Description:LIQUID COOLED, LIGHT WEIGHT, HIGH POWER, HIGH TORQUE INDUCTION MOTOR FOR ELECTRIC VEHICLES

:
[001] FIELD OF THE INVENTION :
The instant disclosure pertains to the domain of electric vehicle (EV) propulsion systems, focusing specifically on a cutting-edge liquid-cooled 5 lightweight high-power induction motor and its corresponding direct current (DC) inverter. This innovation has been crafted with the explicit intent of revolutionizing the landscape of electric propulsion in vehicles, ensuring not only efficiency and effectiveness but also imparting a remarkable degree of versatility. The invention stands out by prioritizing enhanced efficiency, a broad spectrum of power and torque 10 generation capabilities and remarkable adaptability to a diverse array of input voltages.
BACKGROUND OF THE INVENTION :
[002]
The advent of automobiles, catalyzed by the invention of the internal combustion engine, has undeniably become an indispensable facet of human life. 15 However, this convenience comes at a price of environmental pollution and the excessive depletion of energy resources. In response to these challenges, the automotive industry has witnessed the emergence of electric vehicles (EVs), hydrogen fuel cell vehicles, and hybrid vehicles combining various propulsion technologies. 20
[003]
Electric vehicles, powered predominantly by AC or DC motors utilizing battery energy, are broadly categorized into battery-only electric vehicles and hybrid electric vehicles. The latter, functioning by employing an internal combustion engine to generate electricity for recharging the battery, introduces a dynamic approach to sustainable transportation. 25
[004]
Hybrid electric vehicles exhibit further classification into series and parallel configurations. In the series method, mechanical energy from the engine is converted into electrical energy through a generator, providing continuous power to a battery or motor. Conversely, the parallel method allows the vehicle to be driven solely by
3
the engine or the battery, depending on driving conditions. This innovation aims to
enhance the mileage of existing electric vehicles by incorporating an engine and a generator, presenting a versatile solution adaptable to varied driving scenarios.
[005]
In recent times, advancements in motor and control technology have yielded high-power, compact, and highly efficient systems. The transition from DC to AC 5 motors has significantly improved output and EV power performance, bringing acceleration and top speed capabilities on par with traditional gasoline-powered cars. The development of lightweight, high-output motors has resulted in a reduction of payload and volume, thereby addressing key concerns in electric vehicle design. The advancement in lightweight, high-output motor technology has significantly 10 mitigated concerns related to payload and volume in electric vehicle design. This development allows for a more efficient use of space and a reduction in overall weight, contributing to enhanced performance and addressing crucial design considerations in the realm of electric vehicles.
[006]
The primary focus of the invention lies in the design of a motor specifically 15 tailored for electric vehicle drivetrains. Emphasis is placed on achieving a delicate balance between lightweight construction to minimize the Gross Vehicle Weight (GVW) of the EV and the capacity to generate high torque and speed. Extensive market research revealed a gap in the domestic market, prompting Indian EV manufacturers to rely on imports for such specialized motors. 20
[007]
One of the pivotal innovations within this invention is the incorporation of an effective pressured liquid cooling system, aiming to reduce the overall mass of the motor body. This cooling mechanism encompasses the stator body, shaft, flanges, and bearings, contributing to the compactness and reduced weight of the motor.
[008]
Furthermore, market analysis highlighted a prevalent issue concerning the 25 suitability of domestically available motors for specific input voltage conditions. Acknowledging the varied voltage requirements of different Original Equipment Manufacturers (OEMs), the invention addresses this concern by designing the motor to accommodate a wide range of input voltages, enhancing its versatility.
4
[009]
The motor is meticulously engineered to ensure high efficiency across a broad spectrum of output speeds and torques, even under fluctuating input voltage conditions. This unique characteristic directly impacts the mileage/range of electric vehicles, setting the invention apart from existing motors in the domestic market.
[0010]
Strategic considerations during the motor design process, such as the selection 5 of core diameter and length, adhere to predefined norms to maintain optimal electric and magnetic characteristics. The culmination of these key design features positions this motor as a singular and unparalleled solution for integration into electric vehicle drivetrains, reflecting a pioneering step in advancing the sustainability of electric transportation. 10
OBJECTIVES OF THE INVENTION :
[0011]
The objectives of the invention, as inferred from simulation results, are as follows:
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Technical Compliance:
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Ensure that the designed motor aligns with and satisfies established 15 technical norms and standards governing the electromagnetics of motor design.
