scholarly journals Research of remote protection operation in a branched sectioned line 10 kV

2020 ◽  
pp. 39-49
Author(s):  
A. Omelchuk ◽  
◽  
Y. Yarosh ◽  
V. Pryadko ◽  
O. Mashchenko ◽  
...  
Keyword(s):  
Short Circuit ◽  
Operating Time ◽  
Operation Time ◽  
Operating Conditions ◽  
Initial Time ◽  
Operating Modes ◽  
The Difference ◽  
The One ◽  
Percent Accuracy ◽  
Time Of Operation

The article investigates the parameters of setting up adjacent remote protections with remote start-up, taking into account the peculiarities of operating modes and operating conditions of partitioned branched distribution lines. The influence of parameters and modes of operation of such lines on the range of adjustment of settings on resistance and time of operation at the end of a zone of action and requirements to linearity of time characteristics that allows to define distances to a place of short circuit on operation time is defined. The results for setting up remote protections of partitioned lines with sources of distributed generation are obtained: the conditions for adjusting the protection settings for resistance to operation are determined taking into account the parameters of the partitioned lines and the limits of adjusting the settings for resistance to secondary values are determined. The conditions for adjusting the settings by the time of operation and the limits of the time of operation of protection for most lines are determined. For selective operation of protection at the selected settings on time of operation unambiguity of time characteristics at change of sizes of working currents of protection on condition of ten percent accuracy of work of protection on resistance of operation is provided. The conditions for ensuring the selective operation of adjacent protections in the selected range of settings by the time of operation, taking into account the ratio of resistances and the difference in the time of operation are determined. The initial time of protection protection is substantiated for debugging of protection on time of operation against operation of overvoltage limiters and against burnout of fusible insert of fuses of branches and unsoldering at short circuit directly behind the fuse. The use of modern microprocessor protection devices will ensure, on the one hand, the accuracy of the resistance, linear and unambiguous dependence of the operating time on the resistance of the short circuit at different levels of currents and voltages, etc., and on the other hand - ease of maintenance.

scholarly journals A Method for the Analysis of Interference from DME to ATCRBS in the Time Domain

Electronics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 393 ◽  
Author(s):  
Guofeng Jiang ◽  
Yangyu Fan ◽  
Hongbo Yuan ◽  
Pengliang Yuan
Keyword(s):  
Time Domain ◽  
Traffic Control ◽  
Initial Time ◽  
Analysis Method ◽  
Operating Modes ◽  
The Monte Carlo Method ◽  
The Difference ◽  
The Time Domain ◽  
Overlap Method ◽  
Recurrence Frequency

Analysis of the coexistence of two or more types of equipment is increasingly important. However, at present studies on the analysis method in the time domain are scant. Therefore, the aim of this paper is to explore the characteristics of signals and relations between interfering and desired signals in the time domain. Based on the periodicity of a signal, this paper presents a Periodic Pulse Overlap Method (PPOM). Using PPOM to analyze the interference from Distance Measuring Equipment (DME) to Air Traffic Control Radar Beacon System (ATCRBS) in the time domain, we obtain almost the same result as that based on the Monte Carlo Method (MCM). Furthermore, we discover the measures to reduce or even avoid interference, such as changing the Pulse Recurrence Frequency (PRF), adjusting the difference of initial time, and switching the operating modes of the equipment.

Effect of light switch illumination on total energy consumption

2021 ◽  
Vol 14 (2) ◽  
pp. 151-156
Author(s):  
M. A. Pronin ◽  
E. V. Churkina
Keyword(s):  
Energy Consumption ◽  
Power Consumption ◽  
Operating Time ◽  
Operation Time ◽  
Luminous Flux ◽  
Total Energy Consumption ◽  
Network Operation ◽  
The Difference ◽  
Standby Mode ◽  
Effect Of Light

The question of the relevance of reducing energy consumption is considered. An assumption is made that in cases where indoor illuminated switches are used that control a group of lamps, currents of the order of microamperes flow in the lighting network in the switched-off mode.The regulatory documentation related to the normative indicators of illumination as well as the typical area of premises is analyzed, and on the basis of the listed data, the calculation of the minimum required luminous flux emitted by lamps is made. The normalized calculated luminous flux was divided by the luminous flux from one lamp, with the resulting ratio rounded up. This ratio is the approximate number of lamps. This number of lamps will enable to calculate the total current of the entire lighting network.The standard rates for the operating time of the lighting network are taken into account. The operating time of the lighting network in the "standby" mode is the difference between the total number of hours per day and the standard operating time of the lighting network.Knowing the power consumption and the network operation time in the "standby" mode, we can calculate the power consumption of the lighting network in the "standby" mode.

