WO2023166519A1

WO2023166519A1 - Motor control unit for electric motor and integrated electric motor-motor control unit assembly thereof

Info

Publication number: WO2023166519A1
Application number: PCT/IN2022/051123
Authority: WO
Inventors: Godwin George; Nivethan Latha KANDASAMY; Senthilnathan SUBBIAH
Original assignee: Tvs Motor Company Limited
Priority date: 2022-03-04
Filing date: 2022-12-26
Publication date: 2023-09-07
Also published as: CO2024012081A2

Abstract

The present invention provides motor control unit (100) for an electric motor (202). The motor control unit (100) comprises a frame member (102) attached onto casing (204) of an electric motor (202). Power modules (106) are attached circumferentially onto an inner surface (102a) of the frame member (102). A current splitter (108) being electrically coupled to each of the power modules (106). The current splitter (108) adapted to route current from a power source to each of the power modules (106). Each of power modules (106) is adapted to generate a transformed current based on current received from current splitter (108), the transformed current from each of the power modules (106) being supplied to the electric motor (202) for actuation. Such a construction minimizes voltage drop between motor and motor control unit during current flow, while also ensuring compact layout in applications, such as a vehicle.

Description

TITLE OF INVENTION

Motor Control Unit for Electric Motor and Integrated Electric Motor-Motor Control Unit Assembly Thereof

FIELD OF THE INVENTION

[001] The present invention relates to a motor control unit for an electric motor. More particularly, the present invention relates to an integrated electric motor-motor control unit assembly for a vehicle.

BACKGROUND OF THE INVENTION

[002] A motor control unit typically modulates supply of power or current to an electric motor and controls the operation of the electric motor, based on the state of the motor, for ensuring safe operation of the electric motor. The motor control unit may comprise one or more of an inverter circuit, a DC-DC converter, one or more controllers, etc., capable of being coupled to the electric motor, for supplying power or current to the electric motor.

[003] The circuitry within the motor control unit includes multiple electronic components grouped together to perform functions of step down of the DC voltages supplied by the DC power supply, inversion of the DC power into AC power supply to supply to the electric motor, etc. Conventionally, the motor control unit and the electric motor are housed separately in various applications, such as, a vehicle and are electrically connected via a plurality of electrical connections. As such, a separate motor control unit and a separate electric motor housing has to be accommodated in a vehicle layout. Another challenge pertains to electrical capacity and physical weight contribution of the electric motor and the motor control unit, particularly for a two wheeled vehicle where heavy electrical components are difficult to fit. Further, wired connection between the motor control unit and the electric motor requires current supply to travel through the wiring harness lines for a distance, which results in a voltage drop, while also being expensive and heavy.

[004] In order to overcome the above limitations, attempts have been made to integrate the electric motor and the motor control unit. In the known designs, elements of the motor control unit are fitted on the upper portion of the motor or are mounted radially to a motor casing of the electric motor. However, such a design leads to increase in length between output terminals of power drivers of the motor control unit and input terminals of coils of the electric motor. This further leads to use of more electrical wirings which also results in increase in heat loss caused by an increased electric resistance possessed by the wiring. Additionally, the elongated wiring may result in fitment and noise related problems as well.

[005] As per other known electric motors, the electric motor and the motor control unit are integrated together or are mounted axially. Cooling passages are further provided in a stator of the electric motor and the power driver of the motor control unit, which are thereafter connected through a U-shaped pipe. However, such a construction of the electric motor and the motor control unit requires a separate external cooling system for dissipating the heat generated, which makes the electric motor bulky and heavy, which is undesirable.

[006] Further, as per other known electric motors and motor control units, the motor control unit is attached on a side wall of the electric motor to minimize the wiring length. However, such a motor does not support high capacity inverters which produce high amount of heat. [007] Also in certain axial mounting of the motor control unit with the motor, the motor is mounted on frame of the vehicle and the motor control unit is positioned away from the frame of the vehicle. In such cases, the larger the inverter, greater is the overhang on the side of the vehicle. Moreover, additional material or parts are required for supporting the overhang of the inverter, which makes the device expensive, affects maneuverability of the vehicle and also mileage of the vehicle, which is undesirable.

[008] In view of the above, there is a need for a motor control unit for electric motor and integrated electric motor-motor control unit assembly, which addresses one or more limitations stated above.

SUMMARY OF THE INVENTION

[009] In one aspect, a motor control unit for an electric motor is disclosed. The motor control unit comprises a frame member attached onto a casing of the electric motor. One or more power modules are attached circumferentially onto an inner surface of the frame member. A current splitter is electrically coupled to each of the one or more power modules. The current splitter is adapted to route current from a power source to the each of the one or more power modules. Each of the one or more power modules is adapted to generate a transformed current based on the current received from the current splitter. The transformed current from each of the one or more power modules is supplied to the electric motor for actuation.

