Line-start Synchronous Reluctance Motor Research Articles

Comparative analysis of energy performance of squirrel cage induction motor, line-start synchronous reluctance and permanent magnet motors employing the same stator design

Comparative analysis of energy performance of squirrel cage induction motor, line-start synchronous reluctance and permanent magnet motors employing the same stator design

Alternate Rotor Design for Line-Start Synchronous Reluctance Motor With Minimum Use of Copper

Alternate Rotor Design for Line-Start Synchronous Reluctance Motor With Minimum Use of Copper

Design and analysis of a new improved rotor structure in line-start synchronous reluctance motors

Design and analysis of a new improved rotor structure in line-start synchronous reluctance motors

Design and Analysis of Line-Start Synchronous Reluctance Motor Considering the Maximum Inertia and Power Factor

Design and Analysis of Line-Start Synchronous Reluctance Motor Considering the Maximum Inertia and Power Factor

Sensitivity-Based Design and Optimization of Line Start Synchronous Reluctance Motor

Energy resources are decreasing in the world and the use of electrical machines is increasing. Motor design and development studies are carried out to reduce the losses and increase the efficiency of motors, which are widely used especially in industry. In this study, Line Start Synchronous Reluctance Motor (LS-SynRM) was designed by taking an induction motor, one of the most widely used motors in the industrial field, as a reference. With its rotor cage structure feature, it can be line-start without the need of a driver. The rotor has a lot of design variables due to slots and barriers. Sensitivity analysis was used to determine the effect of design variables on performance criteria such as power factor, efficiency and torque ripple. Subsequently, Multi-Objective Genetic Algorithm (MOGA) optimization was used to find the values of the design variables that bring the motor performance closer to the optimum result. The results of the reference induction motor, initial LS-SynRM, and the optimized LS-SynRM are compared. It has been taken care to preserve the synchronization feature of the LS-SynRM and the related results are given in the analyses. It is shown that the optimized motor is in IE4 efficiency class and operates with low torque ripple.

Design and Performance Analysis of Three Phase Line Start Synchronous Reluctance Motor Using Finite Element Analysis

Three-phase Induction Motors (TPIM) are popular in industrial applications due to their numerous advantages. However, TPIM has comparatively lower efficiency than modern motor technologies like permanent magnet synchronous motor(PMSM), synchronous reluctance motor(SynRM), or switched reluctance motor(SRM). The expensive rare earth material and the inability of line starting operation discourage the replacement of TPIM with these modern energy-efficient motors. This research proposes a novel conversion of TPIM into Line Start SynRM (LS-SynRM) to cause a cost-effective and compatible performance solution. The proposed design modifications are carried out on the existing 0.5HP, TPIM rotor and analyzed using finite element (FE) software. The optimum barrier parameters such as barrier end width, barrier position, barrier width, and rib width have been determined through parametric analysis. The considerable effect of barrier dimensions on motor performance is evident from the analysis.

Improved Torque and Efficiency of Induction Motors by Changing Rotor Structure of Permanent Magnet Assistance Synchronous Reluctance Motors

Many authors have recently studied line start permanent magnet assistance synchronous reluctance. This paper presents a method to improve the electromagnetic torque and efficiency of induction motors of 7.5kW-4P (which consists of 36 stator slots and 40 rotor bars) by changing the design of the permanent magnet assistance synchronous reluctance rotors. This means that permanent magnets will be inserted to the squirrel cage induction motors (induction motors). The electromagnetic torque and efficiency of an induction motor is analyzed and compared with that of the line-start synchronous reluctance motor via a finite element analysis. In addition, the influence of position and length permanent magnets on the electromagnetic torque and efficiency of the line-start synchronous reluctance motor is also considered and simulated. The model of this motor Linh is finally designed with four U layered- magnet rotor to verify the developed method. The development of the method is also validated on the practical induction motor.