scholarly journals Analysis of Control Methods for the Traction Drive of an Alternating Current Electric Locomotive

Symmetry ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 150
Author(s):  
Sergey Goolak ◽  
Viktor Tkachenko ◽  
Pavol Šťastniak ◽  
Svitlana Sapronova ◽  
Borys Liubarskyi
Keyword(s):  
Vector Control ◽  
Short Circuit ◽  
Asynchronous Motor ◽  
Torque Ripple ◽  
Operating Conditions ◽  
Control Methods ◽  
Electric Locomotive ◽  
Traction Drive ◽  
Operating Modes ◽  
Traction Drives

The analysis of operating conditions of traction drives of electric locomotives with asynchronous traction motors has been carried out. It was found that during operation in the output converter of an asynchronous motor, defects may occur, which leads to asymmetric modes of its operation. Models of a traction drive of an electric locomotive with asynchronous motors with scalar and vector control of the output converter are proposed, taking into account asymmetric operating modes. As a result of the simulation, the starting characteristics of the traction drive were obtained for various control methods both in normal and emergency modes of the drive. For the drive-in emergency mode, the following cases were investigated: the balance of the converter output voltages and the turn-to-turn circuit of 10% of phase A winding of the motor stator; imbalance of the output voltages of the inverter and an intact motor; imbalance of the output voltages of the converter and interturn short circuit of 10% of phase A winding of the motor stator. Comparison of the simulation results have shown that in emergency modes in the traction drive, the torque ripple on the motor shaft in the drive with vector control is 13% less, and in scalar control, the phase current unbalance coefficient is 22% less. The results of this work can be used to study the influence of the output converter control methods on the energy efficiency indicators of the traction drive of an AC electric locomotive.

scholarly journals Development of Automatic Accumulating Equipment for Roller-Type Onion Pot-Seeding Machine

2019 ◽  
Vol 9 (10) ◽  
pp. 2139
Author(s):  
Seok-Joon Hwang ◽  
Ju-Seok Nam
Keyword(s):  
Labor Force ◽  
Operating Time ◽  
Conveyor Belt ◽  
Operating Conditions ◽  
Factorial Experiment ◽  
The One ◽  
Multiple Stages

In this study, an automatic accumulating equipment for a roller-type onion pot-seeding machine was developed. The developed accumulating equipment accumulates the pot trays that complete the seeding in multiple stages using a conveyor belt and elevator plate, and can be easily attached to the existing roller-type onion pot-seeding machines as it is fabricated as a module. The components were selected to meet the conditions required for the accumulating equipment. A factorial experiment was performed by setting the transport speed of the conveyor belt and the one-time operating time of the actuator as test factors. Through the experiment, appropriate operating conditions to minimize the seed bounce rate in the accumulating process were derived. If the developed accumulating equipment is applied to a roller-type onion pot-seeding machine, the labor force and labor load required for seeding will be reduced.

Operating Performance and Wear Investigations of Brush Seals for Steam Turbine Applications

2013 ◽  
Author(s):  
M. Raben ◽  
H. Schwarz ◽  
J. Friedrichs
Keyword(s):  
Operating Performance ◽  
Operating Time ◽  
Operation Time ◽  
Operating Conditions ◽  
Live Steam ◽  
Test Facility ◽  
Measurement Unit ◽  
Test Rig ◽  
Brush Seal ◽  
Brush Seals