[010] In embodiment, each of the one or more power modules is separated from one another.

[011] In an embodiment, the current splitter is a direct current splitter adapted to receive direct current from the power source, the direct current splitter adapted to route direct current to each of the one or more power modules. [012] In an embodiment, each of the one or more power modules is adapted to generate a single-phase alternating current as the transformed current, based on the direct current received from the direct current splitter. The single-phase alternating current from each of the one or more power modules is supplied to the electric motor for actuation.

[013] In an embodiment, the direct current splitter comprises a pair of power terminals adapted to be coupled to the power source for receiving direct current from the power source. The pair of power terminals includes a positive power terminal and a negative power terminal.

[014] In an embodiment, the direct current splitter comprises a positive terminal plate coupled to a positive terminal of the power source via the positive power terminal. The positive terminal plate is defined with at least one positive terminal lead. A negative terminal plate is coupled to a negative terminal of the power source via the negative power terminal. The negative terminal plate is defined with at least one negative terminal lead, wherein each of the at least one positive terminal lead and the at least one negative terminal lead are coupled to positive and negative terminals of the each of the one or more power modules for routing the direct current.

[015] In an embodiment, the direct current splitter comprises a support plate mounted underneath the positive terminal plate and the negative terminal plate. The positive terminal plate, the negative terminal plate and the support plate being laminated by a lamination plate for insulation.

[016] In an embodiment, a control board is mounted over the negative terminal plate and communicably coupled to each of the one or more power modules. The control board is adapted to control operation of the each of the one or more power modules. [017] In an embodiment, a cover member is mounted on a top rim surface of the frame member. The cover member is adapted to enclose the current splitter, each of the one or more power modules and the control board, while exposing a portion of a pair of power terminals.

[018] In an embodiment, a gasket member is provided at an interface of the top rim surface and the cover member. The gasket member is adapted to provide ingress protection to the motor control unit.

[019] In an embodiment, the cover member is provided with a signal connector for connecting with electronic components.

[020] In an embodiment, each of the one or more power modules comprises a phase terminal adapted to be coupled to a phase connector of the electric motor. The phase terminal is adapted to supply the transformed current generated in the each of the one or more power modules to the phase connector for actuation of the electric motor.

[021] In an embodiment, the one or more power modules comprises a first power module, a second power module and a third power module. The first power module, the second power module and the third power module is angularly offset by an angle, when disposed circumferentially along the inner surface of the frame member, wherein the angle is 60 degrees.

[022] In an embodiment, one or more mounting members are defined on an outer surface of the frame member. The one or more mounting members facilitates attachment of the frame member onto the casing of the electric motor.

[023] In an embodiment, a base member is mounted at a central portion of a fore end of the electric motor. The base member encloses a rotary encoder engaged with a shaft of the electric motor and disposed at the fore end for measuring rotation of the electric motor. [024] In an embodiment, the frame member is mounted on a transfer plate provided on a fore end of the electric motor.

[025] In an embodiment, a plurality of fin members are defined on an outer surface of the frame member. The plurality of fin members are adapted to dissipate heat generated within the motor control unit to ambient air.

[026] In another aspect, an integrated electric motor-motor control unit assembly for a vehicle. The assembly comprising the electric motor mounted on a vehicle frame and the motor control unit attached to the electric motor. The motor control unit comprising the frame member attached onto the casing of the electric motor. The one or more power modules are attached circumferentially onto the inner surface of the frame member. The current splitter is electrically coupled to each of the one or more power modules. The current splitter is adapted to route current from the power source of the vehicle to the each of the one or more power modules. Each of the one or more power modules is adapted to generate the transformed current based on the current received from the current splitter. The transformed current from each of the one or more power modules is supplied to the electric motor for actuation.

[027] In an embodiment, the assembly is disposed on the vehicle in a vehicle lateral direction such that the signal connector is pointing away from the vehicle frame.

BRIEF DESCRIPTION OF THE DRAWINGS

[028] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments. Figure 1 is a perspective view of the integrated electric motor-motor control unit assembly, in accordance with an embodiment of the present invention.

Figure 2 is a schematic view of an inverter assembly as a motor control unit, in accordance with an embodiment of the present invention.

Figure 3 is a perspective view of the inverter assembly, in accordance with an embodiment of the present invention.

Figure 4 is an exploded view of a direct current splitter as a current splitter, in accordance with an embodiment of the present invention.

Figure 5 is a schematic view of the direct current splitter coupled to one or more power modules, in accordance with an embodiment of the present invention.

Figure 6 is a sectional view of the one or more power modules mounted to the direct current splitter, in accordance with an embodiment of the present invention.

Figure 7 is an exploded view of the inverter assembly, in accordance with an embodiment of the present invention.

