Design of Self-Starting Hybrid Axial Flux Permanent Magnet Synchronous Motor Connected Directly to Line

Eker, Mustafa,Akar, Mehmet,Emeksiz, Cem,Dogan, Zafer,Fenercioglu, Ahmet The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.5

In view of the current state of the reserves of electric energy generated resources and the share of electric motors in electricity consumption, many researches and studies related to efficiency in electric motors are being made. The presented work is related to the Axial Flux Permanent Magnet Synchronous Motor (AF-PMSM), which has recently undergone significant work based on the development of magnet and motor technology. In this study, a novel AF-PMSM was designed analytically through Finite Element Method (FEM) which can be started by connecting to a line such as an asynchronous motor in a transient state and can operate with high efficiency and power factor after synchronization in steady state without the need for an expensive motor drive. According to the obtained FEM results, a design with an efficiency class of IE4 of 5.5 kW shaft power, a 4 poles motor was obtained. As a result, economic calculations indicate that the extra cost of the designed Line start AF-PMSM with respect to the asynchronous motor is rapidly compensated by energy saving due to a more efficient operation, especially constant speed operations. As a result of the analysis obtained, the targeted values are reached. For induction motors and radial flux permanent magnet synchronous motors, a good alternative motor that can operate with high efficiency and power factor has been obtained.

Design of Self-Starting Hybrid Axial Flux Permanent Magnet Synchronous Motor Connected Directly to Line

Mustafa Eker,Mehmet Akar,Cem Emeksiz,Zafer Dogan,Ahmet Fenercioglu 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.5

In view of the current state of the reserves of electric energy generated resources and the share of electric motors in electricity consumption, many researches and studies related to efficiency in electric motors are being made. The presented work is related to the Axial Flux Permanent Magnet Synchronous Motor (AF-PMSM), which has recently undergone significant work based on the development of magnet and motor technology. In this study, a novel AF-PMSM was designed analytically through Finite Element Method (FEM) which can be started by connecting to a line such as an asynchronous motor in a transient state and can operate with high efficiency and power factor after synchronization in steady state without the need for an expensive motor drive. According to the obtained FEM results, a design with an efficiency class of IE4 of 5.5 kW shaft power, a 4 poles motor was obtained. As a result, economic calculations indicate that the extra cost of the designed Line start AF-PMSM with respect to the asynchronous motor is rapidly compensated by energy saving due to a more efficient operation, especially constant speed operations. As a result of the analysis obtained, the targeted values are reached. For induction motors and radial flux permanent magnet synchronous motors, a good alternative motor that can operate with high efficiency and power factor has been obtained.

Effect of demagnetization faults on line start AF‑PMSM performance

Mustafa Eker,Mustafa Ozsoy 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.6

This study is concerned with irreversible demagnetization faults in axial fl ux permanent magnet synchronous motors (AFPMSM). Line start capability was provided to the AF-PMSM by making changes in its traditional rotor architecture. With this architecture, the motor operates as an asynchronous motor in the transient state and as a synchronous motor in the steady state. In this study, the impacts of an irreversible demagnetization fault on motor performance, which occurs in motors due to various reasons, is investigated. The four poles of the used AF-PMSM have 5.5 kW of shaft power. Each pole is comprised of fi ve identical magnets. Diff erent rates (20%, 40%, and 60%) of demagnetization failure were created in a single pole. The data acquired from the faulty motors were compared to data from a healthy motor. The results indicate that irreversible demagnetization faults have an adverse impact on motor performance. It was observed that the experimentally created demagnetization faults increase the current drawn by the motor. In addition, they cause a decrease in both the power factor and effi ciency. However, the faults did not have an adverse impact on the starting capability of the motor. The unique aspect of the present study is that it is the fi rst time the impacts of demagnetization faults on the performance of line start AF-PMSMs have been examined.