Design and Performance Analysis of Single Phase Line Start Synchronous Reluctance Motor Derived from Single Phase Induction Motor

ABSTRACT The single-phase induction motors (SPIMs) are predominantly used in the wider range of application developments. However, these motors have comparatively lower efficiency. Motors such as permanent magnet synchronous motor (PMSM), synchronous reluctance motor (SynRM), or switched reluctance motor are energy efficient. Although these motors posses high efficiency, the application cost becomes a significant concern. To cause the compatible performance of economical and conventional SPIM in terms of efficiency, lower temperature rise, weight reduction, and increased speed, this work addresses the conversion of SPIM into line-start SynRM (LS-SynRM). The required necessary modifications are analyzed using FEM. The design methodology is suggested for a typical 0.5HP SPIM that is tested in terms of rotor constructive parameters. The parametric sensitivity analysis is carried out using Ansys Maxwell FEM software. The rotor parameters such as cutout dimensions, type of barrier, their positions and widths, bridge thickness, pole arc to pole pitch ratios, and the end ring configurations are considered for the analysis. It has been determined that the efficiency is largely affected by the barrier positions and its width, and an improvement of two percent has been noted. However, the efficiency of LS-SynRM is also a function of bridge thickness, with higher values inferior is the efficiency.

Study on Analysis and Design of Line-Start Synchronous Reluctance Motor Considering Rotor Slot Opening and Bridges

According to International Electrotechnical Commission (IEC) 60034-1, in industrial applications not only efficiency but also power factors are important performance indexes. When comparing line motor to induction motor (IM), a line-start synchronous reluctance motor (LS-SynRM) has a high efficiency but a low power factor than that of IM. In this article, the analysis and design of LS-SynRM are carried out considering the rotor slot opening and bridges for improving the efficiency and power factor. The reference machine is selected with a 2.2 kW IM, and the performance of the reference model is analyzed based on finite element analysis (FEA). To analyze the effect of rotor slot opening and bridges, an optimal model of LS-SynRM is designed through a two-step design process. First, the design of rotor slot for synchronization is carried out, and second, the design of barriers using the response surface method (RSM) is carried out under the same conditions of the stator size of IM. Based on the basic model, the performances of LS-SynRM are analyzed according to the slot opening and bridges. Furthermore, the parametric analysis is carried out and the final model is designed considering the efficiency and power factor based on the design parameters. Finally, the final model is manufactured, and the experiment is carried out to verify the FEA result.

라인 기동식 릴럭턴스 전동기의 동기화 특성에 관한 연구

Line-start synchronous reluctance motor(LS-SynRM) has the high efficiency than the induction motor that is almost used in the industrial application. However, LS-SynRM must be operated in the synchronous speed for the high efficiency. When the load has high inertia, LS-SynRM fail to reach the synchronous speed. In this paper, the synchronization characteristics of LS-SynRM are analyzed based on the mathematical model and finite element analysis (FEA). The synchronization characteristics and the synchronous process of LS-SynRM are analyzed based on the mathematical model in s-δ plane. Furthermore, the condition of the synchronization is obtained by the kinetic energy and the motor energy. The three models are selected according to the rotor bar to analyze the synchronization characteristics using FEA. Using the time-harmonic analysis, the equivalent circuit parameters of the three models are calculated, and the starting characteristics and performance of LS-SynRM are compared.

Influence of Zero-Sequence Circulating Current on the Performance of Star-Delta Winding Line-Start Ferrite Assisted Synchronous Reluctance Motor.

To meet the new international efficiency (IE) standards, line-start (LS) synchronous reluctance motors (SyRMs) are now being considered. Conventional star and delta windings are usually employed in LS SyRMs. However, combined star-delta winding has higher winding factor and lower magneto-motive force (mmf) harmonics compared to conventional star and delta windings. Hence, in this paper, LS SyRM and LS ferrite assisted SyRM with star and star-delta winding are analyzed and their performance indices are compared. A winding function analysis is used for the design of star and star-delta windings. Further, the effect of zero sequence current on the performance of the motors under comparison is presented in detail. Star and star-delta winding prototype LS SyRMs with and without ferrite magnets in the rotor are fabricated. Experimental studies are carried-out on these prototypes and the results are presented which are in close agreement with the simulation results.

