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Article
Publication date: 5 October 2022

Qiang Fu and Xiaojuan Lv

The purpose of this study is to analyze the linear induction motor (LIM) thermal field when the motor passes through the discontinuous area of the secondary plate in rail transit…

Abstract

Purpose

The purpose of this study is to analyze the linear induction motor (LIM) thermal field when the motor passes through the discontinuous area of the secondary plate in rail transit operation.

Design/methodology/approach

To study the thermal field when the LIM passes through the discontinuous area of the secondary plate, the two-dimensional (2D) electromagnetic field model of the motor is first established to calculate and analyze the electromagnetic field of the LIM, and then the motor thermal field is calculated according to the calculation results of the motor electromagnetic field. Finally, the heat source (the motor loss) and the heat dissipation coefficient are added to the thermal field calculation model to calculate the motor thermal field.

Findings

This study found that the discontinuity of the secondary board would lead to changes in the electromagnetic field of the linear induction motor to change, which would reduce the motor efficiency and increase the loss, resulting in a sudden increase in the temperature field of the motor.

Originality/value

The LIM temperature field calculation when the LIM passes through the discontinuous area of the secondary board could provide an early warning for the potential risks of the LIM in rail transit applications.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 February 2024

Gerasimos G. Rigatos, Pierluigi Siano, Mohammed S. Al-Numay, Bilal Sari and Masoud Abbaszadeh

The purpose of this article is to treat the nonlinear optimal control problem in EV traction systems which are based on 5-phase induction motors. Five-phase permanent magnet…

Abstract

Purpose

The purpose of this article is to treat the nonlinear optimal control problem in EV traction systems which are based on 5-phase induction motors. Five-phase permanent magnet synchronous motors and five-phase asynchronous induction motors (IMs) are among the types of multiphase motors one can consider for the traction system of electric vehicles (EVs). By distributing the required power in a large number of phases, the power load of each individual phase is reduced. The cumulative rates of power in multiphase machines can be raised without stressing the connected converters. Multiphase motors are also fault tolerant because such machines remain functional even if failures affect certain phases.

Design/methodology/approach

A novel nonlinear optimal control approach has been developed for five-phase IMs. The dynamic model of the five-phase IM undergoes approximate linearization using Taylor series expansion and the computation of the associated Jacobian matrices. The linearization takes place at each sampling instance. For the linearized model of the motor, an H-infinity feedback controller is designed. This controller achieves the solution of the optimal control problem under model uncertainty and disturbances.

Findings

To select the feedback gains of the nonlinear optimal (H-infinity) controller, an algebraic Riccati equation has to be solved repetitively at each time-step of the control method. The global stability properties of the control loop are demonstrated through Lyapunov analysis. Under moderate conditions, the global asymptotic stability properties of the control scheme are proven. The proposed nonlinear optimal control method achieves fast and accurate tracking of reference setpoints under moderate variations of the control inputs.

Research limitations/implications

Comparing to other nonlinear control methods that one could have considered for five-phase IMs, the presented nonlinear optimal (H-infinity) control approach avoids complicated state-space model transformations, is of proven global stability and its use does not require the model of the motor to be brought into a specific state-space form. The nonlinear optimal control method has clear implementation stages and moderate computational effort.

Practical implications

In the transportation sector, there is progressive transition to EVs. The use of five-phase IMs in EVs exhibits specific advantages, by achieving a more balanced distribution of power in the multiple phases of the motor and by providing fault tolerance. The study’s nonlinear optimal control method for five-phase IMs enables high performance for such motors and their efficient use in the traction system of EVs.

Social implications

Nonlinear optimal control for five-phase IMs supports the deployment of their use in EVs. Therefore, it contributes to the net-zero objective that aims at eliminating the emission of harmful exhaust gases coming from human activities. Most known manufacturers of vehicles have shifted to the production of all-electric cars. The study’s findings can optimize the traction system of EVs thus also contributing to the growth of the EV industry.

