This document discusses bulk oil and minimum oil circuit breakers. It defines circuit breakers and explains their need to protect electrical equipment from faults. It describes how bulk oil circuit breakers use oil as both an insulating and interrupting medium, while minimum oil circuit breakers only use a small amount of oil in the interrupting chamber. The document outlines the operation of both types of oil circuit breakers and compares their advantages and disadvantages. Maintenance of oil circuit breakers is also briefly discussed.
Air Blast & SF6 Circuit Breaker Design and Construction anuphowlader1
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.
How is power transformer protected??? This provides a basic understanding of power transformer. Furthermore, the protective relay application on power transformer is included.
Air Blast & SF6 Circuit Breaker Design and Construction anuphowlader1
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.
How is power transformer protected??? This provides a basic understanding of power transformer. Furthermore, the protective relay application on power transformer is included.
Basics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protection
This directional over current relay employs the principle of actuation of the relay....It has a metallic disc free to rotate between the poles of two...
Basics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protectionBasics of busbar protection
This directional over current relay employs the principle of actuation of the relay....It has a metallic disc free to rotate between the poles of two...
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
An electrical circuit breaker is a switching device which can be operated manually and automatically for controlling and protection of electrical power system respectively. As the modern power system deals with huge currents, the special attention should be given during designing of circuit breaker for safe interruption of arc produced during the operation of circuit breaker.
The modern power system deals with huge power network and huge numbers of associated electrical equipments. During short circuit fault or any other types of electrical fault these equipment as well as the power network suffer a high stress of fault current in them which may damage the equipment and networks permanently.
For saving these equipment and the power networks the fault current should be cleared from the system as quickly as possible. Again after the fault is cleared, the system must come to its normal working condition as soon as possible for supplying reliable quality power to the receiving ends. In addition to that for proper controlling of power system, different switching operations are required to be performed.
So for timely disconnecting and reconnecting different parts of power system network for protection and control, there must be some special type of switching devices which can be operated safely under huge current carrying condition. During interruption of huge current, there would be large arcing in between switching contacts, so care should be taken to quench these arcs in circuit breaker in safe manner. The circuit breaker is the special device which does all the required switching operations during current carrying condition.
Switchgear is a general term used to refer to a range of switches, circuit breakers, fuses, etc., which are used in an electric power system to control, regulate and switch the circuit on and off.
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, by interrupting continuity, to immediately discontinue electrical flow.
Introduction, Operation of 12-pulse converter as receiving and sending terminals of HVDC system, Equipment required for HVDC System and their significance, Comparison of AC and DC transmission, Control of HVDC transmission
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
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.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
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
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.
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/
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.
Immunizing Image Classifiers Against Localized Adversary Attacks
Bulk oil and min oil circuit breaker
1. Bulk Oil And Minimum Oil Circuit Breaker
Presented by
SAURABH DAYAL SINGH (130050109106)
YASH PATEL (130050109088)
Semester – VII
ELECTRICAL ENGINEERING DEPARTMENT
BABARIA INSITUTE OF TECHNOLOGY
VARNAMA
SWITCHGEAR AND PROTECTION
2. WHAT IS CIRCUIT BREAKER ?
NEED OF CIRCUIT BREAKER ?
WHERE IT IS USED ?
HOW IT OPERATES ?
3. WHAT IS A CIRCUIT BREAKER
A circuit breaker is an equipment that breaks a circuit either manually or
automatically under all conditions at no load, full load or short circuit.
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 by interrupting continuity, to
immediately discontinue electrical flow.
4. NEED OF CIRCUIT BREAKER
During short circuit fault or any other types of electrical fault these equipment as
well as the power network suffer a high stress of fault current in them which may
damage the equipment and networks permanently.
For saving these equipments and the power networks the fault current should be
cleared from the system as quickly as possible.
5. Two contacts called electrode remains
closed under normal operating
conditions.
When fault occurs on any part of the
system, the trip coil of the circuit
breaker get energized and contacts are
separated.
HOW IT OPERATES
6. ARC PHENOMENON
The arc provides the low resistance path to the current and the current in the
circuit remains uninterrupted.
When a short circuit occurs, the contacts of circuit breaker begin to separate
The p.d between the contacts is sufficient to ionize the air or oil or gas.
This ionized air acts as conductor and arc is struck between them even though
contacts of breaker are opened
7.
8. The arc resistance depends upon the following factors.
1. Degree of ionization
2. Length of the arc
3. Cross Section of the arc
9. METHODS OF ARC EXTINCTION
HIGH RESISTANCE METHOD
LOW RESISTANCE METHOD
10. High Resistance Method
The resistance of arc is increased by
1. Lengthening the arc
2. Cooling the arc
3. Reducing cross section of
arc
4. Splitting the arc
Low Resistance Method
1.Lengthening of the gap
2. High pressure
3.Cooling
4.Blast effect
If rate of heat generation is greater than rate of
heat dissipation between the contacts arc will be
extinguished.
If the dielectric strength increases more rapidly
than the restricking voltage arc is extinguished.
