scholarly journals The differential method of detecting coil circuitsfaults in three-phase transformer

2020 ◽  
Vol 22 (3) ◽  
pp. 78-89
Author(s):  
R. G. Mustafin ◽  
R. F. Yarish
Keyword(s):  
High Sensitivity ◽  
General Purpose ◽  
Differential Method ◽  
Differential Signal ◽  
Intact State ◽  
Three Phase ◽  
Voltage Phase ◽  
Differential Methods ◽  
Magnetic Resistance ◽  
Transformer Core

Idle voltages proportional to corresponding magnetic flows of three-phase transformer of general purpose are measured using differential methods aimed at detection of inter turn faultin windings of three-leg transformers.The standard method of determining the inter turn fault in the transformer windings is based on measuring idling current and measuring loss power. In addition, differential methods well known in relay protection are proposed to determine the presence of inter turn faultin three-phase linear transformers. The methods are based on the fact that the inter turn fault increases the magnetic resistance of the phase rod of the transformer core, in the phase winding of which there is a inter turn fault. When one-phase voltage is applied to the winding of phase B in the windings of side phases A and C of the linear three-phase transformer, the same voltage phase and amplitude shall be induced. When phase A and C windings are connected in opposition and differential signal is measured, voltage difference of phases A and C is as follows. If, in the original, intact state, the differential signal was close to zero, the inter turn faultin one of the side phases A or C introduces an imbalance and the differential signal increases. The differential signal is easily measured against the background of the near zero differential signal in the intact state of the transformer, which causes a high sensitivity of the differential method to the presence of inter turn fault. In case of a inter turn faulton the winding of the central phase B, it is necessary to take into account the differential signal in the intact state of the transformer.

Identificación de polaridad de los devanados en un motor trifásico de 6 terminales

2019 ◽  
pp. 13-19
Author(s):  
José Luis Viramontes-Reyna ◽  
Josafat Moreno-Silva ◽  
José Guadalupe Montelongo-Sierra ◽  
Erasmo Velazquez-Leyva
Keyword(s):  
Low Cost ◽  
Voltage Reference ◽  
Three Phase ◽  
Voltage Phase ◽  
The Law ◽  
And Control

This document presents the results obtained from the application of the law of Lens to correctly identify the polarity of the windings in a three-phase motor with 6 exposed terminals, when the corresponding labeling is not in any situation; Prior to identifying the polarity, it should be considered to have the pairs of the three windings located. For the polarity, it is proposed to feed with a voltage of 12 Vrms to one of the windings, which are identified randomly as W1 and W2, where W1 is connected to the voltage phase of 12 Vrms of the signal and W2 to the voltage reference to 0V; by means of voltage induction and considering the law of Lens, the remaining 4 terminals can be identified and labeled as V1, V2, U1 and U2. For this process a microcontroller and control elements with low cost are used.

scholarly journals Experimental Study of Various Parameters during Speed Control of Three-phase Induction Motor Using GPIC and LabVIEW

2021 ◽  
Vol 5 (1) ◽  
pp. 51-62
Author(s):  
Adnan Ahmed ◽  
Abdul Majeed Shaikh ◽  
Muhammad Fawad Shaikh ◽  
Shoaib Ahmed Shaikh ◽  
Jahangir Badar Soomro
Keyword(s):  
Induction Motor ◽  
Induction Motors ◽  
Induction Machine ◽  
Speed Control ◽  
Industrial Applications ◽  
General Purpose ◽  
Three Phase ◽  
Field Programmable ◽  
Input Source ◽  
Open Control

Induction motors are widely used from home to industrial applications. Speed of induction motor plays important role, so to control the speed of induction motor various techniques are adopted and one of these techniques is V/F control, which is adopted in this paper. This technique helps to control the speed in open control system in RPM. Moreover, Control is designed in LabVIEW, it is quite helpful to develop the circuit graphically and code is automatically written in the background to run on Field Programmable Gate Array (FPGA). The aim of this research is to study the impacts on diverse parameters during speed control of three phase induction machine with manipulation of GPIC. Solar technology is used as input source to drive the General-Purpose Inverter Controller (GPIC). Apart of this, impacts of modulation index and carrier frequency influencing the active, reactive and apparent power, temperature and power quality and current overshoot is analysed. MATLAB/Simulink and LabVIEW tools are used for simulation and results along with GPIC, Induction motor and solar panel as hardware.

scholarly journals Complex Electronic Protection for Low-voltage Three-phase Induction Motors

2020 ◽  
Vol 11 ◽  
pp. 11-17
Author(s):  
Gabriel Nicolae Popa ◽  
Corina Maria Diniș
Keyword(s):  
Induction Motors ◽  
Low Voltage ◽  
Short Circuit ◽  
Electronic Devices ◽  
General Purpose ◽  
Two Phase ◽  
Dc Voltage ◽  
Electric Drives ◽  
Normal Limits ◽  
Three Phase

Low-voltage three-phase induction motors are most often used in industrial electric drives. Electric motors must be protected by electric and/or electronic devices against: short-circuit, overloads, asymmetrical currents, two-phase voltage operation, under-voltage, and over-temperature. To design the electronic protection currents, voltages and temperature must be measured to determine whether they fall within normal limits. The electronic protection was design into low capacity PLC. The paper presents the designs and analysis of complex electronic protection for general purpose low-voltage three-phase induction motors. The electronic protection has Hall transducers and conversion electronic devices for AC currents to DC voltages, AC voltages to DC voltage, temperature to DC voltage, a low capacity PLC, switches, motor’s power contactors, and signalling lamps has been developed. Experiments with complex electronic protection, for different faults are presented. The proposed protection has the advantages of incorporating all usual protections future for the low-voltage three-phase induction motors.

scholarly journals New Stable Closed Newton-Cotes Trigonometrically Fitted Formulae for Long-Time Integration

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
T. E. Simos
Keyword(s):  
Time Integration ◽  
Differential Method ◽  
Algebraic Order ◽  
Long Time ◽  
Long Time Integration ◽  
Differential Methods

The closed Newton-Cotes differential methods of high algebraic order for small number of function evaluations are unstable. In this work, we propose a new closed Newton-Cotes trigonometrically fitted differential method of high algebraic order which gives much more efficient results than the well-know ones.

Building Factor of Grain-Oriented Silicon Iron (3% SiFe) with Different Thickness on 100kVA Three Phase Distribution Transformer Core

2012 ◽  
Vol 488-489 ◽  
pp. 537-541
Author(s):  
N. Ashbahani ◽  
I. Daut ◽  
Mohd Irwan Yusoff
Keyword(s):  
Power Loss ◽  
Phase Distribution ◽  
Operation Mode ◽  
Load Test ◽  
Core Material ◽  
Distribution Transformer ◽  
Silicon Iron ◽  
Three Phase ◽  
Transformer Model ◽  
Transformer Core

The power loss in laminated transformer cores is always greater than the nominal loss of the electrical steel laminations, by a factor known as the building factor. This paper discussed result of an investigation towards the effect of using two different Grain-Oriented Silicon Iron (3%SiFe) materials to the 100kVA three phase distribution transformer. The thicknesses of the material that have been used in this research are 0.23mm and 0.27mm. The transformer core will be assembled with 60o T-joint with 5mm mitred corner overlap length. Power loss has been measured using no-load test with 29 layer of lamination while nominal loss measured using Epstein test frame. At the operation mode flux density, 1.5T, the building factor of the transformer model core material with 0.23mm thickness is 1.219 while with the building factor for 0.27mm thickness is 1.250. This shows that thinner transformer core lamination is better than the other one by 2.5% during operation mode.

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