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Simulation Validation:
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Conduct rigorous simulations to validate the motor's performance under diverse operating conditions. 20
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Evaluate key simulation outputs, including developed torque, speed, efficiency, and temperature rise profile, to confirm adherence to predetermined technical specifications.
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Optimal Performance:
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Attain optimal motor performance characterized by a harmonious blend 25 of torque, speed, and efficiency, as indicated by simulation results.
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Thermal Management:
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Implement effective thermal management strategies to control temperature rise during motor operation, ensuring sustained performance within acceptable temperature limits. 30
5
•
Weight and Volume Reduction:
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Design the motor with a specific emphasis on achieving low weight and volume characteristics to meet the demands of electric vehicle (EV) applications.
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Aim to contribute to overall weight reduction in EVs, enhancing their 5 efficiency and range.
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Electric Vehicle Suitability:
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Demonstrate that the motor is well-suited for integration into electric vehicles, considering the unique requirements and constraints of EV drivetrains. 10
•
Versatility Across Input Voltage Range:
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Address the challenge of varying input voltage conditions by designing the motor to be adaptable to a wide range of input voltages.
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Enhance the versatility of the motor, making it compatible with different electric vehicle models and charging infrastructures. 15
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Market Gap Fill:
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Recognize and address gaps in the domestic market by providing a motor solution that meets the specific needs of electric vehicle manufacturers.
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Aim to reduce reliance on imports by offering a locally developed motor that matches or exceeds the capabilities of imported alternatives. 20
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Elevated Efficiency Throughout Operating Range:
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Ensure that the motor maintains high efficiency across a broad range of output speeds and torques, directly impacting the overall mileage range of electric vehicles.
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Innovation in Motor Design: 25
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Introduce innovative design elements that distinguish the motor from existing solutions, showcasing advancements in electromagnetics, materials science, and thermal engineering.
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Position the motor as a pioneering contribution to the field of electric vehicle propulsion, emphasizing advancements that can potentially 30 redefine motor design standards.
6
[0012]
These objectives collectively underscore the intention to create a motor that not only meets technical benchmarks but also addresses specific challenges in the electric vehicle industry, contributing to the sustainable evolution of electric transportation.
SUMMARY OF THE INVENTION : 5
[0013]
The invention is driven by several key considerations and features, as detailed below:
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Effective Pressured Liquid Cooling:
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The primary goal is to reduce the total mass of the motor body through the implementation of an effective pressured liquid cooling system. 10
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Components such as the Stator body, shaft, both side flanges, including bearings, have been strategically considered for cooling to achieve a compact and lightweight motor design.
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Cooling of motor flanges for longer shelf life of bearing.
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Compact and Lightweight Design: 15
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The integration of pressured liquid cooling serves the dual purpose of enhancing efficiency while concurrently minimizing the overall weight of the motor.
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This design philosophy is crucial for electric vehicle applications, where a reduction in motor weight directly contributes to improved efficiency 20 and range.
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High Efficiency Across a Wide Range:
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The motor is meticulously designed to ensure high efficiency across a broad output speed and torque range.
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This characteristic is particularly essential for electric vehicles, directly 25 influencing the mileage range and overall performance of the vehicle under varying driving conditions.
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Versatility in Input Voltage:
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The motor is engineered to operate efficiently with a wide range of input voltages, addressing the diverse needs of electric vehicle applications. 30
7
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The adaptability to varying input voltages contributes to the versatility of the motor, making it compatible with different electric vehicle models and charging infrastructures.
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Motor Core Diameter and Length Selections:
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Specific calculations are incorporated in the motor design concerning the 5 selection of motor core diameter and length.
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These calculations aim to maintain the electric and magnetic characteristics of the motor well within predefined norms, ensuring optimal performance and reliability.
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Three-Phase Induction Motor for Four-Wheeler EVs: 10
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Considering the application in four-wheeler electric vehicles, the motor is designed as a three-phase induction motor.
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The speed of the motor can be precisely controlled using a variable frequency inverter, allowing for versatile and efficient performance.
