This document discusses providing security against faulty synchronization when connecting two electrical sources. It defines proper closure as having acceptable phase angle difference, slip frequency, voltage difference and magnitude. Faulty synchronization can cause damage through excessive mechanical stress and current flows. Modern automatic synchronizing relays calculate a safe advance time to close based on measured phase angle and slip frequency. Sync check relays supervise synchronization but may introduce delays. Proper synchronization is important for generator connection and tie line applications.
�The sample calculations shown here illustrate steps involved in calculating the relay settings for generator protection.
�Other methodologies and techniques may be applied to calculate relay settings based on specific applications.
The protections of generator are the most complex and elaborate due to the following reasons: Generator is a large machine, connected to bus-bars. It is accompanied by unit transformers, auxiliary transformers and a bus system. ... The protection of generator should be co-ordinate with associated equipment's.
Tutorial on Distance and Over Current ProtectionSARAVANAN A
Contents
• Protection Philosophy of ERPC
• Computation of Distance Relay Setting
• System Study to Understand Distance Relay
Behaviour
• DOC and DEF for EHV system
�The sample calculations shown here illustrate steps involved in calculating the relay settings for generator protection.
�Other methodologies and techniques may be applied to calculate relay settings based on specific applications.
The protections of generator are the most complex and elaborate due to the following reasons: Generator is a large machine, connected to bus-bars. It is accompanied by unit transformers, auxiliary transformers and a bus system. ... The protection of generator should be co-ordinate with associated equipment's.
Tutorial on Distance and Over Current ProtectionSARAVANAN A
Contents
• Protection Philosophy of ERPC
• Computation of Distance Relay Setting
• System Study to Understand Distance Relay
Behaviour
• DOC and DEF for EHV system
Infinite bus bar is one which keeps constant voltage and frequency although the load varies. Thus it may behave like a voltage source with zero internal impedance and infinite rotational inertia.
Excitation System & capability curve of synchronous generatorMANOJ KUMAR MAHARANA
Excitation systems perform control and protective functions essential to the satisfactory performance of the power system.
The amount of continuous reactive power a generator can supply is restricted by various limits. In the over-excitation region limits are imposed by rotor heating or amount of field current and second is the stator current. In the under excitation region the limits are imposed by load angle. So in steady state the generator should always operate within this region and the loci of the various limiters are called the capability curve of the generator.
Transformer vector group_test_conditionsSARAVANAN A
Test Conditions for various vector groups commonly under use are listed along with pictorial representation. Assuming the reader has sufficient exposure to transformer winding connections.
Transformer Vector Group Test conditions
YNd1, YNd11, Dyn11, YNyn0and more
On Load Tap Changer (OLTC) is used in "High Power Transformers" to control output voltage, when electric load on transformers get increase the output voltage get decrease due to internal voltage drop inside winding, change in tap is required to maintain output voltage. OLTC is a device which perform tap changing in High Power Transformers during On Load conditions and is powered by a motor.
Practical handbook-for-relay-protection-engineersSARAVANAN A
The ‘Hand Book’ covers the Code of Practice in Protection Circuitry including standard lead and device numbers, mode of connections at terminal strips, colour codes in multicore cables, Dos and Donts in execution. Also, principles of various protective relays and schemes including special protection schemes like differential,
restricted, directional and distance relays are explained with sketches. The norms of protection of generators, transformers, lines & Capacitor Banks are also given.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Infinite bus bar is one which keeps constant voltage and frequency although the load varies. Thus it may behave like a voltage source with zero internal impedance and infinite rotational inertia.
Excitation System & capability curve of synchronous generatorMANOJ KUMAR MAHARANA
Excitation systems perform control and protective functions essential to the satisfactory performance of the power system.
The amount of continuous reactive power a generator can supply is restricted by various limits. In the over-excitation region limits are imposed by rotor heating or amount of field current and second is the stator current. In the under excitation region the limits are imposed by load angle. So in steady state the generator should always operate within this region and the loci of the various limiters are called the capability curve of the generator.
