Application of standard and modified Eh-Star test method for induction motor stray load losses and efficiency measurement

The aim of this paper is to present the application of one simple and accurate method for the measurement of stray load losses (additional load losses) in induction machines. That is the Eh-Star method given in the IEC 60034-2-1 standard. In this paper the theoretical background of the method and the measurement procedure have been explained. All measurements have been performed using modern measurement systems based on a personal computer, data acquisition cards and LabVIEW software. According to the measured results for the stray load losses, the efficiency of the induction motor has been calculated. The efficiency obtained has been compared with the IEC standard efficiency classes, in order to determine the efficiency class of the tested motor. Additionally, measurements have been performed using the modified Eh-Star method. The results obtained have been compared with those obtained using the Eh-Star method. The advantages and disadvantages of both methods have been analyzed in this paper.

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Development of Detection Platform for Grid-Connected Photovoltaic Inverters

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.241-244.145 ◽

2012 ◽

Vol 241-244 ◽

pp. 145-148

Author(s):

Tao Yong Li ◽

Hua Guang Yan ◽

Jin Hui Xue ◽

Jin Ping Du

Keyword(s):

Detection System ◽

Power Grid ◽

Practical Application ◽

Computer Data ◽

Labview Software ◽

Testing Method ◽

Software Interface ◽

Computer Data Acquisition ◽

Control Computer ◽

Development Course

To ensure both performance and security of grid-connected photovoltaic inverters(PVI), a detection platform for grid-connected PVI is researched. The testing method and procedures of grid-connected PVI are analyzed and the development course of this detection platform is described in detail. The detection platform consists of control computer, data acquisition system, RS 485 and GPIB system. In this platform, the solar-cell panel is simulated by programmable DC source, the power grid characteristics of power grid by programmable DC source and the load characteristic by programmable controlled RLC load. The whole detection system is controlled by LabVIEW software interface. The proposed detection platform can be used in the testing of electric performance, protection function, EMC and so on. Practical application shows that the configuration of this detection platform is rational and reliable，and its detection results are accurate.

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Synchronized Diagnosis of Laser-Pulse MAG Hybrid Arc Based on Multi-Information

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.494-495.865 ◽

2014 ◽

Vol 494-495 ◽

pp. 865-868

Author(s):

Ying Gao ◽

Jing Hua Han ◽

Li Yan Lou

Keyword(s):

Information Acquisition ◽

High Speed ◽

Hybrid Welding ◽

Computer Data ◽

Labview Software ◽

Effect Mechanism ◽

Welding Technology ◽

Computer Data Acquisition ◽

Data Acquisition Card ◽

Peak Value

Laser-Arc Hybrid welding technology was first introduced by English scholar W.M.Steen in 20th century 70s, developed very rapidly. In order to study the effect mechanism of laser and arc,This paper presents a control strategy,the strategy can collect welding electric information, high speed photos and spectral information synchronously. By using the Labview software, industrial computer, data acquisition card, a high speed camera, spectrometer, synchronous multi-information acquisition system of welding has been established.the system has been used for the hybrid welding experiment, the peak value, base value and platform value of the laser-arc hybrid welding has been collected. Laid the foundation for further diagnosis of laser-arc in a variety of state.

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Perbandingan Expanded Curb-65 Terhadap Curb-65 dan Psi Dalam Memprediksi Luaran Pasien Cap

Jurnal Endurance ◽

10.22216/jen.v4i3.4916 ◽

2019 ◽

Vol 4 (3) ◽

pp. 608

Author(s):

Suyastri Suyastri ◽

Irvan Medison ◽

Deddy Herman ◽

Russilawati Russilawati

Keyword(s):