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Variable Speed Control up to 15000 RPM: 15
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The motor is designed to operate within a wide speed range, with the ability to be controlled by a variable frequency inverter.
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The motor's speed can be increased up to 15000 RPM, providing flexibility and adaptability to different driving conditions and requirements. 20
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Dual Input Voltage Capability:
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Specifically tailored for a four-wheeler electric vehicle application, the motor is designed to operate with dual input voltages: 800VDC and 400VDC.
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The motor's maximum torque remains consistent at 501Nm, irrespective 25 of the applied input voltage, ensuring uniform and reliable performance.
[0014]
In essence, the design philosophy behind this motor encompasses effective cooling, compactness, high efficiency across diverse operating conditions, and adaptability to varying input voltages-critical features that position it as an ideal solution for electric vehicle propulsion, particularly in the context of four-wheeler 30 applications.
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[0015]
Innovative motor under this invention is versatile and can be customized for application in Hydrogen Electric Vehicles (HEVs), wherein the primary source of propulsion is derived from the generation of electricity through hydrogen fuel cells. This adaptation allows for the seamless integration of our motor technology into the HEV framework, enabling efficient and sustainable power generation for the 5 vehicle's electric propulsion system.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING(S) :
[0016]
One way in which the invention may be performed will now be described by way of example with reference to the accompanying drawings. A textual representation of the drawings described herein: 10
[0017]
Sl No. 1: Rendered 3D Drawing of Designed Motor
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This drawing illustrates the overall design of the motor. The drive end side motor flange is depicted as a general representation, emphasizing its adaptability to suit specific requirements and match OEMs' gearbox flanges. 15
[0018]
Sl No. 2 & 3: Design Data
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Stator diameter: 248mm
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Core length: 140mm
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Stator slots: 54 Nos.
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Rotor slots: 42 Nos. 20
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Core material: M250-45A grade CRNO sheet steel
[0019]
Sl No. 4 & 5: Shaft Design
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Drawing of the shaft, including its dimensions and cooling hole.
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Depicts the shaft fitted in the rotor core, fixed with copper rotor bars and end rings. 25
[0020]
Sl No. 6: DE Side End Shield
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Illustrates the drive end side end shield with cooling paths.
9
[0021]
Sl No. 7: NDE Side End Shield (Inside Details)
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Provides detailed views of the inside of the non-drive end side end shield, highlighting different subparts of this component.
[0022]
Sl No. 8: NDE Side End Shield (Outer Side Details)
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Shows the outer side details of the non-drive end side end shield. 5
[0023]
Sl No. 9: Motor Body without End Shields and Rotor
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Illustrates the motor body without end shields and rotor, showcasing cooling paths. The cooling circuit is completed when the rotor with the shaft is inserted inside the motor body, and both side end flanges are fitted. 10
[0024]
Sl No. 10: Stator Core and Rotor Core
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Depicts the stator core without winding and the rotor core with copper bars and end rings inserted inside the stator core.
[0025]
Sl No. 11: Calculated Dimensions of Motor without End Covers
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Shows the calculated dimensions of the motor without end covers fitted. 15
DETAILED DESCRIPTION OF INVENTION WITH REFERENCE TO THE DRAWINGS OF THE PREFERRED EMBODIMENTS
[0026]
In this document, a comprehensive array of systems, devices, and techniques are explicated, collectively defining the Liquid Cooled Induction Motor for Electric Vehicles. The primary aim is to realize a motor design that embodies characteristics 20 such as light weight, high power, high torque, and the capability to operate efficiently across a wide range of input voltages. The document meticulously details the innovative features and methodologies incorporated into the design, elucidating the intricate mechanisms that contribute to the attainment of these key objectives. This Liquid Cooled Induction Motor stands as a testament to advancements in 25 electric vehicle propulsion, showcasing a balance of performance and adaptability crucial for the evolving landscape of electric transportation.
10
[0027]
In the drawing listed as Sl No. 1, a rendered 3D representation of the designed motor is depicted. Notably, the drive end side motor flange is presented as a generalized component, designed to be adaptable and customizable to meet specific requirements. This flexibility allows for tailoring the motor flange to seamlessly match the specifications of Original Equipment Manufacturers (OEMs), ensuring 5 compatibility with various gearbox flanges. The rendered 3D drawing serves as a visual guide to showcase the overall design and modifiability of the drive end side motor flange, emphasizing its versatility in accommodating diverse gearbox configurations.