Transformer vector group_test_conditionsSARAVANAN A
Test Conditions for various vector groups commonly under use are listed along with pictorial representation. Assuming the reader has sufficient exposure to transformer winding connections.
Transformer Vector Group Test conditions
YNd1, YNd11, Dyn11, YNyn0and more
On Load Tap Changer (OLTC) is used in "High Power Transformers" to control output voltage, when electric load on transformers get increase the output voltage get decrease due to internal voltage drop inside winding, change in tap is required to maintain output voltage. OLTC is a device which perform tap changing in High Power Transformers during On Load conditions and is powered by a motor.
Practical handbook-for-relay-protection-engineersSARAVANAN A
The ‘Hand Book’ covers the Code of Practice in Protection Circuitry including standard lead and device numbers, mode of connections at terminal strips, colour codes in multicore cables, Dos and Donts in execution. Also, principles of various protective relays and schemes including special protection schemes like differential,
restricted, directional and distance relays are explained with sketches. The norms of protection of generators, transformers, lines & Capacitor Banks are also given.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Comparison of Multi-Machine Transient Stability Limit Using UPFCIJMTST Journal
The stability of an interconnected power system is compare to normal or stable operation after having been
subjected to some form of disturbance. With interconnected systems continually growing in size and extending
over vast geographical regions, it is becoming increasingly more difficult to maintain synchronism between
various parts of the power system. This paper investigates the comparison of transient stabil ity limit of a
multi-machine power system wi th the help of a UPFC operated in perpendicular vol tage control
mo d e an d t h e i r i t ’ s c omp ar i s o n .
A Review on Power System Voltage Stability and Optimization TechniquesIJERA Editor
Power system voltage stability is a one of the major focused areas in recent days due to mismatch between generation and demand. Maintenance of voltage stability is a challenging issue in planning and security assessment of power systems. Voltage stability is the ability of a power system to maintain steady acceptable voltages at all buses in the power system under normal operating conditions and after being subjected to a disturbance. Long-term voltage instability problems can occur in heavily loaded systems where the electrical distance is large between the generator and the load. Timely application of reactive power compensation or load shedding may prevent this type of voltage instability. System reactive power handling capacity can be improved with Flexible AC Transmission System (FACTS) devices. Identification of critical system locations to undertake appropriate remedial measures in operation is the concern. This paper reviews the performance of various types FACTS controllers in power system voltage stability problem and focuses on different optimization methods implemented for optimal placement and sizing of FACTS devices to minimize power losses.
Comparison of Shunt Facts Devices for the Improvement of Transient Stability ...IJSRD
This paper presents, the performance of STATCOM placed at midpoint of the two machine power system and compared with the performance of SVC. The comparison of various results found for the different type of faults (single line, double line & three phase fault) occur in long transmission line, and their removal by using shunt FACTS devices is analysed. Computer simulation results under a severe disturbance condition (three phase fault) for different fault clearing times, and different line lengths are analyzed. Both controllers are implemented using MATLAB/SIMULINK. Simulation results shows that the STATCOM with conventional PI controller installed with two machine three bus systems provides better damping oscillation characteristics in rotor angle as compared to two machine power system installed with SVC. The transient stability of two machine system installed with STATCOM has been improved considerably and post settling time of the system after facing disturbance is also improved.