In recent years brush seals have become more and more an established alternative to existing labyrinth seals due to their increased pressure difference capability per stage in combination with a radial adaptive characteristic. In general brush seal and shaft should be in a concentric position. To utilize the special advantages of a brush seal system the radial adaptive capability of the seal’s bristle pack has to be achieved and guaranteed for the entire operation time. Every mechanism leading to a contact between the rotor and the seal will potentially cause an abrasive wear on both sides. In order to reduce this wear and to improve the operating performance of the brush seal, the influencing parameters resulting from the rotor eccentricity, the thermal gradient and the blown down characteristic of the bristle pack itself have to be understood. For this purpose the TU Braunschweig developed a unique steam test rig for brush seal investigations which allows live steam operations of single and multi stage brush seals up to 50 bar and 450 °C. Equipped with a 300 mm motor driven shaft, long time endurance tests under varying, transient operating conditions can be carried out. In addition to the steam test rig a second cold air test facility with an optical access and a force-displacement measurement unit is used. To analyse the operating bristle pack the brush seal packages and their characteristics were tested in detail under pressure gradients up to 8 bar. The paper shows the results of different seal designs with regards to the blow-down characteristics during a live steam endurance test. Based on these results especially the axial design of the brush seal was found to be an important parameter, since it has a significant influence on potential vibration behaviour of the bristle pack under specific load conditions. In contrast, the transient live steam measurements have shown that a limited amount of movement and vibrations enables an improved radial adaptiveness, leading to reduced leakages during transient operations. Finally the paper introduces a new rotor concept for the steam test rig for further investigations of the brush seal - rotor interaction. It enables the utilization of new and especially varying rotor materials for increased steam parameters as well as the detection of the heat introduction into the rotor during the operating time by rotor-integrated temperature probes.

Use of a Lyophilized Reference Plasma to Compare Coagulation Test Procedures

1975 ◽  
Vol 34 (02) ◽  
pp. 426-444 ◽  
Author(s):  
J Kahan ◽  
I Nohén
Keyword(s):  
Oral Anticoagulant Therapy ◽  
Repeated Measurements ◽  
Test Procedures ◽  
Coagulation Activity ◽  
Close Relationship ◽  
Measured Activity ◽  
Test Materials ◽  
The Difference ◽  
The Stability ◽  
The One

SummaryIn 4 collaborative trials, involving a varying number of hospital laboratories in the Stockholm area, the coagulation activity of different test materials was estimated with the one-stage prothrombin tests routinely used in the laboratories, viz. Normotest, Simplastin-A and Thrombotest. The test materials included different batches of a lyophilized reference plasma, deep-frozen specimens of diluted and undiluted normal plasmas, and fresh and deep-frozen specimens from patients on long-term oral anticoagulant therapy.Although a close relationship was found between different methods, Simplastin-A gave consistently lower values than Normotest, the difference being proportional to the estimated activity. The discrepancy was of about the same magnitude on all the test materials, and was probably due to a divergence between the manufacturers’ procedures used to set “normal percentage activity”, as well as to a varying ratio of measured activity to plasma concentration. The extent of discrepancy may vary with the batch-to-batch variation of thromboplastin reagents.The close agreement between results obtained on different test materials suggests that the investigated reference plasma could be used to calibrate the examined thromboplastin reagents, and to compare the degree of hypocoagulability estimated by the examined PIVKA-insensitive thromboplastin reagents.The assigned coagulation activity of different batches of the reference plasma agreed closely with experimentally obtained values. The stability of supplied batches was satisfactory as judged from the reproducibility of repeated measurements. The variability of test procedures was approximately the same on different test materials.

Distributed Modeling Of Building Systems Through Cyber-Physical Integration

2019 ◽  
pp. 12-17
Keyword(s):  
Data Structure ◽  
Operating Conditions ◽  
Physical Models ◽  
Distributed Model ◽  
Physical Processes ◽  
Distributed Modeling ◽  
Distributed Models ◽  
Operating Modes ◽  
Building Systems ◽  
Important Practical Application

This article describes the proposed approaches to creating distributed models that can, with given accuracy under given restrictions, replace classical physical models for construction objects. The ability to implement the proposed approaches is a consequence of the cyber-physical integration of building systems. The principles of forming the data structure of designed objects and distributed models, which make it possible to uniquely identify the elements and increase the level of detail of such a model, are presented. The data structure diagram of distributed modeling includes, among other things, the level of formation and transmission of signals about physical processes inside cyber-physical building systems. An enlarged algorithm for creating the structure of the distributed model which describes the process of developing a data structure, formalizing requirements for the parameters of a design object and its operating modes (including normal operating conditions and extreme conditions, including natural disasters) and selecting objects for a complete group that provides distributed modeling is presented. The article formulates the main approaches to the implementation of an important practical application of the cyber-physical integration of building systems - the possibility of forming distributed physical models of designed construction objects and the directions of further research are outlined.

