Power systems
Reza Ghanizadeh; Hamed Azadrou
Abstract
Bearing-less induction motors (BLIMs) are suitable candidates for high-speed applications but suffer from low torque density and complex control issues due to the interaction of torque and levitation forces. To address these challenges, this paper presents a new control strategy that combines vector ...
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Bearing-less induction motors (BLIMs) are suitable candidates for high-speed applications but suffer from low torque density and complex control issues due to the interaction of torque and levitation forces. To address these challenges, this paper presents a new control strategy that combines vector control and direct torque control (DTC) for torque management, alongside a novel force control method based on finite element analysis (FEA). The proposed approach minimizes interference between torque and force magnetic fields by employing a parallel winding structure and distinct control units for torque and force. Simulation results demonstrate that the proposed method significantly reduces torque ripple and improves steady-state performance compared to conventional vector control and DTC. Furthermore, the force control unit outperforms a dual field-oriented control (FOC) method in regulating rotor position, offering better suspension force control and faster stabilization. This work contributes to the development of more efficient control strategies for BLIMs, enhancing their performance in industrial applications.
Control
Hamed Azadrou
Abstract
This paper explores the application of high-speed bearingless induction motors within compressor systems. These motors utilize two distinct electromagnetic fields to generate both torque and suspension forces, making them suitable for applications requiring high speed with an efficient operation. However, ...
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This paper explores the application of high-speed bearingless induction motors within compressor systems. These motors utilize two distinct electromagnetic fields to generate both torque and suspension forces, making them suitable for applications requiring high speed with an efficient operation. However, a significant challenge arises from the interference between these fields, which can negatively impact motor performance. To address this issue, we propose a new rotor structure that mitigates the interference problem. The proposed structure is based on the utilization of multiple dual-pole rotors positioned together, each of which is electrically separate from the others. Subsequently, we focus on optimizing the motor's dimensions to enhance both torque generation and suspension force capabilities. To achieve this optimization, a modern genetic algorithm is employed, allowing for comprehensive exploration of the design space. The results of the proposed optimized motor are compared with those of a motor optimized using a conventional algorithm. The findings affirm the effectiveness of our approach in improving motor performance.
Industrial Electronics
Allahverdi Azadrou; Siamak Masoudi; Shahla Gharaati
Abstract
This work presents finite element analysis, design, and construction of an improved linear switched reluctance motor for elevator application. In the proposed motor, both stator and translator have separate poles; thus, the motor is lighter and more appropriate for vertical motion applications. In addition, ...
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This work presents finite element analysis, design, and construction of an improved linear switched reluctance motor for elevator application. In the proposed motor, both stator and translator have separate poles; thus, the motor is lighter and more appropriate for vertical motion applications. In addition, the proposed structure has low core losses due to the separate and short magnetic paths. The only set of windings is placed on stator poles while the translator has no winding or permanent magnet. In order to broaden the positive force region, non-uniform air-gap is designed and optimized via non-dominated sorting genetic algorithm. Finite element analysis and experimental tests of the motor are performed and characteristics of the proposed structure are compared with a previous structure in the elevator application. Finite element analysis have been done in ANSYS software.The results confirm that the proposed linear motor has higher average force with an acceptable ripple in force.
Control
Allahverdi Azadrou; Siamak Masoudi; Reza Ghanizadeh; Payam Alemi
Abstract
This work deals with minimizing fluctuations of propulsion force and improving the motion quality in a linear switched reluctance motor. In order to minimize the jerks in the moving part of the motor, a new profile has been used to generate an appropriate reference speed profile. The results indicate ...
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This work deals with minimizing fluctuations of propulsion force and improving the motion quality in a linear switched reluctance motor. In order to minimize the jerks in the moving part of the motor, a new profile has been used to generate an appropriate reference speed profile. The results indicate that at speed 0.5 m/s, the motor reaches its command speed at the proposed time while, using conventional speed profile it takes almost 1.4 times the desired time. In order to control the speed and incease the motion quality, a simple fuzzy logic system has been used which is able to overcome the uncertainties problem in nonlinear systems. The fuzzy control system can regulate the motor performance so that it tracks the reference speed with minimum error and fluctuation. To illustrate the performance of the fuzzy method, a conventional PI method along with a model reference adaptive control (MRAC) strategy have been applied to the motor and the obtained results for three control methods have been compared. Speed overshoot using conventional PI method is about 20 percent of the final speed while this is about 6 percent for fuzzy and MRAC methods. The system is designed and its efficiency is shown through simulation and experimental tests in different performance situations . The obtained results confirm that the fuzzy strategy outperforms other methods.