Comparison of Shunt Facts Devices for the Improvement of Transient Stability ...IJSRD
This paper presents, the performance of STATCOM placed at midpoint of the two machine power system and compared with the performance of SVC. The comparison of various results found for the different type of faults (single line, double line & three phase fault) occur in long transmission line, and their removal by using shunt FACTS devices is analysed. Computer simulation results under a severe disturbance condition (three phase fault) for different fault clearing times, and different line lengths are analyzed. Both controllers are implemented using MATLAB/SIMULINK. Simulation results shows that the STATCOM with conventional PI controller installed with two machine three bus systems provides better damping oscillation characteristics in rotor angle as compared to two machine power system installed with SVC. The transient stability of two machine system installed with STATCOM has been improved considerably and post settling time of the system after facing disturbance is also improved.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Analysis of Voltage Sag on Power Distribution Networks with Different Transfo...paperpublications3
Abstract: In present era, power engineers need to plan the power system design in such a way that the system can sustain its Power Quality (PQ) even after facing all the above said problems. Along with that the system should also be compatible with the increasing demand of power supply. Quality of power depends on the system design, reliability and efficiency so study of PQD is important. PQD affects industrial as well as large commercial customers. Voltage sag is also referred as voltage dip. Voltage dip is the term given by IEC while the term "voltage sag" (VS) is used by North American power quality commission. VS creates disturbance in the pure sinusoidal waveform of voltage which in turn deteriorates the power quality of the system. VS occur for very short duration of 0.5 to 30 cycles. It is decrease in RMS voltage of about 90 % to 10 % of nominal voltage. Although VS occurs for very short duration but its effects deteriorates system with time decreases life period of the system. The present work is an attempt to analyse the voltage sag on power distribution network with different transformer connections. The field specifications obtained are used in MATLAB/SIMULINK and the results are discussed.
Basics of Power systems
Network topology
Transmission and Distribution
Load and Resource Balance
Economic Dispatch
Steady State System Analysis
Power flow analysis
Dynamic System Analysis
Transient stability
Small Signal Modeling Of Controller For Statcom Used In Distribution System F...IJERA Editor
In this paper non-linear model of the STATCOM is linearized and the following strategies have been adopted .
Hence, a small signal model is adopted here. Here, the grid voltage lags the fundamental component of the
STATCOM converter terminal voltage with a phase angle difference
' '
. Small signal modeling of the phase
angle
' '
and modulation index
' m '
is also done. A single PI-controller for the reactive component current of
the STATCOM has been designed. In this model, the DC-link capacitor voltage is held constant without using a
separate controller. The STATCOM are designed using SVPWM technique. Through adjustment of the
modulation index, fast modulation of the STATCOM reactive power output can be achieved due to high
sensitivity of the same with respect to the output voltage of the STATCOM VSC. The model, with PI controllers
has been simulated in MATLAB/SIMULINK environment with variation of the pre-charge voltage on the DClink
capacitor with linear loads (inductive). Improvement of the power factor of the grid current is achieved for
linear loads.
POWER QUALITY IMPROVEMENT AND FAULT RIDE THROUGH OF GRID CONNECTED WIND ENE...Bharadwaj S
This work tries to improve the power quality by compensating reactive power with Active Power Filters and also to analyze Fault Ride Through of Grid connected wind energy conversion systems.
Impact of hybrid FACTS devices on the stability of the Kenyan power system IJECEIAES
Flexible alternating current transmission system (FACTS) devices are deployed for improving power system’s stability either singly or as a combination. This research investigates hybrid FACTS devices and studies their impact on voltage, small-signal and transient stability simultaneously under various system disturbances. The simulations were done using five FACTS devices-static var compensator (SVC), static synchronous compensator (STATCOM), static synchronous series compensators (SSSC), thyristor controlled series compensator (TCSC) and unified power flow controller (UPFC) in MATLAB’s power system analysis toolbox (PSAT). These five devices were grouped into ten pairs and tested on Kenya’s transmission network under specific contingencies: the loss of a major generating machine and/or transmission line. The UPFC-STATCOM pair performed the best in all the three aspects under study. The settling times were 3 seconds and 3.05 seconds respectively for voltage and rotor angle improvement on the loss of a major generator at normal operation. The same pair gave settling times of 2.11 seconds and 3.12 seconds for voltage and rotor angle stability improvement respectively on the loss of a major transmission line at 140% system loading. From the study, two novel techniques were developed: A performance-based ranking system and classification for FACTS devices.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
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1. Providing Security Against
Faulty Synchronization and
Attendant Damage
Providing Security Against
Faulty Synchronization and
Attendant Damage
25
SynchronizingSynchronizing
2. Synchronizing
As protection practitioners, we spend the majority
of our time designing protection systems to trip
Designing a protection system to close requires
careful attention to security
You want to provide security against improper
closure of two electrical sources
What defines proper closure?
