A Review of Transient Electrical Upsets in Induction Motors and Their Effects on Centrifugal Compressors

2013 ◽  
Author(s):  
Michael Moeller ◽  
Anand Srinivasan
Keyword(s):  
High Speed ◽  
Induction Motors ◽  
Selection Process ◽  
Global Strategy ◽  
Operating Conditions ◽  
Drive Train ◽  
Centrifugal Compressors ◽  
Two Phase ◽  
Industry Standards ◽  
Three Phase

For several decades in the process industry, critical plant operations demanding continuous run time have used high speed turbocompressors, most commonly driven by induction motors. Transient disturbances, caused by grid and motor-terminal upsets, are common occurrences in three-phase induction motors. Such upsets can arise during start-up as well as steady state operating conditions, and can have an impact on the driven equipment. Common upset conditions include startup line bursts, voltage unbalances, two-phase & three-phase short circuits, and bus-transfers & reclosures. These transient upsets not only impact the motor, but also have a torsional influence on the motor-compressor drive-train. Understanding the significance of these upsets, and how it impacts the driven equipment is thus an important part of machinery design and the component selection process for centrifugal compressors. This paper presents a qualitative approach to analyzing these transient conditions arising from induction motors, and the resulting effects on driven equipment such as centrifugal compressors. As the compression industry continues to develop into a globally integrated market, it becomes even more important to understand these effects; to ensure that a consistent global strategy exists to control these upsets and to mitigate some of the ill-effects resulting from torsional bursts on the drive train. A review of the current industry standards and mitigation techniques has also been presented.

scholarly journals Mutual Information and Meta-Heuristic Classifiers Applied to Bearing Fault Diagnosis in Three-Phase Induction Motors

2020 ◽  
Vol 11 (1) ◽  
pp. 314
Author(s):  
Gustavo Henrique Bazan ◽  
Alessandro Goedtel ◽  
Marcelo Favoretto Castoldi ◽  
Wagner Fontes Godoy ◽  
Oscar Duque-Perez ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Mutual Information ◽  
Induction Motors ◽  
Operating Conditions ◽  
Industrial Systems ◽  
Bearing Fault Diagnosis ◽  
Bee Colony ◽  
Three Phase ◽  
C4.5 Decision Tree ◽  
The Time Domain

Three-phase induction motors are extensively used in industrial processes due to their robustness, adaptability to different operating conditions, and low operation and maintenance costs. Induction motor fault diagnosis has received special attention from industry since it can reduce process losses and ensure the reliable operation of industrial systems. Therefore, this paper presents a study on the use of meta-heuristic tools in the diagnosis of bearing failures in induction motors. The extraction of the fault characteristics is performed based on mutual information measurements between the stator current signals in the time domain. Then, the Artificial Bee Colony algorithm is used to select the relevant mutual information values and optimize the pattern classifier input data. To evaluate the classification accuracy under various levels of failure severity, the performance of two different pattern classifiers was compared: The C4.5 decision tree and the multi-layer artificial perceptron neural networks. The experimental results confirm the effectiveness of the proposed approach.

Influence of Gas-Liquid Two-Phase Intermittent Flow on Hydraulic Sand Dune Migration in Horizontal Pipelines

2010 ◽  
Vol 132 (7) ◽  
Author(s):  
Afshin Goharzadeh ◽  
Peter Rodgers ◽  
Chokri Touati
Keyword(s):  
High Speed ◽  
Sand Dune ◽  
Front Velocity ◽  
Intermittent Flow ◽  
Sand Particle ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Particle Mobility ◽  
Three Phase ◽  
Gas Ratio

This paper presents an experimental study of three-phase flows (air-water-sand) inside a horizontal pipe. The results obtained aim to enhance the fundamental understanding of sand transportation due to saltation in the presence of a gas-liquid two-phase intermittent flow. Sand dune pitch, length, height, and front velocity were measured using high-speed video photography. Four flow compositions with differing gas ratios, including hydraulic conveying, were assessed for sand transportation, having the same mixture velocity. For the test conditions under analysis, it was found that the gas ratio did not affect the average dune front velocity. However, for intermittent flows, the sand bed was transported further downstream relative to hydraulic conveying. It was also observed that the slug body significantly influences sand particle mobility. The physical mechanism of sand transportation was found to be discontinuous with intermittent flows. The sand dune local velocity (within the slug body) was measured to be three times higher than the averaged dune velocities, due to turbulent enhancement within the slug body.

scholarly journals Faults diagnosis in stator windings of high speed solid rotor induction motors using fuzzy neural network