Logistic Regression ◽

Multivariate Analysis ◽

Prospective Study ◽

Pneumonia Severity Index ◽

Severity Index ◽

Accurate Method ◽

P Value ◽

Pneumonia Severity ◽

Advantages And Disadvantages ◽

Care Decision

Tingkat keparahan CAP adalah poin penting pengambilan keputusan perawatan pasien. Beberapa metode telah digunakan untuk menilai tingkat keparahan pneumonia seperti Pneumonia Severity Index (PSI), CURB-65, SMART-COP dan Expanded CURB-65. Metode tersebut memiliki kelebihan dan kekurangan. Expanded CURB 65 diusulkan menjadi metode yang lebih akurat untuk mengevaluasi keparahan pneumonia dan memprediksi kematian pasien CAP. Tujuan penelitian ini memprediksi keakuratan Expanded CURB 65 dibandingkan CURB 65 dan PSI. Penelitian kohort prospektif pada pasien CAP yang dirawat di RSUP Dr. M.Djamil Padang dari April sampai Oktober 2019. Tingkat keparahan CAP pada pasien dinilai menggunakan PSI, CURB 65, Expanded CURB 65, kemudian hasilnya dievaluasi berdasarkan keparahan. Data dianalisis menggunakan regresi logistik dengan CI 95% dan nilai p <0,05 dianggap signifikan. Hasil penelitian pada 90 pasien sebagian besar laki-laki usia 53 tahun dengan komorbiditas terbanyak keganasan. Uji Pearson Chi aquare menunjukkan tidak ada hubungan antara tingkat keparahan berdasarkan CURB 65 dan luaran pengobatan (CI 95%, nilai p = 0,104). Sementara, PSI dan Expanded CURB 65 memiliki hubungan yang signifikan antara tingkat keparahan dan luaran (CI 95%, p=0,081 dan CI 95%, p= 0,046, masing-masing). Analisis multivariat menemukan Expanded CURB 65 lebih akurat dalam memprediksi luaran pasien CAP rawat inap (kappa =0,108 dan AUC=0,422). Severity of CAP is very important for site care decision inpatients. Several methods have been used to assess the severity of pneumonia such as Pneumonia Severity Index (PSI), CURB-65, SMART-COP and Expanded CURB-65. Those methods have advantages and disadvantages. Expanded CURB 65 is proposed to be more accurate method for evaluating pneumonia severity and predicting mortality in CAP. The aim of this study was to investigate the accuracy of Expanded CURB 65 compare to CURB 65 and PSI. Cohort prospective study was conducted for CAP patients who were hospitalized at RSUP Dr. M.Djamil Padang from April to October 2019. Patients was assesed for severity using PSI, CURB 65, Expanded CURB 65, then we evaluated it’s outcome. The data were analyzed by logistic regression with CI 95% and p value <0,05 considered as statistically significant. We found 90 patients that predominantly males with an average age of 53 years, and the most common comorbidity is malignancy. There was no relationship between pneumonia severity by CURB 65 and outcome (CI 95%, p=0.104). PSI and Expanded CURB 65 had significant relationship between severity and outcome (CI 95%, p=0.081and CI 95%, p=0.046, respectively). Multivariate analysis showed the expanded CURB 65 was more accurate for predicting the outcome of CAP inpatients (kappa=0.108 and AUC= 0.422).

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A New Approach for Non-Linear Time-Harmonic FEM-Based Analysis of Single-Sided Linear Induction Motor Incorporated with a New Accurate Method of Force Calculation

IEEE Transactions on Magnetics ◽

10.1109/tmag.2020.3040720 ◽

2020 ◽

pp. 1-1

Author(s):

A. Zare-Bazghaleh ◽

E. Fallah-Choolabi

Keyword(s):

Induction Motor ◽

Linear Time ◽

Accurate Method ◽

New Approach ◽

Linear Induction ◽

Linear Induction Motor ◽

Time Harmonic ◽

Non Linear ◽

Force Calculation

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Analysis of the Test Method of Quartz Glass Optical Homogeneity

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.726.414 ◽

2017 ◽

Vol 726 ◽

pp. 414-418

Author(s):

Bo Fu ◽

Hui Wang ◽

Zhu Feng Shao

Keyword(s):

Quartz Glass ◽

Measurement Accuracy ◽

Test Methods ◽

Test Method ◽

Wavefront Aberration ◽

Optical Homogeneity ◽

Advantages And Disadvantages ◽

Interference Measurement ◽

Optical Quartz Glass

The optical quartz glass is widely applied in optical system , photo communications，inertial navigation，etc.It must have high optical homogeneity. Optical homogeneity of the optical quartz glass directly affects the wavefront quality of the optical transmission system, and changes the wavefront aberration of the system. How to accurately determine the optical homogeneity of the quartz glass is especially important. Currently，the method of test for optical homogeneity mainly used by interference principle. This paper analyzes various existing interference measurement method and test equipment. Summarized the advantages and disadvantages of various test methods，using range and measurement accuracy.