Introduction
Synchronizing
3. Synchronizing
Protect against harmful effects of closing two ac
electrical sources with excessive:
- Phase Angle Difference (Ø)
- Slip Frequency (ΔF or S)
- High or Low Voltage (UVL, LVL)
- Voltage Difference (ΔV)
Synchronizing is Used in Generator Synchronizing
and System Line Restoration Applications
Synchronizing
Introduction
10. Synchronizing
Effects of Synchronizing Errors
Excessive Phase Angle – Machine Issues
Excessive Phase Angle - Closing at a static angle as low as
15 degrees can cause as large a power swing as closing at 0
degrees with an excessive slip frequency of 0.5 Hz (2-second
scope).
Tends to sharply “bump” the generator
Mechanical shock can cause extensive damage to the rotor
Though mechanical damage may not be significant
cumulative fatigue damage on the shaft will ultimately reduce
the life expectancy of the generator
This cumulative fatigue damage on the shaft is often
expressed as a loss-of-life value.
High stator currents cause deformation of generator-end-
turns and eventual winding failure
Faulty synchronizing subjects the windings of the power
transformer to stress
Synchronizing
11. Synchronizing
Effects of Synchronizing Errors
Excessive Phase Angle – System Issues
Causes Instantaneous Power and VAr
Flows
May cause transient high voltage
May cause stability issue
Synchronizing
VA
VA
VB VB
VC
VC
ZB
ZA
ZC
12. Synchronizing
90O 180O0O
1 PU
Even a small angle (12 degrees) can cause
large instantaneous power flows
P= E1 * E2 (sin0)
Z
Even a small angle (12 degrees) can cause
large instantaneous power flows
Phase Angle Difference: Power Flows
A 12 degree close hard-loads a machine to 30% of full-load shock !
13. Synchronizing
Excessive Frequency Difference
Known as “hard loading”
Causes power flows
- Power out if slip is positive
- Power in if slip is negative
Cumulative mechanical stress on rotating machinery
Excessive frequency difference errors can cause a
disturbance when the power swing exceeds stability
limits
Synchronizing
14. Synchronizing
Excessive Voltage Difference
If the generator voltage is higher than the system
voltage, the generator will supply Vars
May cause transient high voltage
If the generator voltage is lower than the system
voltage, the generator will sink Vars
May trigger system instability as excitation
systems react and cause power oscillations
Synchronizing
15. Synchronizing
The Cost of Faulty Synchronization
Machine repair costs
Down Time
Lost Revenue
Lost of Interest on Investment
Synchronizing
18. SynchronizingSynchronizing
[1] Robert W. Beckwith, "Calculations of Circuit Breaker Closing Criteria for
Synchronizing a Generator." Beckwith Electric Company, August 1979.
[2] I. M. Canay, H. J. Rohrer, K. E. Schnirel, "Effect of Electrical Disturbances,
Grid Recovery Voltage and Generator Inertia on Maximization of Mechanical
Torques in Large Turbogenerator Sets." IEEE Transactions on Power
Apparatus and Systems, Vol. PAS-99, No.4, July/August 1980, pp. 1357-1370.
[3] H. H. Chen, G. E. Jablonka, J. V. Mitsche, J.B. Lewis, "Turbine-Generator
Loss-of-Life Analysis Following a Faulty Synchronization Incident." American
Power Conference, Chicago, Illinois, April 21-23, 1980.