Figure 8 is a sectional view of the inverter assembly, in accordance with an embodiment of the present invention.

Figure 9 is a sectional view of the inverter assembly, in accordance with an embodiment of the present invention.

Figure 10 a sectional view of the inverter assembly, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[029] Various features and embodiments of the present invention here will be discernible from the following further description thereof, set out hereunder. [030] Figure 1 illustrates an integrated electric motor-motor control unit assembly 136, in accordance with an embodiment of the present disclosure. The integrated electric motor-motor control unit assembly 136 may be adapted to be mounted on a vehicle (not shown), which as an example is one of a two-wheeled vehicle or a three-wheeled vehicle. The integrated electric motor-motor control unit assembly 136 is adapted to provide required power or current for operation of the vehicle, while ensuring a compact layout.

[031] The integrated electric motor-motor control unit assembly 136 comprises an electric motor 202 adapted to be mounted onto the vehicle (not shown), via a vehicle frame. The electric motor 202 may be coupled to wheels (not shown) for providing motive force, to drive the vehicle or may be coupled to a crankshaft (not shown) of an engine (not shown). In an embodiment, the electric motor 202 is defined with mounting provisions (not shown) for enabling mounting on the vehicle frame. Further a motor control unit 100 is adapted to be attached to the electric motor 202, to form the integrated electric motor-motor control unit assembly 136. The motor control unit 100 supplies required power or current to the electric motor 202 and/or other electrical or electronic components of the vehicle for operation. The motor control unit 100 is configured to reduce voltage drop in the connections between the motor and the motor control unit, during transfer of power to the electric motor 202.

[032] In the present embodiment, the motor control unit 100 is an inverter assembly, coupled to an Alternating Current (AC) electric motor for suppling alternating current by converting a direct current (DC) received from a power source (not shown). In another embodiment, the motor control unit 100 is a DC-DC converter (not shown) of the vehicle, which is adapted to supply the direct current to the direct current operated electric motor. In an embodiment, the motor control unit 100 is a combination of the Inverter assembly and a DC-DC converter.

[033] Referring to Figures 2 and 3 in conjunction with Figure 1 , the motor control unit 100 is depicted. The motor control unit 100 is adapted to be mounted axially (/.e. along axis A-A’) on the electric motor 202. The motor control unit 100 includes a frame member 102 mounted axially onto a casing 204 of the electric motor 202. That is, the frame member 102 is mounted along the axis A-A’ on the casing 204. In an embodiment, the frame member 102 is mounted on a transfer plate 208 provided on a fore end 204a or a right end of the electric motor 202.

[034] The frame member 102 extends circumferentially along the casing 204 to define a mounting portion 104. On an outer surface 102b (shown in Figure 3) of the frame member 102, one or more mounting members 128 are provided, at strategic locations, for enabling mounting onto the casing 204. In an embodiment, the mounting members 128 are circumferentially offset on the outer surface 102b of the frame member 102. In the present embodiment, the mounting members 128 are grooves that are adapted to receive a fastener 140 (shown in Figure 3) for fastening the frame member 102 onto the casing 204. Accordingly, a threaded hole (not shown) is provided on the casing 204 for receiving the fastener 140. In another embodiment, the mounting members 128 are located between the one or more power modules 106 (as shown in Figure 3), for ensuring stable mounting on the frame member 102.

[035] In an embodiment, the frame member 102 forms a cylindrical structure that extends from a fore end 204a of the casing 204. The hollow portion of the cylindrical structure forms the mounting portion 104 for accommodating components of the motor control unit 100. In an embodiment, the frame member 102 is trapezoidal in crosssection about the axis A-A’. In another embodiment, the frame member 102 is made of a metallic material or a plastic material or a composite material as per design feasibility and requirement.

[036] Further, one or more power modules 106 are attached circumferentially onto an inner surface 102a (shown in Figure 3) of the frame member 102. The one or more power modules 106 are oriented axially to the electric motor 202 for maintaining a compact layout. In an embodiment, axial orientation refers to a width or thickness portion of the one or more power modules 106 being aligned along the axis A-A’ of the electric motor 202. The one or more power modules 106 are mounted on the inner surface 102a such that, each of the one or more power modules 106 is separated from one another. The power modules 106, being rectangular in shape, are positioned in a manner such that the length of the power modules 106 extends along the length of the inner surface 102a of the frame member 102.

[037] In an embodiment, the one or more power modules 106 include a first power module 106a, a second power module 106b and a third power module 106c. Each of the first power module 106a, the second power module 106b and the third power module 106c are angularly offset by an angle (a). In other words, an axis B-B’ of the first power module 106a, an axis C-C’ of the second power module 106b and an axis D-D’ of the third power module 106c are inclined with respect to one another. In an embodiment, the angle (a) is 60 degrees. As such, each of the first power module 106a, the second power module 106b and the third power module 106c form a triangular configuration (as shown in Figure 2). In another embodiment, the angle (a) can be varied between each of the first power module 106a, the second power module 106b and the third power module 106c as per design feasibility and requirement.

