifications may be made to the elements illustrated in the drawings, and the methods described herein may be modified by substituting, reordering, or adding stages to the disclosed methods. Accordingly, the following detailed description does not limit the claimed subject
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matter. Instead, the proper scope of the claimed subject matter is defined by the appended claims. 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 5 principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof. [00029] Further, various embodiments disclosed herein are to be taken in the illustrative and explanatory sense and should in no way be construed as limiting of the present disclosure. All joinder references (e.g., attached, affixed, coupled, 10 disposed, etc.) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer those two elements are directly connected to 15 each other.
[00030] It will also be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular disclosure. Additionally, any signal hatches in the 20 drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically specified.
[00031] The at least one object of the present disclosure is the reduction of the motor's size and weight, thereby facilitating a more compact and lightweight motor. This optimization is particularly advantageous for applications where weight 25 constraints are paramount, enabling the motor to be seamlessly integrated into space-limited environments without compromising performance or functionality.
[00032] The at least one object of the present disclosure is towards enhancing motor efficiency, with a consequential reduction in losses and peak current. By minimizing inefficiencies inherent in traditional motor, the present disclosure 30 contributes to improved overall energy efficiency, thereby maximizing operational efficacy and minimizing energy wastage.
[00033] The at least one object of the present disclosure is to develop a cost effective, better efficient inset magnet solution to overcome the challenges
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associated with the existing surface mounted permeant magnet (SPM) motor. Further, the inset magnet motor of the present disclosure revolutionizes the placement of magnets within the motor, providing significant improvements in performance that suits low speed applications. [00034] The at least one object of the present disclosure is on mitigating cogging 5 torque, a prevalent issue in conventional motor configurations. Through the incorporation of the present disclosure, the motor achieves lower cogging torque compared to existing solutions available in the art, thereby enhancing operational smoothness and precision.
[00035] The at least one object of the present disclosure is intrinsically geared 10 towards enhancing cost-effectiveness. By leveraging advancements in magnet weight reduction, streamlined assembly processes, and minimized maintenance requirements. Accordingly, the present disclosure drives down overall costs, rendering the motor more economically viable for a diverse range of applications.
[00036] The permanent magnet synchronous motors (PMSMs) comprises surface 15 permanent magnet (SPM) and interior permanent magnet (IPM) motor, also known as inset magnet motor, configurations. Further, the inset magnet motor, which represents a departure from conventional motor by embedding magnets directly within the rotor core offers numerous advantages over traditional surface-mounted magnet configurations, including improved magnetic field distribution, reduced 20 losses, and enhanced power density.
[00037] The surface permeant magnet motor assembly (500), herein after also mentioned as motor assembly (500), specifically configured for use in vehicles, however, this motor assembly finds utility in a range of transportation modes, including two-wheelers, three-wheeler, four-wheelers, electric boats, electric trains, 25 electric marine industry renewable energy systems such as wind turbines, and other electric-powered equipment or devices. Its adaptability extends beyond the automotive sector, encompassing diverse industries such as robotics, aerospace, and industrial machinery appliances.
[00038] Figure 1a illustrates a perspective view of a motor assembly (500) and figure 30 1b depicts a front view of the motor assembly (500) in accordance with an embodiment of the present subject matter. Figure 2 depicts an exploded view of the motor assembly (500). The figures 1a, 1b and 2 are taken together for describing the present subject matter.
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[00039] The motor assembly (500) described encompasses essential components for its operation. More specifically, at its core lies the stator (300), a stationary component housing a series of stator teeth (306) and stator grooves (302). The same is configured to provide structural support and facilitate the generation of electromagnetic fields essential for motor function. Complementing the stator is the 5 rotor (100), which serves as the rotating element of the motor assembly (500). Central to the rotor's is its inner core (102), comprising a series of openings (308) which are arranged to accommodate a plurality of permanent magnets (200). The plurality of permanent magnets (200) is configured for generating the magnetic fields necessary for the operation of the motor assembly (500). Further, the 10 configuration of the openings within the rotor's core is precisely engineered to house the plurality of permanent magnets (200) securely and efficiently, ensuring optimal performance and stability of the motor assembly.