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Inexpensive computer data‐acquisition system

Review of Scientific Instruments ◽

10.1063/1.1138407 ◽

1985 ◽

Vol 56 (10) ◽

pp. 1972-1972 ◽

Cited By ~ 3

Author(s):

James E. Galvin ◽

Ian G. Brown

Keyword(s):

Data Acquisition ◽

Data Acquisition System ◽

Acquisition System ◽

Computer Data ◽

Computer Data Acquisition

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Effect of Light Exposure Conditions on the Light-Induced Degradation in Amorphous Silicon Alloy Solar Cells

MRS Proceedings ◽

10.1557/proc-219-433 ◽

1991 ◽

Vol 219 ◽

Cited By ~ 2

Author(s):

Y. Nakata ◽

A. Yokota ◽

H. Sannomiya ◽

S. Moriuchi ◽

Y. Inoue ◽

...

Keyword(s):

Solar Cells ◽

Light Exposure ◽

Analytical Formula ◽

Theoretical Background ◽

Test Method ◽

Exposure Condition ◽

Solar Simulator ◽

Silicon Alloys ◽

Normalized Parameters ◽

Photovoltaic Parameters

ABSTRACTLight-induced changes in current-voltage characteristics of amorphous single-junction solar cells made of silicon alloys, a-SiC, a-Si, and a-SiGe have been studied systematically. The effect of the light intensity and the bias voltage on the light-induced degradation in the conversion efficiency and other photovoltaic parameters has been clarified quantitatively, and it has been shown that the light-induced degradation characteristics of the photovoltaic parameters can be described by a single function of some normalized parameters of exposure condition. Theoretical background for the experimental results is also examined and discussed by applying a defect creation model modified to an active layer of the a-Si alloy solar cells. Utilizing these analytical formula, we propose an accelerated test method by solar simulator indoor measurement instead of natural sunlight outdoor testing.

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Computer Applications at the Institute for Thermal Turbomachinery (Its): Integration of Personal Computer Data Acquisition Systems in a Local Area Network

Hector ◽

10.1007/978-3-642-73576-9_30 ◽

1988 ◽

pp. 240-250

Author(s):

S. Wittig ◽

K.-H. Platzer ◽

W. Januszewski ◽

M. Lehner

Keyword(s):

Data Acquisition ◽

Personal Computer ◽

Local Area Network ◽

Local Area ◽

Computer Applications ◽

Area Network ◽

Computer Data ◽

Data Acquisition Systems ◽

Computer Data Acquisition

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Computer Simulation of Partial Discharges in Voids inside Epoxy Resins Using Three-Capacitance and Analytical Models

Polymers ◽

10.3390/polym12010077 ◽

2020 ◽

Vol 12 (1) ◽

pp. 77 ◽

Cited By ~ 4

Author(s):

Johnatan M. Rodríguez-Serna ◽

Ricardo Albarracín-Sánchez ◽

Ming Dong ◽

Ming Ren

Keyword(s):

Epoxy Resins ◽

Circuit Simulation ◽

Electric Circuit ◽

Real Data ◽

Theoretical Background ◽

General Purpose ◽

Partial Discharges ◽

Analytical Models ◽

Advantages And Disadvantages ◽

Capacitance Model

Epoxy resin is one of the most common polymers used as part of the insulation system in key electrical assets such as power transformers and hydrogenerators. Thus, it is necessary to know their main characteristics and to evaluate their condition when subjected to High Voltage (HV). A brief review of epoxy resins’ applications as insulating materials is made, their main characteristics as insulating media are given, the improvements with nano-fillers are summarized and the main electric properties required for Partial Discharges (PD) modelling are listed. In addition, the theoretical background and state-of-the-art of the three-capacitance and analytical models for simulating PD in solid dielectrics, such as epoxy resins, are reviewed in detail. Besides, their main advantages and disadvantages are presented, some critical arguments to the modelling procedure and assumptions are made and some improvements are proposed, taking into account conclusions made from other authors using models related to the PD development process. Finally, a case study was simulated using a modified three-capacitance model and the analytical model. The PD rate, q-φ-n diagrams and the minimum, mean and maximum PD electric charge are compared with measurements reported in the literature. Simulation results are in reasonable agreement with measured values. Capacitance models can be implemented in general purpose electric circuit simulation packages; however, its simulation is computationally expensive. Additional to this, although the modified three-capacitance model is not as accurate as finite elements or analytical models, results are also in agreement with real data.

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