Line-Start Synchronous Reluctance Motor With V-Shaped Rotor Laminations

A line-start synchronous reluctance motor (LS-SynRM) that meets the IE4 efficiency and has satisfactory starting and synchronizing capabilities while operating with acceptable power factor will find application in constant speed drives. This paper introduces a line-start synchronous reluctance motor with V-shape rotor laminations (LS-SynRM-VSRL). The motor, which has been designed from an IE2-132S4 conventional foot mounted three-phase induction motor NEMA frame, was modeled using the three-dimensional (3D) Finite Element Method (FEM), then prototyped and tested for transient, dynamic, and steady-state performance under different load conditions. The Finite Element Analysis (FEA) and measured results of the LS-SynRM-VSRL are compared with those of a conventional line-start synchronous reluctance motor (CLS-SynRM). The results evidenced that both LS-SynRMs achieved successful synchronization on no-load, with the proposed LS-SynRM-VSRL reaching the steady state condition much quicker than the CLS-SynRM. Under steady-state operations, both LS-SynRMs achieved IE4 efficiency, with the proposed LS-SynRM-VSRL reaching an efficiency of 93.6% on full-load, in contrast to the 84.9% that the IE2-132S4 induction motor has achieved under the same loading condition.

Improved Performance Analysis of Single-phase Line Start Synchronous Reluctance Motor Derived from Induction Motor

Improved Performance Analysis of Single-phase Line Start Synchronous Reluctance Motor Derived from Induction Motor

Line-Start Synchronous Reluctance Motor: A Reduced Manufacturing Cost Avenue to Achieve IE4 Efficiency Class

Line-Start Synchronous Reluctance Motor: A Reduced Manufacturing Cost Avenue to Achieve IE4 Efficiency Class

FE-Aided Synchronization Analysis of Line-Start Synchronous Reluctance Motors

Since line-start synchronous permanent magnet motors (LSPMs) entered the market, they have attracted research interest toward counterpart induction motors of low power-ratings. This paper reports an investigation of line-start synchronous reluctance motors (LS-SynRMs). LS-SynRMs has not been investigated as much as LSPMs have. A motor needs to maximize rotor saliency to achieve high efficiency and a high power-factor. This results in complicated rotor geometry because the rotor cage and multiple flux barriers share the same rotor space. This paper provides an approximate method based on steady state torque analysis by which to estimate the critical inertia of a LS-SynRM. A finite element analysis (FEA)-aided analytical approach to the approximation of steady state torque is proposed to replace the more typical approach based on equivalent circuit parameters. The critical inertia resulting from the proposed method is compared to the results obtained using the FEA.

Line start synchronous reluctance motor with improved power factor for agriculture electric pump applications

Line start synchronous reluctance motor (LSRM) is more efficient than the existing induction motor (IM). However, the power factor is a major concern in LSRM. The power factor of the LSRM depends on the saliency ratio. To increase the saliency ratio, either d-axis inductance (Ld) has to be improved, or q-axis inductance (Lq) reduced. Here, q-axis inductance is decreased by making the minimal or negligible flux variation in the q-axis. Initially, the rotor geometry has been optimized employing an optimization algorithm. Then, finite element analysis is adopted to predict the capability of the designed rotors. Stress analysis has been carried out for both axial and radial rotor structures to verify the mechanical robustness. The fabrication steps such as folding, stacking and screwing, wire cut, die-casting and milling process of both the rotor structures are explained in detail. Further, both the machines are tested with the centrifugal pump. From the test results, it is observed that the proposed rotor structure provides a higher power factor.