Neutrophil to Lymphocyte Ratio Predicts Left Ventricular Remodeling in Patients with ST Elevation Myocardial Infarction treated with Primary Percutaneous Intervention

Abdurrezzak Börekçi,Mustafa Gür,Caner Türkoğlu,Ahmet Oytun Baykan,Taner Şeker,Durmuş Yıldıray Şahin,Hazar Harbalıoğlu,Zafer Elbasan,Mustafa Topuz,Murat Çaylı 대한심장학회 2016 Korean Circulation Journal Vol.46 No.1

Background and Objectives: It has been demonstrated that the neutrophil/lymphocyte ratio (NLR) might be a useful marker to predict cardiovascular risk and events. We aimed to investigate the role of the NLR to predict ventricular remodeling (VR) in patients with anterior ST-elevation myocardial infarction (STEMI) who were treated with primary percutaneous coronary intervention. Subjects and Methods: We prospectively included 274 consecutive anterior STEMI patients. Echocardiography was performed during admission and at six months after myocardial infarction. VR was defined as at least 20% increase from baseline in left ventricular end- diastolic volume. Patients were divided into two groups according to their VR status: VR (n=67) and non-VR (n=207). Total and differential leukocyte count, N-terminal pro-brain natriuretic peptide (NT-proBNP) and other biochemical markers were measured at admission and 24 hours later. Results: Compared with the non-VR group, peak creatine kinase MB (CK-MB), NT-proBNP (24 h), neutrophil/lymphocyte ratio, presence of diabetes, no-reflow frequency and wall motion score index were significantly higher in patients with VR (p<0.05 for all). On multivariate logistic regression analysis, NLR (β=2.000, 95% confidence interval=1.577-2.537, p<0.001) as well as peak CK-MB, NT-proBNP (24 h), WMSI and diabetes incidence were associated with VR. The cutoff value of the neutrophil/lymphocyte ratio obtained by receiver operator characteristic curve analysis was 4.25 for the prediction of VR (sensitivity: 79 %, specificity: 74%). Conclusion: In patients with anterior STEMI, initial NLR and NT-proBNP measured 24 hours after admission may be useful for predicting adverse cardiovascular events including left VR.

Multislice Analysis of Axial Flux Synchronous Reluctance Motor Based on 2d Finite Element Method Linear Model

Emre Gözüaçık,Mustafa Eker,Mehmet Akar 한국자기학회 2023 Journal of Magnetics Vol.28 No.2

This study proposes a solution to improve the analysis time of the Axial Flux Synchronous Reluctance Motor (AF-SynRM) using the Finite Element Method (FEM) using the Finite Element Method (FEM). While accurate results can be achieved through 2D and 3D FEM analyses in the design of electrical machines, the analysis time becomes a significant consideration. The non-axisymmetric structure of the flux path in axial flux motors poses challenges for accurate results in 2D FEM analyses. To overcome this issue, the study uses simulation studies to convert axial flux motors into 2D linear models. In this study, a slice model approach is implemented in the linear structure, and the influence of the number of slices on various motor parameters, such as torque, torque ripple, back-EMF, loss, and efficiency, is analyzed and compared with 3D FEM analyses. Experimental loss and efficiency results are also included in these analyses. This study is the first to simulate an AF-SynRM in the 2D linear model. The accuracy of the results is verified experimentally.

The protective effect of Myrtus communis L. against experimental kidney stone in rats

Halil Yılmaz,Nihat Ekinci,Ayşe Ömerli,Mehtap Nisari,Arzu Hanım Yay,Harun Ülger,Karatoprak Gökçe Şeker,Seher Yımaz,Şükrü Ateş,Mustafa aştan 경희대학교 융합한의과학연구소 2023 Oriental Pharmacy and Experimental Medicine Vol.23 No.1

The aim of this study is to investigate the protective effect of 70% methanolic extract of Myrtus communis L. leaves (300 mg/kg) against the kidney stone modeling created by (0.75%) ethylene glycole. Twenty-eight, 10 week’s Sprague Dawley male rats were divided into four groups (n = 7) as the control group, ethylene glycol (EG) group, M. communis (MC) group and protective (EG + MC) group. For 28 days, while 0.75% EG was given by adding it to drinking water to occur kidney stone model, MC was given by gavage to test the protective effect. 24 h’ urine samples were taken, and calcium, creatinine, uric acid, magnesium, citrate and oxalate were evaluated. On the 28th day, the rats were sacrificed, and their kidneys were removed. Kidney tissues were examined with hematoxylin eosin (HE) staining and kidney stones formed with Pizzolato’s (PZ) staining technique were shown. M. communis extract brought abnormal urine parameter values closer to the control group. Additionally, it was concluded that the tissue degeneration and number of stones decreased in the protective group. M. communis extract has a protective effect against the kidney stone modeling which created by EG.