The Demand For Money in Pakistan: Reply (Notes and Comments)

1975 ◽  
Vol 14 (3) ◽  
pp. 370-375
Author(s):  
M. A. Akhtar
Keyword(s):  
Interest Rates ◽  
Money Demand ◽  
Strong Support ◽  
Physical Capital ◽  
Careful Examination ◽  
Demand For Money ◽  
Weak Support ◽  
Complementarity Hypothesis ◽  
The Difference ◽  
The One

I am grateful to Abe, Fry, Min, Vongvipanond, and Yu (hereafter re¬ferred to as AFMVY) [1] for obliging me to reconsider my article [2] on the demand for money in Pakistan. Upon careful examination, I find that the AFMVY results are, in parts, misleading and that, on the whole, they add very little to those provided in my study. Nevertheless, the present exercise as well as the one by AFMVY is useful in that it furnishes us with an opportunity to view some of the fundamental problems involved in an empi¬rical analysis of the demand for money function in Pakistan. Based on their elaborate critique, AFMVY reformulate the two hypo¬theses—the substitution hypothesis and the complementarity hypothesis— underlying my study and provide us with some alternative estimates of the demand for money in Pakistan. Briefly their results, like those in my study, indicate that income and interest rates are important in deter¬mining the demand for money. However, unlike my results, they also suggest that the price variable is a highly significant determinant of the money demand function. Furthermore, while I found only a weak support for the complementarity between money demand and physical capital, the results obtained by AFMVY appear to yield a strong support for that rela¬tionship.1 The difference in results is only a natural consequence of alter¬native specifications of the theory and, therefore, I propose to devote most of this reply to the criticisms raised by AFMVY and the resulting reformulation of the two mypotheses.

EFFECT OF OPERATING TIME OF THE WELLS IN THE STEADY DRAINAGE MODE BEFORE STOPPING ON THE RESULTS OF THE STUDY OF PRESSURE BUILD-UP CURVES

2017 ◽  
pp. 48-50
Author(s):  
E. F. Gilfanov
Keyword(s):  
Operating Time ◽  
Previous History ◽  
Operation Time ◽  
Pressure Recovery ◽  
Recovery Curve ◽  
History Of ◽  
Accuracy Of Results ◽  
Theoretical Pressure

Operation time of the well before stopping for investigating the pressure recovery curve in hydrodynamic studies is an important parameter affecting the quality and accuracy of results of research processing. Comparing the actual and theoretical pressure curves and the derivative, it’s possible to eliminate the uncertainty in the choice of previous history of the well operation.

Effect of leakage and blockage on the acoustic behavior of particle filters

2019 ◽  
Vol 67 (6) ◽  
pp. 483-492
Author(s):  
Seonghyeon Baek ◽  
Iljae Lee
Keyword(s):  
Transfer Matrix ◽  
Particle Filters ◽  
Acoustic Analysis ◽  
Transmission Loss ◽  
One Dimensional ◽  
Filter System ◽  
The Difference ◽  
The One ◽  
Analytical Approaches ◽  
Good Agreement

The effects of leakage and blockage on the acoustic performance of particle filters have been examined by using one-dimensional acoustic analysis and experimental methods. First, the transfer matrix of a filter system connected to inlet and outlet pipes with conical sections is measured using a two-load method. Then, the transfer matrix of a particle filter only is extracted from the experiments by applying inverse matrices of the conical sections. In the analytical approaches, the one-dimensional acoustic model for the leakage between the filter and the housing is developed. The predicted transmission loss shows a good agreement with the experimental results. Compared to the baseline, the leakage between the filter and housing increases transmission loss at a certain frequency and its harmonics. In addition, the transmission loss for the system with a partially blocked filter is measured. The blockage of the filter also increases the transmission loss at higher frequencies. For the simplicity of experiments to identify the leakage and blockage, the reflection coefficients at the inlet of the filter system have been measured using two different downstream conditions: open pipe and highly absorptive terminations. The experiments show that with highly absorptive terminations, it is easier to see the difference between the baseline and the defects.

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