Multidisciplinary analysis of the transient performance of a 20 kW class HTS induction/synchronous motor cooled with a cryocooler and gaseous air-gap coolant

Abstract

This paper presents a multidisciplinary analysis procedure for the transient cooling and rotating characteristics of a 20 kW class high temperature superconducting (HTS) induction/synchronous motor, this analysis couples the nonlinear voltage equations, equation of motion, and a thermal equivalent circuit. First, the quantitative accuracy of the thermal equivalent circuit is validated through comparison with results obtained using the 3D finite element analysis. Then, multidisciplinary analysis is performed with the assumption that the outer surface of the stator is cooled by a cryocooler and the air-gap between the stator and rotor is cooled by a gaseous coolant.It is demonstrated that the transient performance of the motor can be fully determined using our developed procedure. For instance, we can determine the gas-flow speed in the air-gap required for cooling of the HTS rotor, by assuming appropriate expressions for the heat transfer in the air-gap.The analysis procedure and obtained results are effective for investigation of the variable speed performance of an HTS motor system and for optimal design of the motor cooling structure and method.

Optimization Methodology of PMSM Cooled by External Convection in Aircraft Propulsion

“…x for turbulent flow (15) These values can be used in a thermal finite element analysis, where the following equation must be solved:…”

“…(Step 4) The last step for the generation of initial population is the verification of thermal limits. Using the Equations (14) and (15), the heat transfer coefficients are calculated for an altitude of 100 m and for an appropriate speed of air stream. The solution of thermal problem (16) with the FEA gives the temperature distribution in the main part of the motor.…”

“…The three parts are further discretized with step ∆x along the axial direction in order to consider the variation of heat exchange coefficient along the external surface. For each disk obtained, the local heat exchange coefficient is calculated according to the Nusselt number [14,15]. This procedure permits the reduction of computational cost with respect to the 3D analysis and gives a good precision compromises with respect to the 3D analysis, though the axial heat distribution is neglected.…”

“…The researches [11] are carried out with the goal to increase the power density, the reliability and the efficiency. Many types of electrical machines are considered: 2 of 22 induction motor [12,13], permanent magnet synchronous motor [14] (the most utilized), and traditional synchronous machine above all with superconducting characteristics [15,16].…”

A novel solar‐powered master‐slave electric motor‐based energy‐saving and cooling approach for the motors of conveyor system

“…The increase in the motor volume further reduces the power density of the motor 9 . As an alternative to the air, the use of inert gases like helium or neon causes inhalation risk, since on loss of containment, this gas can cause suffocation by lowering the oxygen content of the air in confined areas and thereby, it can be responsible for health hazards 13 . These air or gas‐induced problems motivated the authors for the design and development of air and gas‐free cooling system for the motors and the proposed work is independent of air or any gaseous component for the heat dissipation of motors.…”