[038] Each of the one or more power modules 106 are electrically coupled to a current splitter 108. The current splitter 108 is mounted within the mounting portion 104 of the frame member 102. The current splitter 108 is also coupled to a power source (not shown) for routing current to each of the one or more power modules 106. The current splitter 108 is defined with a pair of power terminals 114 adapted to be coupled to the power source for receiving direct current from the battery module.

[039] In the present embodiment, with the motor control unit 100 being the inverter assembly, the current splitter 108 is a direct current splitter (hereinafter interchangeably referred to as ‘direct current splitter 108’). As such, the direct current splitter 108 is adapted to receive direct current from the power source, split and route the direct current between the one or more power modules 106. Also, the power source is a battery module adapted to supply direct current to the direct current splitter.

[040] In another embodiment, the current splitter 108 can be an alternating current splitter (not shown), as per design feasibility and requirement. Accordingly, the power source can be an alternating current source such as an alternator, for supplying alternating current to the current splitter 108.

[041] Referring to Figure 4, an exploded view of the direct current splitter 108 is depicted. The direct current splitter 108 includes a positive terminal plate 116 coupled to a positive terminal (not shown) of the power source. The positive terminal plate 116 includes a positive power terminal 114a that is adapted to be coupled to the positive terminal of the power source. In an embodiment, the positive power terminal 114a is coupled to the positive terminal of a battery module via conventional coupling means such as clamping, fastening or by contact leads or any other means known in the art as per feasibility and requirement. In an embodiment, the positive power terminal 114a extends upwards from the positive terminal plate 116.

[042] Further, the positive terminal plate 116 is defined with at least one positive terminal lead 116a. The at least one positive terminal lead 116a is adapted to be coupled to each of the one or more power modules 106. In an embodiment, each of the positive power terminal lead 116a is coupled to each of the one or more power modules 106 via fastening onto a positive phase bus bar 146 (shown in Figures 5 and 6) provided in each of the one or more power modules 106. In an embodiment, each of the at least one positive terminal lead 116a extends upwardly from the positive terminal plate 116.

[043] The direct current splitter 108 also includes a negative terminal plate 118 mounted over the positive terminal plate 116 and coupled to a negative terminal (not shown) of the battery module. The negative terminal plate 118 is coupled to the negative terminal of the battery module via a negative power terminal 114b. In an embodiment, the negative power terminal 114b is coupled to the negative terminal of the power source via conventional coupling means such as clamping, fastening or by contact leads or any other means known in the art as per feasibility and requirement. In another embodiment, the negative power terminal 114b extends upwardly from the negative terminal plate 118.

[044] Further, the negative terminal plate 118 is defined with at least one negative terminal lead 118a. The at least one negative terminal lead 118a is adapted to be coupled to each of the one or more power modules 106. In an embodiment, each of the negative power terminal 118a is coupled to each of the one or more power modules 106 via fastening onto a negative phase bus bar 148 (shown in Figures 5 and 6) provided in each of the one or more power modules 106. In an embodiment, each of the at least one negative terminal lead 118a extends downwardly from the positive terminal plate 116. In view of the coupling of the positive terminal lead 116a and the negative terminal lead 118a with the one or more power modules 106, the direct current received from the power source by the direct current splitter 108 is routed to each of the one or more power modules 106. The power modules 106 have combination of electronic components (not shown) for generating the alternating current.

[045] Further, a support plate 120 is mounted underneath the positive terminal plate 116 and the negative terminal plate 118. The support plate 120 is provided to enhance structural rigidity of the direct current splitter 108. Additionally, the support plate, the positive terminal plate and the negative terminal plate are all laminated by a lamination plate 122 for providing insulation. Further, a control board 124 (as shown in Figure 7) mounted axially over the lamination plate 122. The control board 124 may be mounted on the lamination plate 122 via one or more support pegs 142. The one or more support pegs 142 ensure alignment of the control board 124 and also provides adequate support to the control board 124. The control board 124 is communicably coupled to each of the one or more power modules 106, the positive terminal plate 116 and the negative terminal plate 118. The control board 124 includes electronic components such as transistors, processing devices and the like, and is adapted to control operation of each of the one or more power modules 106 in generating AC from the supplied DC.