[4] R. D. Dunlop, A. C. Parikn, "Verification of Synchronous Machine Modeling
in Stability Studies: Comparative Tests of Digital and physical Scale Model
Power System Simulations. IEEE Transactions on Power Apparatus and
Systems, Vol. PAS -98, No.2, March/April 1979, pp. 369-378.
[5] D. R. Green, et al, "IEEE Screening Guide for Planned Steady-State
Switching Operations to Minimize Harmful Effects on Steam Turbine-
Generators." IEEE Transactions on Power Apparatus and Systems, Vol. PAS-
99, No.4, July/August 1980, pp. 1519-1521.
References
19. SynchronizingSynchronizing
[6] T. J. Hammons, "Stressing of Large Turbine-Generators at Shaft Couplings
and LP Turbine Final-Stage Blade Roots Following Clearance of Grid System
Faults and Faulty Synchronization." IEEE Transactions on Power Apparatus and
Systems, Vol. PAS -99, No.4, July/ August 1980, pp. 1652-1662.
[7] M. C. Jackson, S. D. Umans, "Turbine-Generator Shaft Torques and Fatigue:
Part III -Refinements to Fatigue Model and Test Results IEEE Transactions on
Power Apparatus and Systems, Vol. PAS-99, No.3, May/ June 1980, pp. 1259-
1268.
[8] John S. Joyce, Dietrich Lambrecht, "Status of Evaluating the Fatigue of
Large Steam Turbine-Generators Caused by Electrical Disturbances." IEEE
Transactions on Power Apparatus and Systems, Vol. PAS-99, No. 1, Jan./Feb.
1980, pp. 111-119.
[9] John S. Joyce, Tadeusz Kulig, Dietrich Lambrecht, “The Impact of High-
Speed Reclosure of Single and Multi- Phase System Faults on Turbine-
Generator Shaft Torsional Fatigue”. IEEE Transactions on Power Apparatus
and Systems, Vol. PAS- 99, No. 1, Jan./Feb. 1980, pp. 279-291.
[10] J. V. Mitsche, P. A. Rusche, “Shaft Torsional Stress Due to Asynchronous
Faulty Synchronization.” IEEE Transactions on Power Apparatus and Systems,
Vol. PAS-99, No.5, Sept./act. 1980, pp. 1864-1870.
References
20. SynchronizingSynchronizing
[11] D. G. Ramey, G. C. Kung, “Important Parameters in Considering
Transient Torques on Turbine-Generator Shaft Systems.” IEEE Transactions
on Power Apparatus and Systems, Vol. PAS-99, No. 1, Jan./Feb. 1980, pp.
311-317.
[12] P. A. Rusche, P. C. Krause, W. C. Hollopeter, “Results of an Investigation
into the Torsional Shaft Failure of a 21 MW Combustion Turbine.” IEEE
Publication No. CH1523-4/80/1172.
[13] Jan Stein, Horst Fick, “The Torsional Stress Analyzer for Continuously
Monitoring Turbine-Generators.” IEEE Transactions on Power Apparatus and
Systems, Vol.. PAS-99, No.2, March/April 1980, pp. 703-710.
[14] United States Department of the Interior, Bureau of Reclamation, Denver,
Colorado, “Power O and M Bulletin.” No.27, June 1957.