[00040] The stator teeth provide anchorage for the winding coils and facilitate the creation of a rotating magnetic field when energized. Further, the stator grooves 15 serve to optimize the magnetic flux distribution within the motor, ensuring efficient energy conversion. Furthermore, the rotor (100), its inner core (102) is engineered with a specific configuration of openings (308) intended to house the plurality of permanent magnets (200). These magnets are positioned within the rotor (100) to interact with the magnetic field generated by the stator (300), thereby inducing 20 rotational motion. Accordingly, the rotor (100) ensures smooth and consistent operation of the motor assembly, fulfilling its intended purpose effectively and reliably.
[00041] In one of the embodiments of the present disclosure, soft magnetic composite (SMC) material is used for both the rotor (100) and its inner core (102). 25 SMC material is a type of composite material engineered specifically for applications requiring high magnetic permeability and low magnetic losses. Further, by incorporating SMC material into both the rotor and its core, the motor assembly achieves several key benefits. Firstly, SMC material offers superior magnetic properties compared to traditional materials like steel laminations, 30 enabling more efficient energy conversion within the motor. Further, SMC material exhibits excellent mechanical properties, such as high strength and durability, ensuring the robustness and longevity of the rotor assembly. Furthermore, the use
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of SMC material contributes to reducing eddy current losses and improves the overall performance and efficiency of the motor. [00042] Soft magnetic composite (SMC) materials encompass a range of alloys and composites tailored for optimal magnetic performance and efficiency. Fe-Si alloys are prominent, comprising iron and silicon for excellent magnetic properties, 5 rendering them ideal for electrical machines and transformers. Nanocrystalline alloys, defined by fine crystallite structures, offer low coercivity and high permeability, suiting high-frequency applications like power electronics. Iron powder cores, featuring insulated iron particles, provide high permeability and low core losses, making them suitable for inductors and power supply circuits. 10 Amorphous alloys, with disordered atomic structures, exhibit low coercivity and high permeability, finding utility in transformers and magnetic sensors. Ferrite powders, ceramic materials composed of iron oxide and metal oxides, offer high electrical resistivity, catering to applications in electromagnetic interference suppression and microwave devices. These SMC materials collectively enable 15 diverse industries to achieve superior magnetic performance and efficiency in various applications, ranging from power generation to telecommunications.
[00043] In one of the embodiments of the present disclosure, the rotor (100) is responsible for housing the magnets and facilitating the interaction with the stator's magnetic field to produce torque and rotational motion. Further, the rotor core is 20 constructed using soft magnetic composite (SMC) material and the benefit of utilizing SMC material in the rotor core lies in its ability to minimize eddy current losses, thereby mitigating energy dissipation and improving the overall efficiency of the motor. Additionally, SMC material boasts optimized magnetic properties characterized by high permeability, which enables efficient transfer of magnetic 25 flux between the rotor and stator. This optimized flux transfer enhances the motor's overall performance by ensuring effective utilization of magnetic forces to drive rotation, thereby contributing to increased efficiency and operational effectiveness.
[00044] In one of the embodiments of the present disclosure, the stator (300) comprises a plurality of stator slots (304) defined between the plurality of stator 30 teeth (306). Further, the plurality of stator slots (304) and the plurality of stator teeth (306) are configured circumferentially, one after another, around a stator core of the stator (300). The plurality of stator grooves (302) are provided over top surfaces, of the plurality of stator teeth (306), facing towards the inner core (102) of the rotor
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(100). Furthermore, dimensions of the plurality of stator grooves (302) are different from each other. More specifically, in the stator (300), the plurality of stator grooves (302) are configured over the top surfaces of the stator teeth (306), oriented towards the inner core (102) of the rotor (100). The plurality of stator grooves (302) are configured to optimize the magnetic flux distribution within the motor assembly
5 (500). In one of the embodiments of the present disclosure, each stator groove of the plurality of stator grooves (302) is dimensioned differently from the others, for achieving a non-uniform air gap between the stator and the rotor. By varying the dimensions of these grooves, users can fine-tune the magnetic field strength and distribution across the motor, thereby enhancing its performance and efficiency. 10 [00045] The plurality of stator grooves (302) serve multiple functions within the motor assembly (500). Firstly, they help to reduce cogging torque by creating variations in the magnetic field strength along the air gap between the stator and rotor. This minimizes the resistance encountered by the rotor during rotation, leading to smoother operation and improved efficiency. Further, the non-uniform 15 dimensions of these grooves contribute to optimizing the magnetic field distribution, ensuring maximum utilization of magnetic flux for generating torque. Furthermore, the circumferential arrangement of the stator slots (304) and teeth (306) around the stator core facilitates efficient magnetic coupling with the rotor, enabling precise control over the motor's rotational behaviour. 20
[00046] Figure 3 illustrates a sectional view of a rotor (100) of the motor assembly (500) and Figure 4 illustrates sectional view of a stator (300) and a sectional view of grooves (302) on stator slots (304) of the motor assembly (500). The figures 3 and 4 are taken together for describing the present subject matter.