[046] In an embodiment, the support pegs 142 (for e.g., as shown in Figure 5) may extend upwardly and/or downwardly from the support plate 120 for ensuring alignment of each of the positive terminal plate 1 16, the negative terminal plate 118, the support plate 120 and the control board 124 during assembly. In another embodiment, guide holes 144 (shown in Figure 4) are provided on each of the positive terminal plate 116, the negative terminal plate 118, the lamination plate 122 and the control board 124 which are aligned via the support pegs 142. The direct current splitter 108 is assembled separately by laminating the positive terminal plate 116, the negative terminal plate 118, and the support plate 120 in the lamination plate 122. The assembled direct current splitter 108 is axially mounted in the mounting portion 104 of the motor control unit 100. The support pegs 142 ensure alignment or correct positioning of the terminal plates 116, 118 and the support plate 120 during lamination.

[047] In an embodiment, each of the positive terminal plate 116, the negative terminal plate 118, the support plate 120 and the lamination plate 122 are defined with and dimensions which can be accommodated within the mounting portion 104 of the frame member 102. In the present embodiment, each of the positive terminal plate 116, the negative terminal plate 118, the support plate 120 and the lamination plate 122 are triangular in shape with flat vertices. Accordingly, the shape, dimensions and configuration of each of the positive terminal plate 116, the negative terminal plate 118, the support plate 120 and the lamination plate 122 is selected as per design feasibility and requirement.

[048] In an embodiment, the positive terminal plate 116 includes three positive terminal leads 116a for coupling with each of the first power module 106a, the second power module 106b and the third power module 106c. Also, the positive terminal leads 116a, being upwardly oriented (as shown in Figure 5), engage onto a top surface (not shown) of each of the first power module 106a, the second power module 106b and the third power module 106c via the positive phase bus bar 146 (as shown in Figures 5 and 6).

[049] In an embodiment, the negative terminal plate 118 also includes three negative terminal leads 118a for coupling with each of the first power module 106a, the second power module 106b and the third power module 106c. Also, the negative terminal leads 118a, being downwardly oriented (as shown in Figures 5 and 6), engage onto a lower surface (not shown) of each of the first power module 106a, the second power module 106b and the third power module 106c via the negative phase bus bar 148 (as shown in Figures 5 and 6). [050] Referring to Figure 7 in conjunction with Figures 2-6, each of the one or more power modules 106 is adapted to generate a single-phase alternating current as a transformed current, based on the direct current received from the direct current splitter 108. The single-phase alternating current from each of the one or more power modules 106 is supplied to the electric motor 202 for actuation. In an embodiment, each of the one or more power modules 106 includes a phase terminal 112 (as shown in Figure 8) that is adapted to be coupled to a phase connector 206 of the electric motor 202. The phase terminal 112 is adapted to supply the single-phase alternating current generated in each of the one or more power modules 106 to the phase connector 206 for actuation of the electric motor 202.

[051] In an embodiment, the one or more power modules 106 may also be configured to generate direct current as the transformed current, based on the alternating current received from alternating current splitter. Accordingly, the direct current generated in each of the power modules 106 is supplied to operate the direct current based electric motor.

[052] In the present embodiment, the phase terminal 112 (as shown in Figure 8) is provided for each of the first power module 106a, the second power module 106b and the third power module 106c. Thus, in the present embodiment, three phase terminals 112 are provided in the motor control unit 100. In an embodiment, each of the first power module 106a, the second power module 106b and the third power module 106c produce the single-phase alternating current. As such, a three-phase alternating current is supplied to the electric motor 202 via the phase terminals 112 from all the three power modules 106 together.

[053] Further, the motor control unit 100 includes a cover member 126 mounted on a top rim surface 102c of the frame member 102. The cover member 126 is adapted to enclose the current splitter 108, each of the one or more power modules 106 and the control board 124. Thus, the cover member 126 encloses the components mounted within the frame member 102.

[054] In an embodiment, upon mounting of each of the positive terminal plate 116, the negative terminal plate 118 and the support plate 120, the power terminals 114 themselves act as guides for facilitating alignment, during mounting of the cover member 126 and the signal connector 134 (for e.g., as shown in Figure 9). In an embodiment, the signal connector 134 is provided on surface of the cover member 126 (as shown in Figure 1 ). In another embodiment, the signal connector 134 may be provided on an intermediate plate 150 (as shown in Figure 7) mounted below the cover member 126. In an embodiment, the signal connector 134 may be a socket type connector known in the art for coupling two electrical components.

[055] In an embodiment, a gasket member 138 (as shown in Figure 8) is provided at an interface of the top rim surface 102c and the cover member 126. The gasket member 138 is adapted to provide ingress protection to the inverter motor control unit 100. In an embodiment, the gasket member 138 is made of a non-metallic material or a metallic material or a composite material as per design feasibility and requirement. In another embodiment, the cover member 126 is provided with a signal connector 134. In an embodiment, the integrated electric motor-motor control unit assembly 136 is disposed on the vehicle such that, the signal connector 134 is pointing away from the vehicle frame. Such a construction facilitates engagement and disengagement of the wiring harness with the signal connector 134.