라인 기동식 동기형 릴럭턴스 전동기의 설계 파라미터에 따른 동기속도 운전특성에 관한 연구

In this paper, the operating points of a line-start synchronous reluctance motor (LS-SynRM) are analyzed based on the mathematical model, and the performances such as efficiency and power factor are analyzed using a finite element analysis (FEA). Based on the mathematic model of LS-SynRM, the operating points is analyzed according to the dq-axis inductance. The design parameters that determine the dq-axis inductance and phase resistance are selected as a turn per slot, a stack length, and that determine a barrier design. Using a finite element analysis (FEA), the operating points are analyzed according to the design parameters. Furthermore, the performances of LS-SynRM according to the operating points are analyzed to consider the efficiency and power factor. The performance maps according to three design parameters are analyzed to optimize the efficiency and power factor. To verify FEA result, final LS-SynRM is manufactured and the experiment is performed.

Analysis of Selected Operating States of the Line Start Synchronous Reluctance Motor Using the Finite Element Method

The article presents the results of work on an effective numerical study of selected transient states of a low-power electrical machine. The object of detailed research was a synchronized squirrel-cage induction motor. Its ability to work at a synchronous speed was enabled by obtaining reluctance torque, caused by an imposed asymmetry between the direct and quadrature reluctances of the rotor. The difference between the reluctances was achieved by changing the rotor geometry by milling additional deep grooves. The modifications of the rotor did not damage the continuity of the rotor cage. Imposed lots were arranged symmetrically around the rotor circumference. In order to study the performance of the modified motor, a parameterized, numerical model of the machine was developed to evaluate the impact of the geometry of the slots. The developed three dimensional (3D) model of the electromagnetic phenomena in the studied magnetic circuit employs the finite element method (FEM). The model takes into account the saturation of the machine’s magnetic circuit and the skew of the rotor cage bars as well as the mechanical equilibrium of the terrain system including the moment of inertia and frictional torque in the bearings as well as the load torque resulting from the operation of the internal fan. The simulation study concerned the starting process of the machine under different values of the load. The influence of the supply voltage phase angle at the moment of start-up and the initial position of the rotor in relation to the stator was investigated. In order to calibrate the model, tests of the physical object were performed. The corrections introduced concerned the magnetization characteristics of the magnetic circuit. The results obtained confirm the correctness of the adopted strategy of testing the operational properties of the considered engine.

Effect of Flux Barrier Shape on Performance of Single-Phase Line Start Synchronous Reluctance Motor Modified from Single Phase Induction Motor

Effect of Flux Barrier Shape on Performance of Single-Phase Line Start Synchronous Reluctance Motor Modified from Single Phase Induction Motor

Rotor Design and Optimization of a Three-Phase Line-Start Synchronous Reluctance Motor

Three-phase line-start synchronous reluctance motor (LS-SynRM) is started by asynchronous torque generated by the rotor conductor bars, and runs synchronously by reluctance torque generated by the inductance difference. In this article, the rotor structure of an LS-SynRM is designed and optimized, based on the theory and characteristics of LS-SynRMs during starting and steady-state operation. First, the influence of the number of rotor flux barriers and the flux barriers ratio on the dq-axis inductance is simulated, and a better structure of rotor flux barriers is obtained. Second, according to the transient theory, a method of separating each torque during the starting process of LS-SynRMs is proposed, and the main reason for the poor starting ability of the initial LS-SynRM is analyzed. Based on the optimized structure of rotor flux barriers, the influence of the area and distribution of the rotor conductor bars on the starting ability of the LS-SynRM is studied, and the structure of rotor conductor bars under the condition of starting with heavy load (constant load) is determined. Finally, through the prototype test, the rated efficiency of the LS-SynRM is 2.8% higher than that of the SCIM is replaced by three phase squirrel cage induction motor (SCIM), which verifies the accuracy of the simulated results. At the same time, the starting current and the pull-in torque under a specific inertia are tested, and the improved effect of the synchronization ability of the improved LS-SynRM was verified.