This paper gives a comprehensive review of advanced cooling schemes and their applications to the permanent magnet synchronous motors (PMSMs), as well as investigating the electrical motor’s topologies its thermal design issues, materials and performances. Particularly, the electromagnetic and electric performances, machine sizing, together with the structural design, are given. In addition, the work addresses the motor’s material design and properties along with its insulation performance, which is the main goal of optimization. Mainly, thermal mapping with analysis is provided according to the different cooling methods, including air-cooling, water-cooling, oil-cooling, heat-pipe-cooling, potting silicon gelatin cooling, and as well as cooling strategies for tubes and microchannels. The most common special features and demands of the PMSMs are described in the appearance of the motor’s failures caused by uncontrolled temperature rise. In addition, heat sources and energy losses, including copper loss, core loss versus motor speed, and output power, are analyzed. The review of the proposed cooling methods that will achieve the required heat transfer of the PMSM is presented with numerical simulations and measurements data. A review of numerical methods and results, including the finite element methods (FEM), such as the Ansys CFD software, to obtain a high-accuracy thermal mapping model of the PMSM system is given. The revived methods and design requirements due to PMSM temperature profile and cooling flow at different rotor speeds and torque loads are investigated. Finally, the motor design recommendations, including the newly developed cooling solutions, which enable it to effectively redistribute the temperature and heat transfer, increasing the efficiency of the PMSM machine, are laid out.

The correct strategy of heat management in electric machines is extremely important due to their operating costs and length of operation. In this paper, the thermal management element strategies of the induction motors are developed to assure better endurance and boost efficiency. Additionally, an extensive review of the literature was carried out in terms of cooling methods for electrical machines. As the main result, the thermal analysis of an air-cooled and large-capacity induction motor is given, considering well-known heat distribution problems. Moreover, this study also presents an integrated approach with two or more cooling strategies to be the need of the hour. A model of a 100-kW air-cooled induction motor and an improved thermal management model of the same motor were both numerically investigated, using a combination of air cooling and integrated water cooling systems to achieve a significant improvement in motor efficiency. The integrated system comprising air- and water-cooled systems are investigated using SolidWorks 2017 and ANSYS Fluent version 2021. Three different flow rates of water 5 LPM, 10 LPM and 15 LPM are analyzed and compared with a conventional air-cooled induction motor, which was validated with the available published resources. Performed analyses indicate that for different flow rates of 5 LPM, 10 LPM and 15 LPM respectively, we have obtained a reduction of temperature accordingly of 2.94%, 4.79% and 7.69%. Hence, the results indicated that an integrated induction motor is efficient in bringing down the temperature compared to air cooled induction motor.

Induction motors have gained a renewed interest due to this new shift from conventional power sources to electric power. These motors are known for their high commencing torque, adequate speed control and reasonable overload capacity. However, induction motors have an innate thermal issue wherein their lifespan and performance are strongly temperature dependent. Hence, it is highly essential to focus on the thermal management aspect of these motors to ensure reliability and enhance performance. Thus, the major purpose of the paper is to comprehensively review various approaches and methods for thermal analysis, including finite element analysis, lumped parameter thermal network and computational fluid dynamics tools. Moreover, it also presents various cooling strategies commonly adopted in induction motors. Furthermore, this study also suggests an integrated approach with two or more cooling strategies to be the need of the hour. These will combine the benefits of the individual system while helping to counter their drawbacks. This study will help to serve members of the scientific community, manufacturers or motors users who are interested in the thermal management of induction motors.