[056] Referring to Figures 9 and 10, the motor control unit 100 includes a base member 130 mounted at a central portion of the fore end 204a of the electric motor 202. The base member 130 encloses a rotary encoder 132 for measuring rotational speed of the electric motor 202. The base member 130 is mounted on the transfer plate 208. In the space between the base member 130 and the transfer plate 208, the rotary encoder 132 is enclosed. Further, a plurality of fin members 110 are defined on the outer surface 102b of the frame member 102. The plurality of fin members 110 adapted to dissipate heat generated within the inverter motor control unit 100 to ambient air. Thus, mitigating the need for a separate cooling system in the vehicle. In an embodiment, the plurality of fin members 110 extend axially along the axis A-A’ of the casing 202, for ensuring that maximum surface area is available for contact with ambient air, ensuring optimum or maximum cooling efficiency. In another embodiment, the orientation, inclination or construction of the plurality of fin members 110 on the frame member 102 can be selected as per design feasibility and requirement. In another embodiment, the plurality of fin members 110 are made of metallic material for ensuring maximum heat dissipation with the ambient air. In an embodiment, the plurality of fin members 110 are provided in regions where the one or more power modules 106 are mounted. Such a construction allows localized dissipation of heat from the one or more power modules 106 using natural convection.

[057] In an embodiment, the integrated electric motor-motor control unit assembly 136 may be adapted to be mounted on an appliance which may employ electric motor 202 for its operation such as a pump, a generator and the like. Accordingly, the motor control unit 100 may also be mounted on any electric motor 202 which is mounted on the vehicle or on the appliance, as per feasibility and requirement. In an operational embodiment, the direct current splitter 108 receives power supply or direct current from the battery source. According to the power requirements computed by the control board 124, the control board 124 operates the direct current splitter 108 to supply the direct current received from the battery source to the one or more power modules 106. The one or more power modules 106 generate the alternating current, which is routed to the electric motor 202 via the phase terminal 112 for actuation. In an embodiment, the control board 124 operates the direct current splitter 108 to supply the direct current to each of the first power module 106a, the second power module 106b and the third power module 106c, so that three-phase alternating current is generated. The three- phase alternating current is thereafter routed to the electric motor 202 via the phase terminals 112 for actuation.

[058] The claimed invention as discussed above is not routine, conventional, or well understood in the art, as the claimed aspects enable the following solutions to the existing problems in conventional technologies. Specifically, the claimed aspects of axial integration of the motor control unit 100 with the electric motor 202, makes the integrated electric motor-motor control unit assembly 136 modular and compact with minimal or negligible voltage drop across components during current flow, while providing technical solution to the technical problem. Also, due to compact layout of the motor control unit 100 on the electric motor 202, the overhang of the motor control unit 100 in the vehicle is reduced, thereby mitigating additional parts required for supporting the integrated electric motor-motor control unit assembly 136. Moreover, the control board 124 is mounted over the current splitter 108, thereby mitigating requirement of additional space for the control board 124 in the vehicle. Additionally, plurality of fin members 110 are provided on the outer surface 102b of the frame member 102 which ensure heat dissipation due to flow of ambient air and thus mitigating the need for a separate cooling system. As such, the number of components in the vehicle is reduced, thereby making the vehicle lighter and consequently, improving performance of the vehicle. [059] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.

Reference numerals

100 - Motor control unit

102 - Frame member

102a - Inner surface of the frame member

102b - Outer surface of the frame member

104 - Mounting portion in the frame member

106 - One or more power modules

106a - First power module

106b - Second power module

106c - Third power module

108 - Current splitter

110 - Plurality of fin members

112 - Phase terminal

114 - Power terminals

114a - Positive power terminal

114b - Negative power terminal

116 - Positive terminal plate

116a - Positive terminal lead

118 - Negative terminal plate

118a - Negative terminal lead

120 - Support plate

122 - Lamination plate

124 - Control board

126 - Cover member

128 - Mounting member

130 - Base member

132 - Rotary encoder Signal connector

Integrated electric motor-motor control unit assembly

Gasket member

Fastener

Support pegs

Guide holes

Positive phase bus bar

Negative phase bus bar

Intermediate plate

Electric motor

Casing of electric motor

Phase terminal

Transfer plate

Claims

CLAIMS:

1. A motor control unit (100) for an electric motor (202), the motor control unit (100) comprising: a frame member (102) attached onto a casing (204) of the electric motor (202); one or more power modules (106) attached circumferentially onto an inner surface (102a) of the frame member (102); a current splitter (108) being electrically coupled to each of the one or more power modules (106), the current splitter (108) adapted to route current from a power source to the each of the one or more power modules (106), wherein each of the one or more power modules (106) is adapted to generate a transformed current based on the current received from the current splitter (108), the transformed current from each of the one or more power modules (106) being supplied to the electric motor (202) for actuation.