Originality/value

The proposed nonlinear optimal control method is novel comparing to past attempts for solving the optimal control problem for nonlinear dynamical systems. It uses a novel approach for selecting the linearization points and a new Riccati equation for computing the feedback gains of the controller. The nonlinear optimal control method is applicable to a wider class of dynamical systems than approaches based on the solution of state-dependent Riccati equations.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 43 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 5 July 2013

Krzysztof Krykowski, Janusz Hetmańczyk and Dawid Makieła

When phase windings of brushless DC motor are switched, additional voltage drops across inductances of main circuit appear. These drops lead to, among other effects, increase of…

Abstract

Purpose

When phase windings of brushless DC motor are switched, additional voltage drops across inductances of main circuit appear. These drops lead to, among other effects, increase of torque‐speed curve slope. The discussed research has been aimed at working out a simple and precise method of identifying torque‐speed characteristic of PM BLDC motor. The elaborated method takes into account the influence of windings switching and motor inductances on motor torque‐speed characteristic. In order to assess the results, extensive test simulations of models implemented in Matlab/Simulink software have been run. Results of analysis and test simulations have been compared with lab test results of two real PM BLDC motors.

Design/methodology/approach

Analytical calculations take into consideration phenomena occurring during windings switch‐overs and impact of inductance on emerging voltage and rotational speed drops. It has been pointed out that on account of main circuit inductance, the average value of source current is less than average value of equivalent current generating electromagnetic torque. For analysis sake it has been assumed when windings are being switched‐over the current is kept constant; the motor parameters have also been assumed to be constant.

Findings

A novel and accurate method of determining torque‐speed characteristics of PM BLDC motor has been worked out. This method has been investigated with the help of motor computer models implemented in Matlab/Simulink software and the obtained results have been subsequently compared with results of laboratory tests of two commercially available PM BLDC motors.

Research limitations/implications

The object of the research was brushless DC motor with permanent magnet excitation. The impact of windings switch‐overs on torque‐speed curves of the motor has been analysed. Analytical method which makes it possible to determine torque‐speed curve of this motor very easily has been elaborated. Computer model of PM BLDC motor for Matlab/Simulink software has also been worked out. Extensive simulations helping to verify the proposed method have been run. Results of analysis and simulation tests have been verified by means of laboratory tests of two commercially available PM BLDC motors.

Practical implications

PM BLDC motors are used more and more widely. The new method of determining PM BLDC motors torque‐speed curves will facilitate analysis and design of drive systems utilizing these motors and will also speed up calculations.

Originality/value

The presented method of determining torque‐speed curves of PM BLDC motor is novel and much more precise than methods commonly used nowadays. Recognized methods usually neglect impact of inductance on motor properties.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 14 August 2007

Jerzy Kołowrotkiewicz, Mariusz Barański, Wojciech Szelęg and Lech Długiewicz

The paper aims to elaborate the method and algorithm of analysis of induction motor working in cryogenic temperature.

Abstract

Purpose

The paper aims to elaborate the method and algorithm of analysis of induction motor working in cryogenic temperature.

Design/methodology/approach

This paper presents the design and investigation of performance characteristics of three‐phase high voltage squirrel‐cage submerged motor. The motor is intended to work at cryogenic temperature −161°C in liquefied natural gas (LNG). The time‐stepping finite element method of transients analysis in induction motor working in cryogenic temperature has been presented. The nonlinearity of the magnetic circuit, the movement of the rotor and skewed slots have been taken into account.

Findings

The study finds that presented method and elaborated software are used to determine the steady state and dynamic performance of the high voltage squirrel‐cage submerged motor. The results of simulations and measurements of constructed model motor have been presented.

Research limitations/implications

The problem has been considered as the 2D one. In order to take into account the skewed slots of the rotor the multi‐slice finite element method has been used.

Practical implications

Investigation presented in the paper has been performed in order to study the influence of the temperature on motor characteristics and to verify design calculations. No‐load current, starting torque and short‐circuit current during short‐circuit test, obtained on the basis of measurements and received from calculations, are in good concordance.