[0028]
In the drawings marked as Sl No. 2 and 3, the design data for the motor is 10 presented. The specifications include a stator core diameter of 248mm, a core length of 140mm, and the incorporation of 54 slots for the stator and 42 slots for the rotor. The chosen core material is M250-45A grade Cold Rolled Non-Oriented (CRNO) sheet steel. These details provide a foundational understanding of the physical dimensions and materials used in the stator and rotor core construction, essential 15 aspects that contribute to the overall performance and efficiency of the motor.
[0029]
In the drawings identified as Sl No. 4 and 5, the focus is on the motor's shaft. These drawings provide detailed insights into the dimensions of the shaft, its structural features, and the incorporation of a cooling hole. Additionally, the sequence concludes with a representation of the shaft being fitted into the rotor core, 20 secured in place by copper rotor bars and end rings. This series of drawings serves to illustrate the intricacies of the shaft design, emphasizing its dimensions, cooling mechanism, and the integral role it plays in connecting with and supporting the rotor core components, including the copper rotor bars and end rings.
[0030]
In the set of drawings specified as Sl No. 6, the focus is on the Drive End (DE) 25 side end shield. These drawings delineate the design and cooling paths incorporated in this particular component. Moving forward, Sl No. 7 presents a comprehensive overview of the internal details of the Non-Drive End (NDE) side end shield, providing a breakdown of various subparts within this crucial component. Finally, Sl No. 8 delves into the external aspects, presenting detailed outer side features of 30 the NDE side end shield. Collectively, these drawings offer a holistic understanding
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of the design, internal structure, and external characteristics of both the DE and NDE
side end shields, critical components contributing to the overall functionality and cooling efficiency of the motor.
[0031]
The drawing marked as Sl No. 9 provides a depiction of the motor body without the end shields and rotor. In this illustration, the cooling paths within the motor body 5 are clearly showcased. The design of the cooling circuit within the motor body becomes integral to the overall functionality, and it is emphasized that the cooling circuit achieves completeness when the rotor, along with the shaft, is inserted into the motor body. Additionally, the fitting of both side end flanges completes the assembly, ensuring that the cooling system is fully integrated and capable of 10 effectively managing the thermal aspects of the motor during operation. This drawing serves as a visual guide to understanding the internal structure and cooling mechanisms within the motor body.
[0032]
The drawing assigned the number Sl No. 10 illustrates the stator core without winding, with the rotor core featuring inserted copper bars and end rings inside the 15 stator core. This depiction offers a clear view of the internal components and their arrangement within the motor assembly. The subsequent drawing in the series, Sl No. 11, provides the calculated dimensions of the motor in this configuration, specifically without the end covers fitted. These dimensions serve as a crucial reference point for understanding the spatial characteristics of the motor at this stage 20 of assembly, contributing to the overall comprehension of the motor's design and internal arrangement.
[0033]
The motor design incorporates a double layer lap winding for the stator, emphasizing a configuration that enhances efficiency and performance. For the rotor, solid copper is chosen for both the rotor bars and end rings, a selection that 25 ensures robust electrical conductivity and durability. The detailed material specifications for all components involved in this motor design are comprehensively outlined in a document listed as Sl No. 12 in the drawing list. This document serves as a critical reference, providing exhaustive information about the specific materials used, contributing to the precision and reliability of the motor's construction. 30
12
[0034]
The motor design incorporates a double layer lap winding for the stator, and the rotor bars and end rings are constructed using solid copper. The detailed material specifications for all components involved in the motor design are provided in a document listed as Sl No. 12 in the drawing list. Magnetic loading is addressed with an average flux density of 0.65 Tesla. The design parameters include a 440V AC 5 base input voltage for the motor and a peak current of 270A at 15000 RPM. The stator winding wire size, winding pattern, and slot fill factor are selected accordingly. The motor cooling system is intricate, featuring complex cooling paths within the motor body, end flanges, and shaft hole. This system will be cooled by an external pressured liquid coolant recirculating system, with a cooling pipe considered in the 10 NDE side flange to supply coolant inside the shaft. High-speed bearings in both the DE and NDE sides of the shaft will also receive equal cooling with the end shields and shaft. For motor speed measurement, a toothed pinion and provision for a sensor are considered in the NDE side for generating pulses. The total weight of the core, including stator winding, rotor copper bars, and end rings, is approximately 58 kgs, 15 with the motor body and end covers envisaged to be made from aluminum. The calculated designed specific electrical loading of the motor is approximately 77000 Am, and the designed output from the motor is around 300 kW at a power factor of 0.86. The performance of the designed motor has been rigorously assessed through multiple simulations. 20
[0035]
The simulation results with an 800V DC input system provide valuable insights into the performance and thermal characteristics of the motor. The observations, as indicated in Sl No. 13 and Sl No. 14 of the drawing list, are summarized below:
[0036]
Simulation Results with 800V DC Input:
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Torque Development: 25
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Rotor shaft developed a torque of 501 Nm.