[00047] In the motor assembly (500), the stator (300) is configured for generating 25 the magnetic field necessary for the motor operation. It consists of a series of stator slots (304) where conductive windings or coils are placed, enabling the creation of electromagnetic forces. Further, the stator (300) comprising plurality of the stator grooves (302) that are positioned over the plurality of the stator teeth (306). These stator grooves (302) serve multiple functions, including providing structural 30 support and housing for the windings while ensuring optimal magnetic field distribution. Furthermore, the top surface of the stator grooves (302) is configured to be uneven in surface to enhance the motor performance. More specifically, by directing the uneven surface towards the rotor core, the magnetic flux distribution
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is optimized, leading to improved efficiency and reduced losses within the motor assembly (500). This configuration maximizes the interaction between the stator (300) and rotor (100) components, resulting in smoother operation and enhanced overall performance of the motor assembly (500). Furthermore, the uneven top surface of the stator grooves is engineered to face towards the inner core (102) of 5 the rotor (100). [00048] In one of the embodiments of the present disclosure, the grooves (302) is introduced in the stator teeth (306), either as single or multiple configurations, to enhance the motor's saliency. This feature reduces cogging and torque ripple, contributing to smoother motor operation and improved efficiency. Additionally, 10 the housing serves to provide structural support and protection for internal motor components against environmental factors, dust, and moisture. It also helps contain electromagnetic interference generated during motor operation. The configuration and material choice of the housing influence the motor's durability and thermal management, with adequate cooling features such as fins or vents aiding in effective 15 heat dissipation to ensure optimal operating temperatures.
[00049] In one of the embodiments of the present disclosure, the inner core (102) of the rotor (100) comprises a plurality of protuberance (310) configured between the plurality of openings (308) and protruded towards the stator (300). Accordingly, the protuberance (310) within the inner core (102) allows for the selective 20 placement of the plurality of permanent magnets (200) while ensuring an even distribution throughout the rotor (100). This enables the motor assembly (500) to achieve a balanced magnetic field, essential for smooth and efficient operation. Further, the protuberance (310) facilitates the insertion of other materials to enhance the overall characteristics of the rotor assembly. Furthermore, a soft 25 magnetic composite (SMC) material is utilized to fill the protuberance (310). By filling the protuberance with SMC material, the motor assembly benefits from improved magnetic flux distribution and reduced losses, ultimately leading to enhanced efficiency and performance.
[00050] In one of the embodiments of the present disclosure, the inner core (102) of 30 the rotor (100) in the motor assembly (500) interact with the stator (300) and facilitate the generation of rotational motion. Within this inner core (102), a plurality of protuberances (310) is configured to protrude towards the stator (300) and are positioned between a series of openings (308) in the core. The arrangement
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of these openings and protuberances is circumferential, forming a continuous pattern around the core. The plurality of protuberances (310) within the inner core serves several important functions in the operation of the motor assembly. Firstly, the plurality of protuberances (310) contributes to the overall structural stability and rigidity of the rotor core, ensuring that it maintains its shape and integrity 5 during operation. The plurality of protuberances (310) are placement between the openings helps to regulate the distribution of magnetic flux within the motor assembly (500). By protruding towards the stator, these protuberances help to focus and direct the magnetic field generated by the stator's windings, enhancing the efficiency and effectiveness of the motor's operation. Furthermore, both the rotor 10 and its inner core are constructed using a soft magnetic composite (SMC) material. [00051] In one of the embodiments of the present disclosure, each space or protuberance between adjacent magnets of the plurality of permanent magnets (200) is filled using a soft magnetic composite (SMC). Accordingly, by filling the spaces or protuberance between magnets with SMC material, the overall structural 15 integrity and stability of the rotor are enhanced. This ensures that the magnets remain securely positioned and aligned within the rotor, minimizing the risk of displacement or damage during operation. SMC materials also exhibit high permeability and low core loss properties, allowing them to effectively channel and guide magnetic fields. Further, the SMC material also serves as a barrier between 20 adjacent magnets, reducing magnetic interference and enhancing the uniformity of the magnetic field across the rotor. The SMC material filling the protuberances is coated with an insulating material. This insulation layer provides electrical isolation between adjacent magnets, preventing the occurrence of electrical short circuits and ensuring the integrity of the motor's electrical system. By coating the SMC material 25 with insulation, the motor's overall safety and durability are enhanced, making it suitable for a wide range of industrial and automotive applications.