2021 ◽  
Vol 12 (1) ◽  
pp. 597
Author(s):  
Ahmed Thamer Radhi ◽  
Wael Hussein Zayer
Keyword(s):  
Neural Network ◽  
Equivalent Circuit ◽  
High Speed ◽  
Fuzzy Neural Network ◽  
Induction Motors ◽  
Stator Winding ◽  
Three Phase ◽  
Fuzzy Neural ◽  
Diagnosis Method ◽  
Faults Diagnosis

The paper deals with faults diagnosis method proposed to detect the inter-turn and turn to earth short circuit in stator winding of three-phase high-speed solid rotor induction motors. This method based on negative sequence current of motor and fuzzy neural network algorithm. On the basis of analysis of 2-D electromagnet field in the solid rotor the rotor impedance has been derived to develop the solid rotor induction motor equivalent circuit. The motor equivalent circuit is simulated by MATLAB software to study and record the data for training and testing the proposed diagnosis method. The numerical results of proposed approach are evaluated using simulation of a three-phase high-speed solid-rotor induction motor of two-pole, 140 Hz. The results of simulation shows that the proposed diagnosis method is fast and efficient for detecting inter-turn and turn to earth faults in stator winding of high-speed solid-rotor induction motors with different faults conditions

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.

Visualization of Supercritical Carbon Dioxide Flow Through a Converging-Diverging Nozzle

2019 ◽  
Author(s):  
Chang Hyeon Lim ◽  
Gokul Pathikonda ◽  
Sandeep Pidaparti ◽  
Devesh Ranjan
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Critical Point ◽  
High Speed ◽  
Operating Conditions ◽  
Higher Plant ◽  
Two Phase ◽  
Pressure Profiles ◽  
Flow Through ◽  
Supercritical Carbon

Abstract Supercritical carbon dioxide (sCO2) power cycles have the potential to offer a higher plant efficiency than the traditional Rankine superheated/supercritical steam cycle or Helium Brayton cycles. The most attractive characteristic of sCO2 is that the fluid density is high near the critical point, allowing compressors to consume less power than conventional gas Brayton cycles and maintain a smaller turbomachinery size. Despite these advantages, there still exist unsolved challenges in design and operation of sCO2 compressors near the critical point. Drastic changes in fluid properties near the critical point and the high compressibility of the fluid pose several challenges. Operating a sCO2 compressor near the critical point has potential to produce two phase flow, which can be detrimental to turbomachinery performance. To mimic the expanding regions of compressor blades, flow through a converging-diverging nozzle is investigated. Pressure profiles along the nozzle are recorded and presented for operating conditions near the critical point. Using high speed shadowgraph images, onset and growth of condensation is captured along the nozzle. Pressure profiles were calculated using a one-dimensional homogeneous equilibrium model and compared with experimental data.

scholarly journals Three-Phase Induction Motors Online Protection against Unbalanced Supply Voltages

Machines ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 203
Author(s):  
Khaled Laadjal ◽  
Mohamed Sahraoui ◽  
Abdeldjalil Alloui ◽  
Antonio J. Marques Cardoso
Keyword(s):  
Working Conditions ◽  
Reliable Method ◽  
Induction Motors ◽  
Operating Conditions ◽  
Common Condition ◽  
Industrial Facilities ◽  
Industrial Plants ◽  
Severity Estimation ◽  
Three Phase ◽  
Supply Voltages

Three-phase induction motors (IMs) are the main workhorse in industry due to their many advantages as compared to other types of industrial motors. However, the efficiency and lifetime of IMs can be considerably affected by some operating conditions, in particular those related to unbalanced supply voltages (USV), which is quite a common condition in industrial plants. Therefore, early detection and a precise severity estimation of the USV for all working conditions can prevent major breakdowns and increase reliability and safety of industrial facilities. This paper proposes a reliable method allowing for a precise and online detection of the USV condition, by monitoring a pertinent indicator calculated using the voltage symmetrical components. The effectiveness of the proposed method is validated experimentally for several different working conditions, and a comparison with other indicators available in the literature is also performed.