Originality/value

The paper proposes a method to determine the steady state and dynamic performance of the high voltage squirrel‐cage submerged motor working in cryogenic temperature.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 December 2005

S. Subramanian and R. Bhuvaneswari

This paper presents a novel multiobjective optimal design of three phase induction motor using simulated annealing (SA) technique for minimizing annual material cost and annual…

Abstract

Purpose

This paper presents a novel multiobjective optimal design of three phase induction motor using simulated annealing (SA) technique for minimizing annual material cost and annual loss cost as two objectives.

Design/methodology/approach

The design problem of a three‐phase induction motor is presented as a nonlinear multicriterion optimization problem on the basis of minimizing the annual cost of the motor. The annual cost referred is the sum of the annual interest and depreciation of motor active material costs, annual cost of active power loss of the motor and the annual energy cost required to supply such power loss. A computer package is built which generates initial values of motor parameters and gives the optimal values of these parameters with more than one objective function and nonviolated constraints. The problem is solved by giving weights which reflect the priority of objective functions. The SA technique is used as a tool to solve the problem.

Findings

To verify the validity, the proposed method is applied to a three‐phase induction motor design. From the results, it is found that the proposed method is fast and efficient and hence it is useful for multiobjective design of an induction motor.

Originality/value

This method is particularly useful in satisfying the needs of motor producer and consumer by prioritizing their needs and finally arriving at a best compromise solution.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 24 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 4 March 2022

Gurkan Ortamevzi and Yalcin Sahin

The purpose of this paper is to make a more precise prediction of the life of servo motors used in aircraft. The variation of the axial load created by the wave washer for…

Abstract

Purpose

The purpose of this paper is to make a more precise prediction of the life of servo motors used in aircraft. The variation of the axial load created by the wave washer for bearing, which is one of the factors affecting the bearing life of the electric motors and servo motors used in aircraft, was analyzed.

Design/methodology/approach

In electric motors and servo motors that body as stator, the height of the stator stack affects the compression amount of the wave washer spring. Working with electric motor and servo manufacturers, production-related variations in stator height were determined by making multiple measurements. The reaction forces resulting from these compression amounts were simulated by mathematical modeling with the finite element method, and also experimentally measured on real parts.

Findings

Results obtained with finite element method and real experiments were compared. By adding the force differences to the general operating conditions, the effect on the bearing life was theoretically determined. In a servo motor with this type of construction, the difference in stator height created different axial loads on the motor shaft. The difference of these loads affected the motor bearing life.

Research limitations/implications

The results implicated in terms of flight safety, maintenance operation and resource efficiency.

Practical implications

The results of this study are effective in determining the maintenance intervals more clearly. This study can be used for the design criteria of aircraft servo motors. These servos, which are especially used to move the flight control surfaces, contribute to flight safety as the life expectancy will be clearer.

Social implications

This study may be effective in preventing aviation accidents caused by servo motors. It can make maintenance management more efficient.

Originality/value

This study investigated the effect of aircraft servo motor design inputs on servo motor life, considering the production.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 2 January 2009

Marian Łukaniszyn and Adrian Młot

This paper deals with magnetic field calculations and model‐based prediction of electromagnetic torque pulsations in a brushless DC (BLDC) motor.

Abstract

Purpose

This paper deals with magnetic field calculations and model‐based prediction of electromagnetic torque pulsations in a brushless DC (BLDC) motor.

Design/methodology/approach

The impact of a Halbach‐like magnetization and a multipolar excitation of permanent magnets are analysed. The measurement results from the prototype motors are well‐compared with those obtained from the model calculations. It is shown that the cogging torque in the motor with the multipolar excitation of permanent magnets is reduced six times as compared with the conventional BLDC motor.

Findings

The proposed method provides high accuracy of the analysis of coupled electromagnetic phenomena. The comparison between measured and calculated values of electromagnetic torque, cogging torque and EMF shows a very good agreement.