[00052] In one of the embodiments of the present disclosure, the arrangement of the stator components is configured for facilitating the generation of magnetic fields and the rotation of the rotor. The plurality of stator teeth (306) and stator grooves 30 (302) are positioned around the circumference of the stator (300), forming a radial orientation towards the center of the stator (300) and the same establishes the framework for generating magnetic flux and inducing motion in the rotor (100). Further, each stator tooth and groove pair define slots between them, creating a
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spatial arrangement that accommodates the rotation of the rotor (100). These slots serve as channels through which the magnetic fields interact with the rotor (100), exerting torque and inducing rotational motion. The rotor is configured to rotate relative to the stator (300) about an axis of rotation that aligns with the stator center. This alignment ensures that the magnetic interaction between the stator and rotor is 5 optimized for efficient energy conversion and mechanical output. Furthermore, the radial orientation of the stator components and the interposed slots between the stator teeth and rotor contribute to the dynamic functionality of the motor assembly (500). This enables the precise control of magnetic forces and facilitates the transfer of torque from the stator to the rotor, resulting in smooth and reliable operation. 10 Accordingly, by aligning the components along the axis of rotation coinciding with the stator center, the motor assembly achieves a harmonized configuration that maximizes performance and efficiency. [00053] In one of the embodiments of the present disclosure, in the surface permanent magnet motor assembly (500), the arrangement of the
plurality of stator 15 teeth (306) is configured for facilitating efficient energy conversion and magnetic field generation. The plurality of stator teeth (306) is strategically configured to form a V-shaped arrangement with the stator (300), creating an optimal structure for housing the insulated windings or coils. This V-shaped arrangement ensures a precise alignment of the stator components, allowing for effective coupling with 20 the rotor and promoting the generation of magnetic fields. Further, within this V-shaped configuration, the opening formed by the arrangement of the stator teeth serves as a housing for the insulated windings or coils. These windings are positioned to align with the permanent magnets (200) mounted on the rotor (100), enabling the generation of magnetic fields that drive the rotational motion of the 25 motor assembly (500). This ensures efficient magnetic coupling between the stator and rotor, facilitating the conversion of electrical energy into mechanical motion. Furthermore, the arrangement of the plurality of stator teeth (306) and stator grooves (302) is configured to create a sinusoidal magnetic flux distribution within the motor assembly (500). This arrangement of stator elements results in a magnetic 30 field pattern characterized by a sinusoidal waveform, which enhances the efficiency and performance of the motor. By optimizing the distribution of magnetic flux, the motor assembly (500) achieves smoother operation and reduced energy losses, thereby improving overall efficiency and reliability. The plurality of stator slots
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(304) are substantially V-shaped and the plurality of stator slots (304) are configured to receive insulated windings configured on the plurality stator teeth (306).