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System Efficiency:
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System efficiency noted up to 96%.
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Motor Speed:
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Motor developed a speed of up to 14930 RPM. 30
13
•
Torque Characteristics:
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Maximum torque of 501 Nm observed up to 2000 RPM and gradually decreases with an increase in speed.
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Maintains a torque of 40-50 Nm till the end of the simulation speed at 12500 RPM. 5
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Efficiency at Different Speeds:
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Maximum efficiency (approximately 96%) observed within the speed range of 3000 RPM to 8000 RPM.
[0037]
Temperature Rise Simulation (Without Cooling System):
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Motor Housing: 10
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Average temperature of the motor housing is 192 °C.
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Rotor:
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Average temperature of the rotor is 207 °C.
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Stator:
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Average temperature of the stator is 202 °C. 15
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Winding:
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Winding temperature ranges from a minimum of 192°C to a maximum of 202 °C.
[0038]
Temperature Rise Simulation (With Designed Cooling System - Coolant EGW 60:40): 20
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Bearing Temperature:
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Front and rear bearing temperatures range between 59 °C – 63 °C.
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Winding Temperature:
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Winding temperature ranges from 57 °C to 64 °C.
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End Ring Temperature: 25
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End ring temperature ranges between 77 °C and 79 °C.
[0039]
The simulation results with a 400V DC input system provide a comprehensive understanding of the motor's performance and thermal characteristics. The key
14
observations from the simulations, as detailed in Sl No. 16, Sl No. 17, and Sl No. 18
of the drawing list, are summarized below:
[0040]
Simulation Results with 400V DC Input:
•
Torque Characteristics:
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Maximum torque of 501 Nm observed up to 800 RPM speed. 5
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Torque sharply reduced to 100 Nm within 2000 RPM and gradually decreases with an increase in speed.
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Maintains a torque of 40-50 Nm till the end of the simulation speed at 12500 RPM.
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Efficiency at Different Speeds: 10
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Maximum efficiency (approximately 95%) observed within the speed range of 2000 RPM.
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Efficiency gradually reduces to 82% up to the end of the simulation speed of 12500 RPM.
[0041]
Temperature Rise Simulation (Without Cooling System): 15
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Motor Housing:
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Average temperature of the motor housing is 192 °C.
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Rotor:
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Average temperature of the rotor is 207 °C.
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Stator: 20
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Average temperature of the stator is 194 °C.
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Winding:
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Average winding temperature is 201 °C.
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Minimum winding temperature recorded is 192 °C.
[0042]
Temperature Rise Simulation (With Designed Cooling System): 25
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Housing Temperature:
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Housing temperature ranges between 59 °C – 63 °C.
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Rotor Temperature:
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Rotor temperature is recorded at 78 °C.
15
•
Stator Temperature:
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Stator temperature is maintained at 61 °C.
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Winding Temperature:
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Average winding temperature is 55 °C.
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Minimum winding temperature recorded is 48 °C. 5
[0043]
Based on the simulation results, it is concluded that the designed motor successfully meets all the technical norms of electromagnetics in motor design. The outputs generated by the simulation, including torque, speed, efficiency, and temperature rise profile, along with the low weight and volume of the motor body, make it an ideal candidate for electric vehicle (EV) applications. The motor's 10 performance under different voltage conditions and the effectiveness of the cooling system contribute to its suitability for demanding EV propulsion scenarios.