2. The motor control unit (100) as claimed in claim 1 , wherein each of the one or more power modules (106) is separated from one another.

3. The motor control unit (100) as claimed in claim 1 , wherein the current splitter (108) is a direct current splitter adapted to receive direct current from the power source, the direct current splitter adapted to route direct current to each of the one or more power modules (106).

4. The motor control unit (100) as claimed in claim 3, wherein each of the one or more power modules (106) is adapted to generate a single-phase alternating current as the transformed current, based on the direct current received from the direct current splitter, the single-phase alternating current from each of the one or more power modules (106) being supplied to the electric motor (202) for actuation.

5. The motor control unit (100) as claimed in claim 3, wherein the direct current splitter comprises a pair of power terminals (114) adapted to be coupled to the power source for receiving direct current from the power source, the pair of power terminals (114) including a positive power terminal (114a) and a negative power terminal (114b).

6. The motor control unit (100) as claimed in claim 5, wherein the direct current splitter comprises: a positive terminal plate (116) coupled to a positive terminal of the power source via the positive power terminal (114a), the positive terminal plate (116) defined with at least one positive terminal lead (116a); and a negative terminal plate (118) coupled to a negative terminal of the power source via the negative power terminal (114b), the negative terminal plate (118) defined with at least one negative terminal lead (118a), wherein the each of the at least one positive terminal lead (116a) and the at least one negative terminal lead (118a) is coupled to positive and negative terminals of the each of the one or more power modules (106) for routing the direct current.

7. The motor control unit (100) as claimed in claim 6, wherein the direct current splitter comprises: a support plate (120) mounted underneath the positive terminal plate (116) and the negative terminal plate (118), and said positive terminal plate (116), said negative terminal plate (118), and said support plate (120) being laminated by a lamination plate (122) for insulation.

8. The motor control unit (100) as claimed in claim 7 comprising a control board (124) mounted over the negative terminal plate (118) and communicably coupled to each of the one or more power modules (106), the control board (124) adapted to control operation of the each of the one or more power modules (106).

9. The motor control unit (100) as claimed in claim 1 , comprising a cover member (126) mounted on a top rim surface (102c) of the frame member (102), the cover member (126) adapted to enclose the current splitter (108), the each of the one or more power modules (106) and a control board (124), while exposing a portion of a pair of power terminals (114).

10. The motor control unit (100) as claimed in claim 9 comprising a gasket member (138) provided at an interface of the top rim surface (102c) and the cover member (126), the gasket member (138) adapted to provide ingress protection to the motor control unit (100).

11 . The motor control unit (100) as claimed in claim 9, wherein the cover member (126) is provided with a signal connector (134) for connecting with electronic components.

12. The motor control unit (100) as claimed in claim 1 , wherein each of the one or more power modules (106) comprises a phase terminal (112) adapted to be coupled to a phase connector (206) of the electric motor (202), the phase terminal (112) adapted to supply the transformed current generated in the each of the one or more power modules (106) to the phase connector (206) for actuation of the electric motor (202).

13. The motor control unit (100) as claimed in claim 1 , wherein the one or more power modules (106) comprises a first power module (106a), a second power module (106b) and a third power module (106c), the first power module (106a), the second power module (106b) and the third power module (106c) being angularly offset by an angle (a), when disposed circumferentially along the inner surface of the frame member, wherein the angle is 60 degrees.

14. The motor control unit (100) as claimed in claim 1 comprising one or more mounting members (128) defined on an outer surface (102b) of the frame member (102), the one or more mounting members (128) facilitate attachment of the frame member (102) onto the casing (204) of the electric motor (202).

15. The motor control unit (100) as claimed in claim 1 comprising a base member (130) mounted at a central portion of a fore end (204a) of the electric motor (202), the base member (130) enclosing a rotary encoder (132) engaged with a shaft of the electric motor and disposed at the fore end for measuring rotation of the electric motor (202).

16. The motor control unit (100) as claimed in claim 1 , wherein the frame member (102) is mounted on a transfer plate (208) provided on a fore end (204a) of the electric motor (202).

17. The motor control unit (100) as claimed in claim 1 comprising a plurality of fin members (110) defined on an outer surface (102b) of the frame member (102), the plurality of fin members (110) adapted to dissipate heat generated within the motor control unit (100) to ambient air.

