Fig 9 - uploaded by Stjepan Stipetic
Content may be subject to copyright.
Influence of router length L c on the fan inlet flow/velocity distribution V. CONCLUSION This paper presents a two stage design of the centrifugal fan for an IPM traction motor. Analytical expressions are first used for basic sizing of the fan. Further optimization of the fan (and other cooling system segments) in order to produce the maximum flow rate was performed using the CFD analysis, resulting in dimensions presented in Table I according to which the fan prototype shown in Fig. 10 was built and installed into the IPM motor.
Context in source publication
Context 1
... designated as r 1 is greater than the shaft radius. The inlet radius r 1 also affects the dimensions of the router, namely the router angle ϕ c , the increase of which results in decrease of the air flow resistance in the router. Longer router allows better developing of the flow, producing more even distribution of the flow at the fan inlet ( Fig. 9) which results in better fan performance. However, due to limited space, the longer router length reduces the fan impeller width b 1 and b 2 which deteriorates the fan ...
Similar publications
In the course of work on the project, we have created a permanent magnet synchronous motor, which will be effectively used in the oil industry, or rather 2 models: 15and 55-kW motors. After the tests carried out, the problem with the achievement of the specified value of the efficiency of the engines was clarified, and it was necessary to solve thi...
Citations
... However, as the cooling and maintenance costs for liquid cooling systems are relatively high, air-ventilated structures with open or enclosed structures have been widely employed. Jercic et al, [8] describe a two-stage design for a centrifugal fan mounted on a motor shaft. The fundamental fan sizing is determined by analytical formulas, and it is then decided based on CFD analysis. ...
This paper presents the design optimization of a self-circulated ventilation system for an enclosed permanent magnet (PM) traction motor utilized in the propulsion systems for subway trains. In order to analyze accurately the machine's inherent cooling capacity when the train is running, the ambient airflow and the related heat transfer coefficient (HTC) are numerically investigated considering synchronously the bogie installation structure. The machine is preliminary cooled with air ducts set on the motor shell, and the fluidic-thermal field distributions with only the shell air duct cooling are numerically calculated. During simulations, the HTC obtained in the former steps is applied to the external surface of the machine to model the inherent cooling characteristic caused by the train movement. To reduce the temperature rise and thus guarantee the motor's working reliability, an internal self-circulated air cooling system is proposed according to the machine temperature distribution. The air enclosed in the end-caps is driven by the blades mounted on both sides of the rotor core and forms two air circuits to bring the excessive power losses generated in the heating components to cool regions. The fluid flow and temperature rise distributions of the cooling system's structural parameters are further improved by the Taguchi method in order to confirm the efficacy of the internal air cooling system.
... The authors and colleagues are now preparing validation experiments for the targeted IPM motor with the air cooling designed by the proposed theoretical estimation described in this paper; however, some more time is still needed. Instead, for validation of the proposed theoretical estimation, numerical results of an air-cooled IPM motor with the configuration shown in Table 2 by Jercic et al. [29] were used. They showed the steady-state temperature distribution of PMs and coils as shown in Table 3 when the minimum cooling-air flowrate is 0.096 m 3 /s at a rotation speed of 1700 rpm. ...
... The authors assumed the heat generation rate from the PM is 218.5 W and that from the coils is 3277.25 W. The motor of Jercic et al. has a simple air-cooling scheme different from the authors; therefore, the authors assumed several settings to allow the proposed theoretical estimation to simulate the motor of Jercic et al. First, internal air is always aspirated from the surroundings instead of recirculation; thus, inlet temperatures at both the heat exchanger and the rotor are fixed at 295 K. Second, the authors set the flowrate of the internal air at 0.00177 m 3 /s to keep the temperature of the PM at 147.6 C because Jercic et al. did not describe how they cooled the rotor in Ref. [29]. Third, the authors set a heat transfer coefficient at contact surfaces of internal air in the outer heat exchanger at 5 W/(m 2 ÁK) to simulate a natural convection cooling by the surrounding air (Table 4). ...
... Third, the authors set a heat transfer coefficient at contact surfaces of internal air in the outer heat exchanger at 5 W/(m 2 ÁK) to simulate a natural convection cooling by the surrounding air (Table 4). Table 5 Comparison between Ref. [29] and the proposed theoretical estimation ...
To enhance worldwide environmental conditions, the air transport industry must drastically reduce carbon dioxide emissions. Electrification of aircraft propulsion systems is one way to meet this demand. In particular, the focus is on obtaining single-aisle aircraft with partial turboelectric propulsion and approximately 150 passenger seats by the 2030s. To develop a single-aisle aircraft with partial turboelectric propulsion, an aircooled interior permanent magnet (IPM) motor with an output of 2 MW is desired. One of the most difficult problems in air cooling is that air-cooling performance decreases with increasing altitude because the air density decreases. To investigate the effect of altitude on air-cooling performance in the IPM motor, the authors formulated mathematical system equations to describe heat transfer inside the target air-cooled IPM motor, and mathematical analytical solutions were obtained. The most severe condition is the top-of-climb condition. For this condition, a designer should choose cooling air mass flow rates that keep the temperature of the permanent magnets below the maximum temperature limit of 100 °C and the temperature of the coils below the maximum temperature limit of 250 °C. Here, the sizes of the air-cooling channels strongly affect air cooling with the IPM motor. In this paper, the authors briefly review the mathematical formulations and their solutions, investigate the effect of channel size on air-cooling performance in an IPM motor, and explore the optimum configuration and settings for the air cooling channels.
