The document discusses different types of circuit breakers classified based on the medium used for arc extinction, including oil circuit breakers, which use insulating oil to extinguish arcs. Oil circuit breakers are further divided into plain break, self-blast, and forced-blast oil circuit breakers based on their arc control mechanisms. Low oil circuit breakers are also introduced, which use a minimal amount of oil separated into two compartments for insulation and arc extinction purposes.
It describes about the circuit breaker and components and types of high voltage circuit breaker. It also explains about the working principle of the circuit breaker.
Every power supply depends upon a reliable infeed of electricity. Air circuit breakers reliably protect electrical installations against damage or fire as a result of short circuits, ground faults, or overload faults.
A switchgear or electrical switchgear is a generic term which includes all the switching devices associated with mainly power system protection. It also includes all devices associated with control, metering and regulating of electrical power system. Assembly of such devices in a logical manner forms a switchgear. This is the very basic definition of switchgear.
⋗To get more with details
https://www.youtube.com/channel/UC2SvKI7eepP241VLoui1D5A
Unit I: Introduction to Protection System:
Introduction to protection system and its elements, functions of protective relaying, protective zones, primary and backup protection, desirable qualities of protective relaying, basic terminology.
Relays:
Electromagnetic, attracted and induction type relays, thermal relay, gas actuated relay, design considerations of electromagnetic relay.
Unit-II: Relay Application and Characteristics:
Amplitude and phase comparators, over current relays, directional relays, distance relays, differential relay.
Static Relays: Comparison with electromagnetic relay, classification and their description, over current relays, directional relay, distance relays, differential relay.
Unit-III Protection of Transmission Line:
Over current protection, distance protection, pilot wire protection, carrier current protection, protection of bus, auto re-closing,
Unit-IV: Circuit Breaking:
Properties of arc, arc extinction theories, re-striking voltage transient, current chopping, resistance switching, capacitive current interruption, short line interruption, circuit breaker ratings.
Testing Of Circuit Breaker: Classification, testing station and equipments, testing procedure, direct and indirect testing.
Unit-V Apparatus Protection:
Protection of Transformer, generator and motor.
Circuit Breaker: Operating modes, selection of circuit breakers, constructional features and operation of Bulk Oil, Minimum Oil, Air Blast, SF6, Vacuum and d. c. circuit breakers.
It describes about the circuit breaker and components and types of high voltage circuit breaker. It also explains about the working principle of the circuit breaker.
Every power supply depends upon a reliable infeed of electricity. Air circuit breakers reliably protect electrical installations against damage or fire as a result of short circuits, ground faults, or overload faults.
A switchgear or electrical switchgear is a generic term which includes all the switching devices associated with mainly power system protection. It also includes all devices associated with control, metering and regulating of electrical power system. Assembly of such devices in a logical manner forms a switchgear. This is the very basic definition of switchgear.
⋗To get more with details
https://www.youtube.com/channel/UC2SvKI7eepP241VLoui1D5A
Unit I: Introduction to Protection System:
Introduction to protection system and its elements, functions of protective relaying, protective zones, primary and backup protection, desirable qualities of protective relaying, basic terminology.
Relays:
Electromagnetic, attracted and induction type relays, thermal relay, gas actuated relay, design considerations of electromagnetic relay.
Unit-II: Relay Application and Characteristics:
Amplitude and phase comparators, over current relays, directional relays, distance relays, differential relay.
Static Relays: Comparison with electromagnetic relay, classification and their description, over current relays, directional relay, distance relays, differential relay.
Unit-III Protection of Transmission Line:
Over current protection, distance protection, pilot wire protection, carrier current protection, protection of bus, auto re-closing,
Unit-IV: Circuit Breaking:
Properties of arc, arc extinction theories, re-striking voltage transient, current chopping, resistance switching, capacitive current interruption, short line interruption, circuit breaker ratings.
Testing Of Circuit Breaker: Classification, testing station and equipments, testing procedure, direct and indirect testing.
Unit-V Apparatus Protection:
Protection of Transformer, generator and motor.
Circuit Breaker: Operating modes, selection of circuit breakers, constructional features and operation of Bulk Oil, Minimum Oil, Air Blast, SF6, Vacuum and d. c. circuit breakers.
Switchgear and protection lecture 2 type of circuit breakers and applicationsanuphowlader1
A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit. Its basic function is to detect a fault condition and interrupt current flow.
Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation. Circuit breakers are made in varying sizes, from small devices that protect an individual household appliance up to large switchgear designed to protect high voltage circuits feeding an entire city.
https://www.youtube.com/channel/UC2SvKI7eepP241VLoui1D5A
This is a presentation series part 3 on Frequently Asked Questions on Steam Turbines in large steam power plants. All questions are answered properly and any doubt may be mailed to the writer.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Circuit Breaker is one of the most important device in Power System.
This presentation gives general information about the working principle, types, advantages & Disadvantages, application of circuit breaker.