Two-Phase Emergency Feeding of Three-Phase Induction Motors

2004 ◽  
Vol 37 (14) ◽  
pp. 495-500
Author(s):  
Ludek Schreier ◽  
Miroslav Chomat ◽  
Jiri Bendl ◽  
jiri Klima
Keyword(s):  
Induction Motors ◽  
Two Phase ◽  
Three Phase

Experimental Characterization of the Flow Instabilities of a Mixed-Flow Multiphase Pump Operating Air and Water Through Local Visualization and Analysis of Dynamic Measurements

2015 ◽  
Author(s):  
Alberto Serena ◽  
Lars E. Bakken
Keyword(s):  
High Speed ◽  
Numerical Models ◽  
Operating Conditions ◽  
Test Facility ◽  
Two Phase ◽  
Flow Mechanisms ◽  
Local Measurements ◽  
Specific Geometry ◽  
Promising Development

Part load operation of pumps generates flow and machine instabilities, which are not desirable and should be avoided as they result in premature wear and mechanical problems. Two-phase flow introduces additional challenges, both at the design and operational stages, due to the different phase behavior and mutual interaction. The phenomena involved present an intermittent character and are strongly dependent on the specific geometry and operating conditions. Despite the recent promising development of numerical simulations capabilities, an accurate characterization of the flow mechanisms still relies on real tests, which are needed to validate the numerical models too. An advanced laboratory test facility built at the Norwegian University of Science and Technology provides the required optical access to the pump channels, and high-speed recordings, along with local measurements of the pressure pulsations, allow to describe the flow structures in terms of location, length and time scales, and relate them to overall machine measurements, such as flow, pressure and torque. This provides a wide collection of test data of great value for a further understanding of the surging phenomenon, the development of a surging onset prediction model and a control strategy. Tests are performed covering the whole range of flow rates; a characteristic surging condition is identified and described in the article.

scholarly journals Efficient Preparation of Bafilomycin A1 from Marine Streptomyces lohii Fermentation Using Three-Phase Extraction and High-Speed Counter-Current Chromatography

Marine Drugs ◽  
2020 ◽  
Vol 18 (6) ◽  
pp. 332
Author(s):  
Ye Yuan ◽  
Xiaoping He ◽  
Tingting Wang ◽  
Xingwang Zhang ◽  
Zhong Li ◽  
...  
Keyword(s):  
Crude Extract ◽  
High Speed ◽  
Solvent System ◽  
Bafilomycin A1 ◽  
Middle Phase ◽  
Two Phase ◽  
Rapid Separation ◽  
Lower Phase ◽  
Three Phase ◽  
Counter Current

An efficient strategy was developed for the rapid separation and enrichment of bafilomycin A1 (baf A1) from a crude extract of the marine microorganism Streptomyces lohii fermentation. This strategy comprises liquid−liquid extraction (LLE) with a three-phase solvent system (n-hexane–ethyl acetate–acetonitrile–water = 7:3:5:5, v/v/v/v) followed by separation using high-speed counter-current chromatography (HSCCC). The results showed that a 480.2-mg fraction of baf A1-enriched extract in the middle phase of the three-phase solvent system was prepared from 4.9 g of crude extract after two consecutive one-step operations. Over 99% of soybean oil, the main hydrophobic waste in the crude extract, and the majority of hydrophilic impurities were distributed in the upper and lower phase, respectively. HSCCC was used with a two-phase solvent system composed of n-hexane–acetonitrile–water (15:8:12, v/v/v) to isolate and purify baf A1 from the middle phase fraction, which yielded 77.4 mg of baf A1 with > 95% purity within 90 min. The overall recovery of baf A1 in the process was determined to be 95.7%. The use of a three-phase solvent system represents a novel strategy for the simultaneous removal of hydrophobic oil and hydrophilic impurities from a microbial fermentation extract.

Bubble Behaviour in Three Phase Capillary Microreactors

2003 ◽  
Vol 1 (1) ◽  
Author(s):  
Mark J Simmons ◽  
David C Y Wong ◽  
Paul J Travers ◽  
James S Rothwell
Keyword(s):  
High Speed ◽  
Flow Characteristics ◽  
Flow Regimes ◽  
Two Phase ◽  
Microchannel Reactors ◽  
Flow Maps ◽  
Three Phase ◽  
Monolith Reactors ◽  
Produce Flow ◽  
Churn Flow

Two-phase flow characteristics in vertical capillary downflow were investigated in order to obtain understanding of the behaviour of three-phase monolith reactors. Experiments were conducted using air and dyed water in round and square capillary tubes of 2 mm and 3 mm diameter. The flow regimes and transitions observed were recorded using high speed videography and this data was used to produce flow maps for each tube. The gas and liquid superficial velocities used ranged from 0.001 to 10 m/s and 0.0001 to 1 m/s respectively. The flow regimes and their transitions were found to be a strong function of tube geometry and surface tension effects, and some differences were observed between capillaries of round and square section. This has significant implications for the design of microchannel reactors. Annular, slug-annular, slug, bubbly and churn flow regimes were observed in the round tubes; channelling/irregular flow was observed in the square tubes in place of annular and slug-annular flow.

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