[0044]
These simulation results demonstrate the motor's robust performance under different operating conditions, highlighting the effectiveness of the designed cooling system in maintaining lower temperatures across critical components such as 15 bearings, winding, and end rings. The observed torque, efficiency, and speed characteristics provide valuable information for assessing the motor's suitability for electric vehicle applications.
[0045]
The following detailed description and the subsequent comprehensive explanation pertains to the accompanying illustrations, which depict exemplary 20 embodiments of the current invention. Nevertheless, the extent of this invention is not restricted to these embodiments; rather, it is determined by the appended claims. Consequently, the present invention may encompass variations, including modified renditions of the illustrated embodiments, not explicitly depicted in the accompanying drawings. 25
[0046]
References in the specification to “one embodiment,” “an embodiment,” “an example embodiment,” or the like, indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Furthermore, 30
16
when a particular feature, structure, or characteristic is described in connection with
an embodiment, it is submitted that it is within the knowledge of one skilled in the relevant art(s) to implement such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
[0047]
While the embodiments of the disclosure are subject to various 5 modifications and alternative forms, specific embodiments thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to panel all modifications, equivalents, and alternatives falling within the scope of the disclosure. 10
[0048]
The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to panel a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a 15 system or device preceded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.

20 Biswajit Sarkar
25 Attorney for the Applicant
Registration No. IN/PA/152
30
, Claims: CLAIMS
We Claim:
1. Claim 1: A liquid-cooled induction motor for electric vehicles, comprising:
- a stator with a outer diameter of 248mm, a length of 140mm, and 54 slots;
- a rotor with 42 slots, incorporating copper rotor bars and end rings made of solid copper;
- a shaft with cooling holes, fitted into the rotor core;
- a pressured liquid cooling system encompassing the stator body, shaft, flanges, and bearings, effectively reducing the overall mass of the motor body;
- an end shield assembly with cooling paths, comprising a drive end side end shield and a non-drive end side end shield with internal and external details;
- a motor body configured for efficient cooling, with cooling paths shown in a motor body without end shields and rotor;
- a stator core without winding and a rotor core with copper bars and end rings inserted inside the stator core, the calculated dimensions of the motor without end covers fitted indicated in drawings.
2. The liquid-cooled induction motor as claimed in Claim 1, wherein the stator incorporates a double layer lap winding, and the rotor bars and end rings are made of solid copper, as specified in the material specifications document labeled Sl No. 12.
3. The liquid-cooled induction motor as claimed in Claim 1, designed to operate with either input voltages of 800VDC or 400VDC using inverter, maintaining a maximum torque of 501Nm, irrespective of the applied input voltage.
4. The liquid-cooled induction motor as claimed in Claim 1, designed to operate efficiently with a wide range of input voltages, addressing the diverse needs of electric vehicle applications.
5. A liquid-cooled induction motor for electric vehicles, as claimed in Claim 1, with a weight of approximately 58 kgs, a specific electrical loading of approximately 77000 Am, and an output of around 300 kW at a power factor of 0.86.
6. The liquid-cooled induction motor as claimed in Claim 1, featuring a cooling system using coolant EGW 60:40, effectively managing temperatures across critical components such as bearings, winding, and end rings.
7. The liquid-cooled induction motor as claimed in Claim 1, wherein the simulation results with 800V DC input system in Sl No. 13 and Sl No. 14, demonstrating torque development, system efficiency up to 96%, motor speed up to 14930 RPM, and maintaining high efficiency within the speed range of 3000 RPM to 8000 RPM.
8. The liquid-cooled induction motor as claimed in Claim 1, wherein the simulation results with 400V DC input system in Sl No. 16, Sl No. 17, and Sl No. 18, demonstrating torque characteristics, efficiency up to 95%, and effective thermal management, making it suitable for electric vehicle propulsion.
9. A method for manufacturing a liquid-cooled induction motor for electric vehicles, comprising the steps of designing the stator and rotor cores, selecting core materials, incorporating a pressured liquid cooling system, and optimizing dimensions for weight reduction and efficiency, as detailed in Sl No. 2, Sl No. 3, Sl No. 4 & 5, and Sl No. 9, Sl No. 10, Sl No. 11 of the drawing list.

Biswajit Sarkar
Attorney for the Applicant
Registration No. IN/PA/152