[00054] In one of the embodiments of the present disclosure, the surface permeant magnet motor assembly (500) incorporates the use of soft magnetic composite 5 (SMC) material in the inner core (102) of the rotor (100). This SMC material offers superior magnetic properties while reducing eddy current losses and improving overall efficiency. To further enhance the insulation and protection of the rotor core, an insulating layer is applied to the SMC material, ensuring optimal performance and longevity of the motor assembly. 10
[00055] In one of the embodiments of the present disclosure, the plurality of stator slots (304), is of substantially V-shaped configuration. The V-shaped slots are positioned and dimensioned to receive insulated windings, which are configured on the plurality of stator teeth (306). This arrangement ensures precise alignment and secure positioning of the insulated windings within the stator structure, optimizing 15 the electromagnetic interaction between the stator and rotor components. By housing the insulated windings within the V-shaped stator slots, the motor assembly achieves a compact and streamlined design, minimizing electromagnetic losses and maximizing power output. Further, the plurality of permanent magnets (200) within the rotor component are arranged circumferentially on the inner core (102) of the 20 rotor (100). This arrangement ensures uniformity and balance in the magnetic field generated by the rotor during operation. By distributing the permanent magnets evenly around the inner core of the rotor, the motor assembly achieves optimal torque production and rotational stability. Furthermore, the circumferential arrangement of permanent magnets contributes to the overall compactness and 25 efficiency of the motor assembly, allowing for seamless integration into various applications across automotive, industrial, and aerospace sectors.
[00056] In one of the embodiments of the present disclosure, within the rotor (100), the plurality of permanent magnets (200) is arranged in a radial pattern within the openings (308) of the inner core (102). This arrangement optimizes the magnetic 30 field distribution, resulting in smoother operation and increased torque production. Accordingly, the motor assembly (500) achieves optimal magnetic coupling between the rotor (100) and stator (300), leading to improved overall performance and efficiency.
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[00057] In one of the embodiments of the present disclosure, to encapsulate and protect the internal components of the motor assembly (500), a casing is employed, enclosing both the stator (300) and the rotor (100). This casing is composed from a non-magnetic material, ensuring minimal interference with the magnetic fields generated by the motor. Accordingly, the motor assembly (500) maintains its 5 efficiency and performance while providing necessary protection against external elements and environmental factors.
[00058] In one of the embodiments of the present disclosure, the rotor (100) features a shaft that extends axially from the inner core (102). This shaft is configured for facilitating the coupling of the motor assembly (500) with external loads or systems. 10 Further, to ensure smooth and reliable rotation, the shaft is equipped with multiple bearings positioned along its length. These bearings provide essential support to the rotor (100), minimizing friction and ensuring smooth rotational motion, thereby enhancing the overall reliability and longevity of the motor assembly (500).
[00059] In one of the embodiments of the present disclosure, the bearings 15 incorporated into the motor assembly configured to provide support for the rotor, enabling smooth rotation with minimal friction. The shaft, extending from the rotor, connects it to the external load or system being driven. Further, lubricated bearings reduce frictional losses, ensuring efficient rotor rotation and overall motor performance. The alignment and balance of the shaft are critical factors in 20 maintaining stable operation and minimizing vibration, thus optimizing motor efficiency.
[00060] Figure 5 illustrates method (600) for constructing the motor assembly (500), the method (600) for constructing a surface permeant magnet motor assembly (500) involves several sequential steps aimed at assembling the various components of 25 the motor to ensure optimal performance and efficiency. Firstly, the method begins with providing (602) a stator (300) with a plurality of stator teeth (306) and stator grooves (302). These components form the stationary part of the motor assembly (500) and are configured for generating the magnetic field necessary for motor assembly (500) operation. Further, the next step in the method (600) providing 30 (604) the rotor (100) with an inner core (102) with a plurality of openings (308) positioned to accommodate plurality of permanent magnets (200). These pluralities of permanent magnets (200) are configured for generating the magnetic field required for motor rotation and power generation. Furthermore, the method
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proceeds to inserting (606) the plurality of permanent magnets (200) into the openings (308) of the rotor (100). This step ensures that the plurality of permanent magnets are securely positioned within the rotor core, optimizing magnetic field distribution and enhancing motor performance. The method also involves filling (608) a protuberance (310) within the inner core (102) of the rotor (100) with a soft 5 magnetic composite (SMC) material. This protuberance is created in areas where permanent magnets are not located, ensuring uniformity and stability within the rotor structure. By filling the protuberance with SMC material, the motor assembly (500) achieves improved magnetic properties and reduced eddy current losses, ultimately enhancing efficiency and performance. 10 [00061] In one of the embodiments of the present disclosure, the introduction of the
plurality of stator grooves (302) on the plurality of stator teeth (306) is configured for mitigating the increase in cogging associated with the added saliency in the motor assembly (500). This approach reduces cogging and torque ripple, resulting in smoother motor assembly (500) operation overall. More specifically, by 15 incorporating an inset magnet configuration, the motor further minimizes cogging and torque irregularities, enhancing operational stability and performance. Accordingly, it not only improves overall motor performance and efficiency but also reduces operational noise and enhances cost-effectiveness.