ARC INTERRUPTION METHOD
11. RATING, SELECTION OF BREAKERS
Rated voltage:12 KV to 765KV
Rated current: 200,400,630,800,1000,1250,1600,2000, 2500,3150,4000A
Rated frequency: 50 or 60Hz
Short circuit breaking current:12.5,16,20,25,31.5,40,50,63,80 KA
Rated short time withstand current: 1s
12. BREAKER COMPARISON
Functions performed Protections
Isolation Control
Switchgear Overloads Short-circuit
Fuse Yes Yes No No
Disconnector No No Yes No
Switch No No Yes Yes
Disconnector – fuse Yes Yes Yes No
Switch – fuse Yes Yes Yes Yes
Contactor No No No Yes
Circuit-breaker Yes Yes Yes Yes
13.
14.
15. SELECTION OF SWITCHING DEVICES
LOW VOLTAGE
FUSE
MCB
ELCB
MCCB
ISOLATOR
CONTACTOR
HIGH VOLTAGE
ACB
LOCB
VCB
SF6 BREAKER
HT FUSE
16. Mineral oil has better insulating property than air.
In oil circuit breaker the fixed contact and moving contact are immerged inside the
insulating oil.
Whenever there is a separation of current carrying contacts in the oil, the arc in
circuit breaker is initialized at the moment of separation of contacts.
Due to this arc the oil is vaporized and decomposed in mostly hydrogen gas and
ultimately creates a hydrogen bubble around the arc.
This highly compressed gas bubble around the arc prevents re-striking of the arc
after current reaches zero crossing of the cycle.
The oil circuit breaker is the one of the oldest type of circuit breakers.
OIL CIRCUIT BREAKER
17. TYPES OF OIL CIRCUIT BREAKERS
1. Bulk oil circuit breakers:
(a)Plain break oil circuit breakers
(b) Arc control oil circuit breakers
(b.1) Self-blast oil circuit breakers—in which arc control is provided by internal
means. The arc itself is employed for its own extinction efficiently.
We have to common types ----
(i) Plain explosion pot.
(ii) Cross jet explosion pot.
(iii) Self-compensated explosion pot.
(b.2) Forced-blast oil circuit breakers—in which arc control is provided by mechanical
means external to the circuit breaker.
2. Low Oil Circuit Breaker
18. Bulk oil circuit breaker or BOCB is such types of circuit breakers where oil is
used as arc quenching media as well as insulating media between current carrying
contacts and earthed parts of the breaker.
The oil used here is same as transformer insulating oil .
The circuit breaker which uses more oil or which is bulky is called bulk oil circuit
breaker.
The construction is simple and it consists of fixed and moving contacts enclosed in
a strong weather –tight earthed tank containing oil up to a certain level and an air
cushion above the oil level.
BULK OIL CIRCUIT BREAKER
20. 25 December 2017 20
1. Oil has high dielectric strength
2. Oil absorbs arc energy while
decomposing
3. Good cooling property of the gas
formed due to decomposition
4. It acts as an insulator between
the live parts and earth
DISADVANTAGES
1. Long arcing time
2. Do not permit high speed of
interruption
3. Arc interruption control can be
obtained only by increasing the
length of arc
ADVANTAGES
21. MINIMUM OIL CIRCUIT BREAKER
These types of circuit breakers utilize oil as the
interrupting media.
A minimum oil circuit breaker places the
interrupting unit in insulating chamber at live
potential. The insulating oil is available only in
interrupting chamber.
The features of designing MOCB is to reduce
requirement of oil, and hence these breaker are
called minimum oil circuit breaker.
22. When the contacts are separated in
oil arc is formed.
The heat of arc decomposes oil and
gases are formed.
These gases expand due to heating
of the arc.
The gas flowing near the contact
zone cause cooling and splitting of
the arc and the arc gets
extinguished.
OPERATION
23. 1. Requires less quantity of oil
2. Requires smaller space
3. Maintenance is less
4. Cost per breaking capacity in
MVA is less
5. Suitable for both manual and
automatic operation
1. Possibility of fire and explosion.
2. Difficult to remove gases from
the space between contacts.
3. Oil deteriorates rapidly due to
carbonization
4. Smaller quantity of oil, so
carbonization increases.
DISADVANTAGESADVANTAGES
24. MAINTANAINCE OF OIL CIRCUIT BREAKERS
During inspection of the breaker, the following points should be kept in view :
1. Check the current carrying parts and arcing contacts. If the burning is severe,
the contacts should be replaced.
2. Check the dielectric strength of the oil. If the oil is badly discolored, it should
be changed or reconditioned. The oil in good condition should withstand 30
kV for one minute in a standard oil testing cup with 4 mm gap between
electrodes.
3. Check the insulation for possible damage. Clean the surface and remove
carbon deposits with a strong and dry fabric.
4. Check the oil level.
25. CONCLUSION
• Therefore, we conclude that circuit breaker is the most essential part of the
electrical networks as it protects every device from damage. It helps us to
detect the fault and area affected by it.
• Nowadays vacuum and SF6 circuit breakers are widely used due to their
reliable and fast operations.