Air - Blast Circuit Breakers: Types, Advantages, Disadvantages, Applicationvikasverma433
Air - Blast circuit breakers employ high pressure Air – Blast as an arc quenching medium. The contacts are opened in a high flow of air blast established by the opening blast valve.
Fluxtrol's "Best Practice for Design and Manufacturing of Heat Treating Induc...Fluxtrol Inc.
With the use of good design practices, one can improve coil longevity and improve production quality. By eliminating failure points in the initial design, proper material selection, improved cooling and proper magnetic flux control, induction tooling life can be increased. Computer simulation has been proven to be an effective tool for predicting not only electromagnetic parameters of a designed system, but also heat patterns in a given part and in the induction coil itself. When a coil has magnetic flux controllers present, their influence may also be predicted by computer simulation. With an extensive library of published case studies in induction coil design and performance evaluations, we are confident with the use of these tools and proper coil geometries and implementation, production life and quality can be improved on most induction heat treating inductors. These design practices have been used by the authors for over 20 years with proven results. A case is examined of a CVJ stem hardening coil, in which the principles discussed can be applied to most other hardening coils.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
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.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
1. CIRCUITBREAKERS
CONTENT
Oil circuit Breakers
Low Oil circuit Breakers
High Oil circuit Breakers
Prepared By
Mr.K.Jawahar, M.E.,
Assistant Professor
Department of EEE
Circuit Breakers
Kongunadunadu College of Engineering and Technology Depar tment of EEE
2. Classification of Circuit Breakers
However, the most general way of classification is on the basis
of medium used for arc extinction.
The medium used for arc extinction is usually oil, air, sulphur
hexafluoride (SF6) or vacuum. Accordingly, circuit breakers
may be classified into :
(i) Oil circuit breakers which employ some insulating oil
(e.g., transformer oil) for arc extinction.
(ii) Air-blast circuit breakers in which high pressure air-blast
is used for extinguishing the arc.
(iii) Sulphur hexafluoride circuit breakers in which sulphur
hexafluoride (SF6) gas is used for arc extinction.
(iv) Vacuum circuit breakers in which vacuum is used for arc
extinction.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
3. Oil Circuit Breakers
• In such circuit breakers, some insulating oil (e.g., transformer oil)
is used as an arc quenching medium. The contacts are opened
under oil and an arc is struck between them.
• The heat of the arc evaporates the surrounding oil and dissociates
it into a substantial volume of gaseous hydrogen at high pressure.
The hydrogen gas occupies a volume about one thousand times
that of the oil decomposed.
• The oil is, therefore, pushed away from the arc and an expanding
hydrogen gas bubble surrounds the arc region and adjacent
portions of the contacts.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
4. • The arc extinction is facilitated mainly by two processes Firstly,
the hydrogen gas has high heat conductivity and cools the arc, thus
aiding the deionization of the medium between the contacts.
• Secondly, the gas sets up turbulence in the oil and forces it into the
space between contacts, thus eliminating the arcing products from
the arc path.
• The result is that arc is extinguished and circuit current
interrupted.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
5. Advantages.
(i) It absorbs the arc energy to decompose the oil into gases which
have excellent cooling properties.
(ii) It acts as an insulator and permits smaller clearance between live
conductors and earthed components.
(iii) The surrounding oil presents cooling surface in close proximity
to the arc.
Disadvantages.
(i) It is inflammable and there is a risk of a fire.
(ii) It may form an explosive mixture with air
(iii) The arcing products (e.g., carbon) remain in the oil and its
quality deteriorates with successive operations. This necessitates
periodic checking and replacement of oil.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
6. Types of Oil Circuit Breakers
(i) Bulk oil circuit breakers: which use a large quantity of oil.
Such circuit breakers may be classified into :
(a) Plain break oil circuit breakers (b) Arc control oil circuit
breakers.
(ii) Low oil circuit breakers: which use minimum amount of oil.
In such circuit breakers, oil is used only for arc extinction; the
current
conducting parts are insulated by air or porcelain or organic
insulating material.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
7. Plain Break Oil Circuit Breakers
• A plain-break oil circuit breaker involves the simple process of
separating the contacts under the whole of the oil in the tank.
• There is no special system for arc control other than the increase
in length caused by the separation of contacts.
• The arc extinction occurs when a certain critical gap between the
contacts is reached.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
8. • Under normal operating conditions, the fixed and moving
contacts remain closed and the breaker carries the normal circuit
current.
• When a fault occurs, the moving contacts are pulled down by
the protective system and an arc is struck which vaporizes the oil
mainly into hydrogen gas.
• The arc extinction is facilitated by the following processes :
(i) The hydrogen gas bubble generated around the arc cools the arc
column and aids the deionization of the medium between the
contacts.
(ii) The gas sets up turbulence in the oil and helps in eliminating the
arcing products from the arc path.
(iii) As the arc lengthens due to the separating contacts, the dielectric
strength of the medium is increased.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
9. Disadvantages
(i) There is no special control over the arc other than the increase in
length by separating the moving contacts. Therefore, for
successful interruption, long arc length is necessary.
(ii) These breakers have long and inconsistent arcing times.