[00062] The adoption of an inset magnet configuration within the rotor core 20 represents a departure from conventional motor assembly, where external magnets or separate mounting structures are typically employed. Further, the utilization of soft magnetic composite (SMC) material in the vacant volume of the rotor core presents a departure from traditional materials like silicon steel laminations. SMCs offer advantages in terms of flexibility of core shape, enabling more intricate and 25 optimized configuration that contribute to improved motor performance. The integration of the inset magnet configuration optimized magnetic field distribution, and the use of SMC material, along with grooves on the stator teeth, leads to a range of benefits including enhanced efficiency, reduced cogging, and compactness of the motor assembly. 30
[00063] In one of the embodiments of the present disclosure, the magnets are embedded radially within the rotor core, establishing a permanent magnetic field. This configuration enables interaction with the stator's magnetic field, generating rotational force or torque that propels the rotor's motion. By positioning the magnets
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directly within the rotor core, the air gaps between the magnets and the stator are minimized, thereby enhancing magnetic coupling and overall motor efficiency. The arrangement and orientation of these inset magnets is configured for determining the magnetic field distribution and torque characteristics of the motor, influencing its performance. Further, the use of inset magnets allows for a reduction in the net 5 weight of magnets, contributing to the motor's lightweight and efficiency. [00064] In one of the embodiments of the present disclosure, the stator, which surrounds the outer rotor, remains stationery and houses insulated copper windings arranged in a specific pattern. When electric current flows through these windings, a magnetic field is generated. The same ensures alignment between the stator 10 windings and the inset magnets on the rotor. This alignment facilitates the interaction between the magnetic fields produced, resulting in the generation of a driving force that initiates rotor rotation.
[00065] In one of the embodiments of the present disclosure, a motor assembly (500) introduces several features aimed at improving efficiency, power density, and 15 overall performance. More specifically, unlike traditional surface permanent magnet (SPM) motors where magnets are mounted externally on the rotor, this configuration embeds magnets within slots in the rotor core. Further, the vacant spaces left by the magnets are filled with soft magnetic composite (SMC) material, introducing saliency to the permeant magnet machine. This unique configuration 20 reduces the pole angle of the magnets by 30% compared to SPM motors, effectively optimizing magnetic field distribution within the motor. Further, by embedding the magnets within the rotor core and introducing SMC material, this configuration achieves several key advantages. Firstly, it minimizes losses associated with traditional SPM motors, leading to increased efficiency. Secondly, the reduced pole 25 angle and optimized magnetic field distribution contribute to higher power density, allowing the motor to generate more power within a smaller footprint. Moreover, by not pasting the permanent magnets onto the rotor, the configuration simplifies the manufacturing process and enhances the durability of the motor assembly. Furthermore, the utilization of the uneven top surface of the stator grooves (302) to 30 create a non-uniform air gap. This intentional variation in air gap distance between the stator and rotor further enhances motor performance by minimizing cogging torque and improving torque characteristics across different operating conditions.
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[00066] The surface permeant magnet motor assembly (500) presents several advantages over traditional motor configurations. More specifically by embedding magnets securely within the rotor core, the likelihood of magnet detachment or damage is significantly reduced. This not only enhances the motor's durability but also ensures long-term operation without the need for frequent maintenance or 5 replacement of magnets. Further, the integration of magnets within the rotor core allows for a more compact and lightweight motor configuration. This reduction in size and weight not only enhances the motor's portability but also contributes to cost savings in terms of materials, transportation, and installation. Furthermore, the same simplifies the manufacturing process by eliminating the need for separate 10 mounting structures for the magnets. This streamlined approach to manufacturing and assembly reduces production time and costs, making the motor assembly more efficient and cost-effective. Overall, the combination of enhanced durability, reduced size and weight, and simplified manufacturing processes makes the inset magnet motor configuration a compelling choice for various applications across 15 industries, offering improved performance and economic benefits. The surface permeant magnet motor assembly (500) also allows for better acceleration, higher torque, and increased power density, making the motor suitable for demanding applications where performance is crucial.