References
21. Synchronizing
Sync Check (25SC, 25SC+)
Automatic Synchronizer (25A)
Speed (Frequency) Matching (15)
Voltage Matching (90)
Synchronizing
Synchronizing Elements
22. Synchronizing
√−−−−−−GEN VOLTAGE RAISE/LOWER
√−−−−−−GEN SPEED RAISE/LOWER
−−−−√√DEAD LINE/BUS CLOSE
−−√√√VOLTAGE DIFFERENCE (ΔV) LIMIT
−−√√√LOWER VOLTAGE LIMIT (LVL)
−−√√√UPPER VOLTAGE LIMIT (UVL)
−−√−−BREAKER CLOSING TIME (TBC)
−−√√−−
FREQUENCY DIFFERENCE (ΔF)
LIMIT
−−−−√√PHASE ANGLE TIME DELAY (TSC)
−−AUTO√√PHASE ANGLE (Φ) LIMIT
15/9025A25SC+25SCDEVICE NUMBER
GEN
CONTROL
AUTO
SYNC
SYNC
CHECK
PLUS
SYNC
CHECKDEVICE
Synchronizing Elements
24. Synchronizing
Classic sync check relays use phase angle/time
- This is done so an inferred slip limit can be realized
Modern sync check relays use phase angle/slip
- Using slip frequency directly is better than using
time
- Do not have to widen the angle setting
- Do not have to have a deliberate delay
Affords faster restoration on tie line applications
Affords tighter angle settings for generator
applications
Sync Check Plus
27. Synchronizing
Generation
- Used to supervise an operator or automatic
synchronizing relay
Tie Line
- Used to verify static phase angle or extremely
low slip between systems
- Used to supervise a SCADA or automatic
synchronizing relay
Synchronizing
Sync Check Plus Applications
28. Synchronizing
Used to connect two electrical systems that are
separated
Have the ability to calculate an advance time to
close a breaker that takes into account the slip
frequency between the two systems
Φ = 360 S T
Applications
- Connect a generator to the grid
- Tie systems when one is islanded
Synchronizing
Automatic Synchronizing Relays
33. Synchronizing
Electromechanical Sync Check
in Series with Operator
**** WARNING ****
Close Characteristic
- Time Delay Cannot Be Adjusted to Zero
- Phase Angle Setting Varies with Applied Voltage
Blocking Characteristic
- Once Made Up, Opens at Large Angles Exiting
Zero Degrees ! ! !
35. Synchronizing
Electromechanical Sync Check
in Series with Operator
Synchronism-Check Relay Test
General Electric Type IJS52
The purpose of this test was to determine the blocking characteristics of the IJS Relay
set for 20° and minimum time delay. Tests were run for the following conditions:
With the initial phase angle at 0° and both inputs at 60Hz, increase the line frequency
to create a slip frequency (ΔF) and measure the blocking time and blocking angle.
TEST DATA
47. Synchronizing
Ring Bus
1 2
4 3
G Line
Line
Line
1 2
4 3
G Line
Line
Line
1 2
4 3
G Line
Line
Line
(a) Circuit breakers 1 and
4 are open; generator is
ready for sync.
(b) Circuit breaker 1
closes on rotating
phase angle. The
autosync closes the
breaker.
(c) Circuit breaker 4
is closed on the
static angle. The
sync check relay
closes the breaker.
NOTE: All lines are energized and tied.
Closed Breaker
Open Breaker
54. Synchronizing
Generation
- Speed matching is required to bring a generator’s
frequency equal to the grid frequency
- Voltage matching is required to bring a generator’s
voltage equal to the grid voltage
Speed & Voltage Matching Relays
55. Synchronizing
Supervise and control generation coming onto bus
(system)
- Control generator so ideal synchronizing conditions
occur
Speed match
Voltage match
- Properly close the breaker
Application: Generation
56. Synchronizing
Difficulties are often encountered that affect
operators and speed matching relays
- High inertia of turbine-generator causes response lags
- Governor control systems take time to physically
move, causing a response lag
The speed matching algorithm has to take the lags
into account or control overshoot will result
Speed Matching
62. Synchronizing
Supervise connection of two electrical systems
- Synchronous Tie: Systems are connected together at
some other location
- Asynchronous Tie: Systems are not connected anywhere
This is sometimes referred to as connected islanded
systems together
Application: System Restoration
66. Synchronizing
Provisions to Jump
Sync Check Angle
Under Certain System
Conditions
Auto Sync: Max ΔF Limit
Sync Check: Angle Limit, Low ΔF Limit
System Restoration Synchronizing DC
Control