(iii) These breakers do not permit high speed interruption.
• Due to these disadvantages, plain-break oil circuit breakers are
used only for low-voltage applications where high breaking-
capacities are not important. It is a usual practice to use such
breakers for low capacity installations for voltages not
exceeding 11 kV.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
10. Arc Control Oil Circuit Breakers
(i) Self-blast oil circuit breakers - in which arc control is provided
by internal means i.e. the arc itself is employed for its own
extinction efficiently.
(ii) Forced-blast oil circuit breakers - in which arc control is
provided by mechanical means external to the circuit breaker.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
11. (i) Self-blast oil circuit breakers.
In this type of circuit breaker, the gases produced during arcing
are confined to a small volume by the use of an insulating rigid
pressure chamber or pot surrounding the contacts.
Since the space available for the arc gases is restricted by the
chamber, a very high pressure is developed to force the oil and
gas through or around the arc to extinguish it.
The magnitude of pressure developed depends upon the value of
fault current to be interrupted. As the pressure is generated by the
arc itself, therefore, such breakers are sometimes called self-
generated pressure oil circuit breakers.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
12. Several designs of pressure chambers (sometimes called
explosion
pots) have been developed and a few of them are described
below
(a) Plain explosion pot
• It is a rigid cylinder of insulating material and encloses the fixed
and moving contacts. The moving contact is a cylindrical rod
passing through a restricted opening (called throat) at the bottom.
• When a fault occurs, the contacts get separated and an arc is
struck between them. The heat of the arc decomposes oil into a
gas at very high pressure in the pot. This high pressure forces the
oil and
gas through and round the arc to extinguish it.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
13. (b) Cross jet explosion pot
This type of pot is just a modification of plain explosion pot. It is
made of insulating material and has channels on one side which
act as arc splitters.
The arc splitters help in increasing the arc length, thus facilitating
arc extinction. When a fault occurs, the moving contact of the
circuit breaker begins to separate. As the moving contact is
withdrawn, the arc is initially struck in the top of the pot.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
14. (c) Self-compensated explosion pot
• This type of pot is essentially a combination of plain explosion
pot and cross jet explosion pot. Therefore, it can interrupt low as
well as heavy short circuit currents with reasonable accuracy.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
15. (ii) Forced-blast oil circuit breakers.
• In a forced -blast oil circuit breaker, oil pressure is created by the
piston-cylinder arrangement.
• The movement of the piston is mechanically coupled to the
moving contact. When a fault occurs, the contacts get separated
by the protective system and an arc is struck between the
contacts.
• The piston forces a jet of oil towards the contact gap to
extinguish the arc. It may be noted that necessary oil pressure
produced does not in any way depend upon the fault current to
be broken.
Advantages
(a) Since oil pressure developed is independent of the fault current
to be interrupted, the performance at low currents is more
consistent than with self-blast oil circuit breakers.
(b) The quantity of oil required is reduced considerably.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
16. Low Oil Circuit Breakers
Construction.
• There are two compartments separated from each other but both
filled with oil. The upper chamber is the circuit breaking
chamber while the lower one is the supporting chamber.
• The two chambers are separated by a partition and oil from one
chamber is prevented from mixing with the other chamber.
• This arrangement permits two advantages. Firstly, the circuit
breaking chamber requires a small volume of oil which is just
enough for arc extinction.
• Secondly, the amount of oil to be replaced is reduced as the oil
in the supporting chamber does not get contaminated by the arc.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
17. (i) Supporting chamber
• It is a porcelain chamber mounted on a metal chamber. It is filled
with oil which is physically separated from the oil in the circuit
breaking compartment.
• The oil inside the supporting chamber and the annular space
formed between the porcelain insulation and bakelised paper is
employed for insulation purposes only.
(ii) Circuit-breaking chamber
• It is a porcelain enclosure mounted on the top of the supporting
• compartment. It is filled with oil and has the following parts :
(a) upper and lower fixed contacts (b) moving contact
(c) Turbulator
(iii) Top chamber
• It is a metal chamber and is mounted on the circuit-breaking
chamber. It provides expansion space for the oil in the circuit
breaking compartment.Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
18. Operation.
Under normal operating conditions, the moving contact remains
engaged with the upper fixed contact.
When a fault occurs, the moving contact is pulled down by the
tripping springs and an arc is struck. The arc energy vaporizes the
oil and produces gases under high pressure.
This action constrains the oil to pass through a central hole in the
moving contact and results in forcing series of oil through the
respective passages of the turbulator.
The process of turbulation is orderly one, in which the sections of
the arc are successively quenched by the effect of separate
streams of oil moving across each section in turn and bearing
away its gases.
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers
20. Reference:
• V.K.MEHTA,ROHIT MEHTA, “Principles of Power System”,
S.Chand,2018.
• B.Rabindranath and N.Chander, ‘Power System Protection and
Switchgear’, New Age International (P) Ltd., First Edition
2011.
20
Kongunadunadu College of Engineering and Technology Depar tment of EEE
Circuit Breakers