... Here, for comparative purposes, the curved blades fan is simulated in clockwise and counter-clockwise directions and compared also with the radial blades fan case. Regarding the fan design, several key parameters would affect the performance; blade geometry, blade angle, inletoutlet radius ratio and number of blades [7], [30]- [31]. The curvature of the leading edge and blade tip is to form an airfoil shape that will lead the air velocity to increase from the edge to the tip. ...
... The maps of the scaled motor in Fig. 8 together with the d-q currents (Idmax, Iqmax), resistance (R) and losses (PCu) of the armature winding, and windage losses (Pw) of the scaled motor are given by [18] where the subscript 0 refers to the referent motor, the subscript co refers to the core region, and the subscript ew refers to the end winding region. The windage losses are caused by the cooling fan mounted on the motor shaft and for the referent motor they are determined by a 3D computational fluid dynamics (CFD) model [24] at the rated mechanical speed (ωm0) given in Table I. Since the speed of the tram is varying, the windage losses of the scaled motor are expressed as a function of speed using ...
... The model of the motor is implemented by combining (18) and (24) with nonlinear programming (MATLAB function fmincon) to obtain the optimal values of Id and Iq for the torque required by the traction effort curve of the driving cycle at a given speed to yield the MTPA control and to satisfy the DC bus voltage limit in the flux weakening regime. ...
... The step 3 has been thoroughly explained in the previously published conference paper [26]. In the step 4 the new cooling fan for the IPM motor has been designed to produce the required air flow to keep the stator winding within predefined thermal constraints and its design procedure is explained in a paper accepted for conference presentation [27]. ...
This paper presents a method for reducing computational time in constrained single objective optimization problems related to permanent magnet motors modeled using computationally intensive finite element method. The method is based on Differential Evolution algorithm. The principal approach is to interrupt the evaluation of inequality constraints after encountering the constraint which is violated and continue their evaluation only if better solutions are obtained in comparison with the candidate vector from the previous generation both in terms of inequality constraints and the cost function. This approach avoids unnecessary time consuming finite element calculations required for solving the inequality constraints and saves the overall optimization time without affecting the convergence rate. The main features of this approach and how it complements the existing method for handling inequality constraints in differential evolution algorithm is demonstrated on design optimization of an interior permanent magnet motor for the low-floor tram TMK 2200. The motor geometry is optimized for maximum torque density.
In recent years, the rapid development of the transportation industry has led more and more scholars to devote themselves to the research of its drive motor. Among all relevant aspects of research, thermal management is absolutely the one that has been neglected in the past but is now getting more and more attention. This paper presents a comprehensive and detailed summary of motor thermal management for transportation, including thermal analysis methods, key factors in thermal analysis, and various cooling methods. Firstly, the three mainstream thermal analysis methods are introduced, and the improvement of each method in recent years is summarized. The feasibility and advantages of multi-method united simulation are discussed, and some novel thermal analysis methods are also listed. Then, key factors in thermal analysis are analyzed in depth and the determination methods are given. In the fourth section, the research related to motor cooling methods in recent years is reviewed, including the improvement of traditional methods and novel methods. Finally, suggestions for the future development of thermal management are given. The key is not only to reveal novel analysis methods, tools, methodologies, cooling structures, strategies, pros and cons, and foresight for the advanced drive motor but also to provide guidelines for predicting the temperature distribution and selecting the appropriate cooling methods in the motor design process.
This paper presents a review in three parts on the current traction motor topologies available in the railway market. In the first part, essential aspects of the electromagnetic design of railway traction motors, e.g. motor sizing and rotor configurations, are discussed. Different topologies are compared considering the wide range of applications. The pros and cons of each topology in specific applications are highlighted based on the corresponding performance requirements. In the second part, different cooling configurations of traction motors common in railway are reviewed, focusing on the solutions based on air cooling. The third part presents a review of the available insulation systems for traction motors. Two primary insulation systems used in traction applications with thermal classes of H and N are discussed. The focus in this paper is placed on the main applications in railway including light rail vehicles, metros, electric multiple units, high speed trains, and locomotives. Additionally, trends in traction motors development in the coming years are reported separately for electromagnetic, cooling, and insulation designs.
This paper presents a simple model for the calculation of core losses in permanent magnet machines based on the total flux linkage of the stator winding. In reality, the total core losses will vary as a function of permanent magnet field and the combination of d-q current components even in the case when different d-q currents produce the same amount of stator winding flux linkage at a given speed. The classical model with constant equivalent core loss resistance predicts constant core losses for constant flux linkage which leads to incorrect results. The model presented in this paper expands the classical core loss resistance based model with a novel additional term which corrects the classical model and calculates an additional core loss component as a function of d axis current, total flux linkage of the stator winding, and two constant parameters. The accuracy of the model is confirmed by finite element simulations and core loss measurements for the cases of an interior permanent magnet traction motor and an industrial surface permanent magnet motor (only simulations).