[00067] The above-described embodiments, and particularly any “preferred” 20 embodiments, are possible examples of implementations and merely set forth for a clear understanding of the principles of the invention. It will be apparent to those skilled in the art that changes in form, connection, and detail may be made therein without departing from the spirit and scope of the invention.
[00068] Non-limiting and non-exhaustive embodiments of the invention are 25 described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. It should be appreciated that the following figures may not be drawn to scale.
[00069] The foregoing disclosure is not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated 30 that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made in form and
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detail without departing from the scope of the present disclosure. Therefore, it is intended that the present invention is not limited to the particular embodiment disclosed, but that the present invention will include all embodiments falling within the scope of the appended claims. [00070] In the foregoing specification, the disclosure has been described with 5 reference to specific embodiments. However, as one skilled in the art will appreciate, various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from scope of the disclosure. Accordingly, this description is to be considered as illustrative and is for the purpose of teaching those skilled in the art the manner of making and using various 10 embodiments of the disclosure. It is to be understood that the forms of disclosure herein shown and described are to be taken as representative embodiments. Equivalent elements, materials, processes or steps may be substituted for those representatively illustrated and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, all as would 15 be apparent to one skilled in the art after having the benefit of this description of the disclosure. Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to 20 the singular is also to be construed to relate to the plural. , Claims:We Claim:
1. A motor assembly (500), the motor assembly (500) comprising:
a stator (300), the stator (300) comprising a plurality of stator teeth (306) and a plurality of stator grooves (302); 5
a rotor (100), the rotor (100) comprising an inner core (102) with a plurality of openings (308); and
a plurality of permanent magnets (200);
wherein the plurality of openings (308) in the inner core (102) of the rotor (100) are configured to accommodate the plurality of permanent magnets (200). 10
2. The motor assembly (500) as claimed in claim 1, wherein the stator (300) comprises a plurality of stator slots (304) defined between the plurality of stator teeth (306), and wherein the plurality of stator slots (304) and the plurality of stator teeth (306) are configured circumferentially, one after another, around a stator core of the stator 15 (300).
3. The motor assembly (500) as claimed in claim 1, wherein the plurality of stator grooves (302) are provided over top surfaces, of the plurality of stator teeth (306), facing towards the inner core (102) of the rotor (100), and wherein dimensions of 20 the plurality of stator grooves (302) are different from each other.
4. The motor assembly (500) as claimed in claim 1, wherein the inner core (102) of the rotor (100) comprises a plurality of protuberance (310) configured between the plurality of openings (308) and protruded towards the stator (300). 25
5. The motor assembly (500) as claimed in claim 4, wherein the plurality of openings (308) and the plurality of protuberance (310) are configured circumferentially and one after another, and wherein the rotor (100) and the inner core (102) of the rotor (100) are composed of a soft magnetic composite (SMC) material. 30
6. The motor assembly (500) as claimed in claim 1, wherein a protuberance between adjacent magnets of the plurality of permanent magnets (200) is filled using a soft
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magnetic composite (SMC) material, and wherein the SMC material is coated with an insulating material.
7.The motor assembly (500) as claimed in claim 2, wherein the plurality of statorslots (304) are substantially V-shaped, and wherein the plurality of stator slots (304)5 are configured to receive insulated windings configured on the plurality stator teeth(306).
8.The motor assembly (500) as claimed in claim 1, wherein the plurality of statorteeth (306) and the plurality of stator grooves (302) are arranged to create a10 sinusoidal magnetic flux distribution within the motor assembly (500) duringoperation of the motor assembly (500).
9.The motor assembly (500) as claimed in claim ,1 wherein the plurality of permanentmagnets (200) are arranged circumferentially on the inner core (102) of the rotor15 (100).
10.A method (600) for constructing a motor assembly (500), the method (600)comprising steps of:20 25
providing (602) a stator (300), the stator (300) comprising a plurality of stator teeth (306) and a plurality of stator grooves (302) provided on the plurality of stator teeth (306); providing (604) a rotor (100), the rotor (100) comprising an inner core (102) with a plurality of openings (308); inserting (606) a plurality of permanent magnets (200) within the plurality of openings (308) of the inner core (102) of the rotor (100); and filling (608) a protuberance between two adjacent permanent magnets of the plurality of permanent magnets (200) with a soft magnetic composite (SMC) material.