18. An integrated electric motor- motor control unit assembly (136) for a vehicle, the assembly (136) comprising: an electric motor (202) mounted on a vehicle frame; and a motor control unit (100) attached to the electric motor (202), the motor control unit (100) comprising: a frame member (102) attached onto a casing (204) of the electric motor (202); one or more power modules (106) attached circumferentially onto an inner surface (102a) of the frame member (102); a current splitter (108) being electrically coupled to each of the one or more power modules (106), the current splitter (108) adapted to route current from a power source of the vehicle to the each of the one or more power modules (106), wherein each of the one or more power modules (106) is adapted to generate a transformed current based on the current received from the current splitter (108), the transformed current from each of the one or more power modules (106) being supplied to the electric motor (202) for actuation.

19. The assembly (136) as claimed in claim 18, wherein each of the one or more power modules (106) is separated from one another.

20. The assembly (136) as claimed in claim 18, wherein the current splitter (108) is a direct current splitter adapted to receive direct current from the power source, the direct current splitter adapted to route direct current to each of the one or more power modules (106).

21 . The assembly (136) as claimed in claim 20, wherein each of the one or more power modules (106) is adapted to generate a single-phase alternating current as the transformed current, based on the direct current received from the direct current splitter, the single-phase alternating current from each of the one or more power modules (106) being supplied to the electric motor (202) for actuation.

22. The assembly (136) as claimed in claim 20, wherein the direct current splitter comprises a pair of power terminals (114) adapted to be coupled to the power source in the vehicle for receiving direct current from the power source, the pair of power terminals (114) including a positive power terminal (114a) and a negative power terminal (114b).

23. The assembly (136) as claimed in claim 22, wherein the direct current splitter comprises: a positive terminal plate (116) coupled to a positive terminal of the power source via the positive power terminal (114a), the positive terminal plate (116) defined with at least one positive terminal lead (116a); and a negative terminal plate (118) coupled to a negative terminal of the power source via the negative power terminal (114b), the negative terminal plate (118) defined with at least one negative terminal lead (118a), wherein the each of the at least one positive terminal lead (116a) and the at least one negative terminal lead (118a) is coupled to positive and negative terminals of the each of the one or more power modules (106) for routing the direct current.

24. The assembly (136) as claimed in claim 23, wherein the direct current splitter comprises: a support plate (120) mounted underneath the positive terminal plate (116) and the negative terminal plate (118), and said positive terminal plate, said negative terminal plate, and said support plate being laminated by a lamination plate (122) for insulation.

25. The assembly (136) as claimed in claim 24 comprising a control board (124) mounted over the negative terminal plate (118) and communicably coupled to each of the one or more power modules (106), the control board (124) adapted to control operation of the each of the one or more power modules (106).

26. The assembly (136) as claimed in claim 18, comprising a cover member (126) mounted on a top rim surface (102c) of the frame member (102), the cover member (126) adapted to enclose the current splitter (108), the each of the one or more power modules (106) and a control board (124), while exposing a portion of a pair of power terminals (114).

27. The assembly (136) as claimed in claim 26 comprising a gasket member (138) provided at an interface of the top rim surface (102c) and the cover member (126), the gasket member (138) adapted to provide ingress protection to the motor control unit (100).

28. The assembly (136) as claimed in claim 26, wherein the cover member (126) is provided with a signal connector (134) for connecting with electronic components of the vehicle.

29. The assembly (136) as claimed in claim 18, wherein the assembly (136) being disposed on the vehicle in a vehicle lateral direction such that a signal connector (134) pointing away from the vehicle frame.

30. The assembly (136) as claimed in claim 18, wherein each of the one or more power modules (106) comprises a phase terminal (112) adapted to be coupled to a phase connector (206) of the electric motor (202), the phase terminal (112) adapted to supply the transformed current generated in the each of the one or more power modules (106) to the phase connector (206) for actuation of the electric motor (202).

31. The assembly (136) as claimed in claim 18, wherein the one or more power modules (106) comprises a first power module (106a), a second power module (106b) and a third power module (106c), the first power module (106a), the second power module (106b) and the third power module (106c) being angularly offset by an angle (a), when disposed circumferentially along the inner surface of the frame member, wherein the angle is 60 degrees.

32. The assembly (136) as claimed in claim 18 comprising one or more mounting members (128) defined on an outer surface (102b) of the frame member (102), the one or more mounting members (128) facilitate attachment of the frame member (102) onto the casing (204) of the electric motor (202).

33. The assembly (136) as claimed in claim 18 comprising a base member (130) mounted at a central portion of a fore end (204a) of the electric motor (202), the base member (130) enclosing a rotary encoder (132) engaged with a shaft of the electric motor and disposed at the fore end for measuring rotation of the electric motor (202).

34. The assembly (136) as claimed in claim 18, wherein the frame member (102) is mounted on a transfer plate (208) provided on a fore end (204a) of the electric motor (202). 35. The assembly (136) as claimed in claim 18 comprising a plurality of fin members

(110) defined on an outer surface (102b) of the frame member (102), the plurality of fin members (110) adapted to dissipate heat generated within the motor control unit (100) to ambient air.