Disk motors are characterized by the axial direction of main magnetic flux and the variable length of the magnetic flux path along varying stator/rotor radii. This is why it is generally accepted that reliable electromagnetic calculations for such machines should be carried out using the FEM for 3D models. The 3D approach makes it possible to take into account an entire spectrum of different effects. Such computational analysis is very time-consuming, this is in particular true for machines with one magnetic axis only. An alternate computational method based on a 2D FEM model of a cylindrical motor is proposed in the paper. The obtained calculation results have been verified by means of lab test results for a physical model. The proposed method leads to a significant decrease of computational time, i.e. the decrease of iterative search for the most advantageous design.

Accurate information on Induction Motor (IM) speed is essential for robust operation of vector controlled IM drives. Simultaneous estimation of speed provides redundancy in motor drives and enables their operation in case of a speed sensor failure. Furthermore, speed estimation can replace its direct measurement for low-cost IM drives or drives operated in difficult environmental conditions. During torque transients when slip frequency is not controlled within the set range of values, the rotor electromagnetic time constant varies due to the rotor deep-bar effect. The model-based schemes for IM speed estimation are inherently more or less sensitive to variability of IM electromagnetic parameters. This paper presents the study on robustness improvement of the Model Reference Adaptive System (MRAS) based speed estimator to variability of IM electromagnetic parameters resulting from the rotor deep-bar effect. The proposed modification of the MRAS-based speed estimator builds on the use of the rotor flux voltage-current model as the adjustable model. The verification of the analyzed configurations of the MRAS-based speed estimator was performed in the slip frequency range corresponding to the IM load adjustment range up to 1.30 of the stator rated current. This was done for a rigorous and reliable assessment of estimators’ robustness to rotor electromagnetic parameter variability resulting from the rotor deep-bar effect. The theoretical reasoning is supported by the results of experimental tests which confirm the improved operation accuracy and reliability of the proposed speed estimator configuration under the considered working conditions in comparison to the classical MRAS-based speed estimator.

This paper presents a review of the electromagnetic field and a performance analysis of a radial flux interior permanent magnet (IPM) machine designed to achieve 80 kW and 125 Nmfor an electric and hybrid traction vehicle. The motor consists of a 12-slot stator with a three-phase concentrated winding as well as an 8-pole rotor with V-shaped magnets. Selected motor parameters obtained from an IPM prototype were compared with the design requirements. Based on the electromagnetic field analysis, the authors have indicated the parts of the motor that should be redesigned, including the structure of the rotor core, aimed at enhancing the motor’s performance and adjusting segmentation for magnet eddy current loss reduction. In addition, iron and PM eddy current losses were investigated. Moreover, transient analysis of current peak value showed that the current may increase significantly compared to steady-state values.Amap of transient peak current load vs. torque load plotted against rotor speed was provided. Based on the numeric and analytical results of physical machine parameters, the authors indicate that collapse load during the motor’s operation may significantly increase the risk of permanent magnet (PM) demagnetization. It was also found that collapse load increases the transient torque, which may reduce the lifetime of windings.

The aim of this study is to design a control strategy for the angular rate (speed) of a DC motor by varying the terminal voltage. This paper describes various designs for the control of direct current (DC) motors. We derive a transfer function for the system and connect it to a controller as feedback, taking the applied voltage as the system input and the angular velocity as the output. Different strategies combining proportional, integral, and derivative controllers along with phase lag compensators and lead integral compensators are investigated alongside the linear quadratic regulator. For each controller transfer function, the step response, root locus, and Bode plot are analysed to ascertain the behaviour of the system, and the results are compared to identify the optimal strategy. It is found that the linear quadratic controller provides the best overall performance in terms of steady-state error, response time, and system stability. The purpose of the study that took place was to design the most appropriate controller for the steadiness of DC motors. Throughout this study, analytical means like tuning methods, loop control, and stability criteria were adopted. The reason for this was to suffice the preconditions and obligations. Furthermore, for the sake of verifying the legitimacy of the controller results, modelling by MATLAB and Simulink was practiced on every controller.

An electric power steering system (EPS) is a new type of steering system developed after a mechanical hydraulic power system (MHPS) and electric-hydraulic power steering system (EHPS). In order to coordinate and solve the portability and sensitivity of the steering system optimally, taking an induction power steering system as the research object, the control algorithm of induction motor control under the EPS is studied in this paper. In order to eliminate the feed-forward performance degradation caused by the change of feed-forward parameters, an on-line identification algorithm of feed-forward parameters is proposed. It can improve the control performance of online identification among three feed-forward parameters in the T-axle motor, it improves on the robustness of feed-forward control performance, at the same time it also gives simulation and test results. This method can improve the control performance of the three feed-forward parameter online identification of the T-axis motor and improve the robustness of feed-forward control performance. At the same time, simulation and test results are given. The simulation results show that the algorithm can significantly improve the response speed and control accuracy of EPS system control.