Practical implications

Reduction of the machine cogging torque is essential for practical applications of DC motors, in particular in the robotics industry.

Originality/value

This paper shows that multipolar excitation contributes to essential reduction of the cogging torque in a BLDC motor. This is confirmed by high‐quality numerical models of the motor, positively verified in experiments with motor prototypes.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 28 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 June 2002

P. Vas, M. Rashed, A.K.M. Joukhadar and C.H. Ng

The present paper will discuss newly developed fully digital sensorless induction motor and permanent magnet motor synchronous motor drives, which employ natural field orientation…

Abstract

The present paper will discuss newly developed fully digital sensorless induction motor and permanent magnet motor synchronous motor drives, which employ natural field orientation (NFO). So far only vector‐type of NFO induction motor drives have been discussed in the literature, and very limited experimental results have been shown. In addition, the paper will also discuss new sensorless DTC‐type of NFO induction motor drives (NFO‐DTC drives). Using fully digital implementations of the new NFO‐type induction motor and permanent magnet drives, experimental results will be shown for various operating conditions, including slow and fast reversals at very low speed. Robustness to parameter deviations will also be demonstrated. The developed new types of NFO drives can also work at zero stator frequency and sustained zero frequency operation will also be demonstrated. The drives have been tested in basically two environments: where the load is a dc motor; and where a crane drive is implemented. In contrast to other sensorless crane drives, which develop stability problems, it was found that the new NFO drives can operate in a stable manner under all operating conditions including zero frequency. This allows for many new applications.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 21 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 June 2003

Marian Lukaniszyn, Mariusz Jagiela and Rafal Wrobel

A brushless, permanent magnet, three‐phase disc‐type salient‐pole DC motor with co‐axial flux in the stator is considered. Electromechanical properties of a basic eight‐pole motor

Abstract

A brushless, permanent magnet, three‐phase disc‐type salient‐pole DC motor with co‐axial flux in the stator is considered. Electromechanical properties of a basic eight‐pole motor are compared with those for a 16‐pole one of the same volume, in order to contrast the two potential candidates for variable‐speed, low‐cost drives. As a basis of the comparative analysis, 3D FEM magnetic field modelling and circuit analysis considering an electronic commutator are employed. Increasing the number of poles results in unfavourable raising in the switching frequency. The eight‐pole motor construction has been shown in simulations to have higher efficiency and lower power losses than its 16‐pole counterpart.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 22 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 7 November 2016

Hokyung Shim, Jihyun Kim and Jungpyo Hong

The purpose of this paper is to study the electric vehicle (EV) drive efficiency of a traction motor considering regenerative braking according to various motor cores.

Abstract

Purpose

The purpose of this paper is to study the electric vehicle (EV) drive efficiency of a traction motor considering regenerative braking according to various motor cores.

Design/methodology/approach

A software program was developed to predict the driving performance of an EV. It determines the driving mileage, the required power of the traction motor, and the operation points on a torque-speed map when drive cycles are given. The driving performance is calculated from the battery capacity, vehicle specification, and efficiency map of the traction motor computed using the finite element analysis.

Findings

As a result, the motor core is a significant design variable for raising the driving mileage of an EV. It is noted that the change of electrical steels used for the motor core is the lowest priced method of increasing the driving range by 2 km.

Originality/value

The comparative analysis of motor core by replacing 35PN250 to 25PNX1250F results in improvement effects traveling 4.62 and 5.16 km farther in the Simplified Federal Urban Driving Schedule (SFUDS) and Highway Fuel Economy Driving Schedule (HWFET), respectively. It was also verified that regenerative braking system is able to enhance drive efficiency by 29-31.3 km in the SFUDS and 6.5-7.3 km in the HWFET. From comparison of price rise for increasing driving mileage by 2 km, it is noted that the change of electrical steels used for the motor core is the lowest priced method.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 35 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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