A brushless direct-current (BLDC) and permanent-magnet synchronous motors (PMSMs) with permanent magnets are characterised by the highest operating parameters among all electric motors. High dynamics and the possibility of controlling their work improves the operating parameters of the drive system and reduces the operating costs of such a device. The high cost of these machines associated with the complexity of their construction is a serious barrier to increasing their range in small propulsion systems, where lower energy consumption does not give such spectacular financial profits. To reduce costs, manufacturers often limit the variety of manufactured engines so that by increasing the volume, the unit cost of the device can be minimised. This is often hindered by the implementation of projects deviating from standards where it is necessary to use drive systems of different power. The solution to this problem could be the use of two independent drive systems working in strict correlation to ensure sufficient operating parameters of the device. The article presents a method of controlling a drive system in which two propulsion systems with PMSM engines were used. These devices are communicated with each other by a serial bus, by means of which data necessary for the correct operation of motors connected by a drive belt are transmitted. Since these machines affect both the working machine and each other, it is necessary to optimise such a system so as to avoid excessive oscillation of the drive torque in the system.

This paper deals with the finite element analysis of the demagnetization process of the line start permanent magnet synchronous motor. Special attention has been paid to demagnetization risk assessment after resynchronization during a short-term supply power outage. The current and torque waveforms have been determined assuming the difference depending initial rotor position angle. It has been demonstrated that the highest demagnetization risk occurs when resynchronization (motor reclosing) is performed whe induced electromotive forces are in anti-phase to the supply voltage waveforms. The effect of cage winding resistance on the risk of demagnetization is examined and discussed.

The unique oasis of Zousfana, on the western edge of the Grand Erg Occidental, Taghit is the pearl of the oases of Saoura, a palm grove of 180 ha over an 18 km length crossed by Oued Zouzfana. It regroups the different types of landscapes of an arid zone (erg, hamada, barga – a small hill, oued ...). Taghit is known for its hydraulic civilization, the oasis in its hostile environment has survived thanks to the exploitation of rare groundwater irrigation according to the traditional customs applied to the whole of society. The peasants spur out the water resources through foggaras and traditional wells. But the intervention of modern irrigation techniques in an anarchic way has disrupted the fragile mode of irrigation and the abandonment of the palm grove. The over-exploitation of groundwater by the use of boreholes and motor pumps leads to the drying up of water sources, mists and traditional wells. Today, only 45 000 palm trees are productive and less than 1500 fruit trees. There are 500 fellahs in the entire agricultural area of Taghit, the majority of them is fleeing work in the oasis because of the lack of income from it. When comparing the results of analyses from different campaigns (2015 and 2008), a spectacular increase in the salt concentrations in the groundwater of the different palm groves is noticed. According to our investigations, the main causes of this jump are: the overexploitation of the water tables by motor pumps, the abandonment of land inside the palm grove, the lack of maintenance of the gardens, the exploitation of domestic wastewater in the irrigation. According to this preliminary study, it is important for the State to make farmers aware of the role of their traditional irrigation systems in the continuity of the oasis and life in it.

The multi-phase permanent-magnet machines with a fractional-slot concentrated-winding (FSCW) are a suitable choice for certain purposes like aircraft, marine, and electric vehicles, because of the fault tolerance and high power density capability. The paper aims to design, optimize and prototype a five-phase fractional-slot concentrated-winding surface-mounted permanent-magnet motor. To optimize the designed multi-phase motor a multi-objective optimization technique based on the genetic algorithm method is applied. The machine design objectives are to maximize torque density of the motor and maximize efficiency then to determine the best choice of the designed machine parameters. Then, the two-dimensional Finite Element Method (2D-FEM) is employed to verify the performance of the optimized machine. Finally, the optimized machine is prototyped. The paper found that the results of the prototyped machine validate the results of theatrical analyses of the machine and accurate consideration of the parameters improved the acting of the machine.

This paper investigates the application of a novel Model Predictive Control structure for the drive system with an induction motor. The proposed controller has a cascade-free structure that consists of a vector of electromagnetics (torque, flux) and mechanical (speed) states of the system. The long-horizon version of the MPC is investigated in the paper. In order to reduce the computational complexity of the algorithm, an explicit version is applied. The influence of different factors (length of the control and predictive horizon, values of weights) on the performance of the drive system is investigated. The effectiveness of the proposed approach is validated by some experimental tests.