Switchgear and protection summary in an electric power system, switchgear is the combination of electrical disconnect switches, fuses or circuit breakers used to. R bhide, fundamentals of powersystem protectionphi. Distance protection is costly so far distribution network, electric utilities and on sub transmission lines over current protection. Fundamentals of power system protection by paithankar and s. Protective relays monitor the current andor voltage of the power system to detect problems with the power system. A typical application could involve generators, motors, transformers, feeder circuits. Medium voltage technical guide electrical engineering portal. How to download switchgear protection and power systems by. The construction of qbn7 switchgear is internal arc resistant in accordance with iec 62271200, pm type, a flr accessibility, for the protection of personnel and other equipment. Switchgear protection and power systems by sunil s rao. Distance relay protection the basic principle is that the apparent impedance seen by the relay reduces drastically in case of line fault.
Switchgear and protection we are all familiar with low voltage switches and rewirable fuses in our home. The protection index is the level of protection provided to by an. Switchgear also provides isolation of circuits from power supplies. Switchgear provides equipment protection for transformers, lines, cables, and capacitor banks used to energize and deenergize capacitor banks and other circuits switchgear includes. Power engineers must know the basics of switchgear. Switch gear and protection textbook are one of the famous textbook for engineering students. Switchgear and protection textbook free download by bakshi. This video provides all the important concept of switchgear and protection of power system in detail and also provides some important points to. Bakshi explained every information neatly without any mistake.
Medium voltage technical guide basics for mv design according to iec standards 2017 edition. The best distribution system is one that will, costeffectively and safely, supply adequate electric service to both present and future probable loadsthis section is intended to aid in selecting, designing and installing such a system. One of the basic functions of switchgear is protection, which is interruption of shortcircuit and overload fault currents while maintaining service to unaffected circuits. The ip code is a coding system to indicate protection index. Fundamentals of electrical substations and switchgear. Paithankar formerly professor and head electrical engineering department visvesvaraya national institute of technolorn nagpur s. During normal operation, switchgear permits to switch on or off generators, transmission lines, distributors and other electrical equipment. It also includes all devices associated with control, metering and regulating of electrical power systems. The basics of switching devices in medium voltage switchgear most electrical appliances used in household, commercial and industrial applications work with low voltage.
Agenda an overview mv network basic definitions circuit breaker switchgear control gear fault basic functions disconnection control protection. Low voltage switchgear provides centralized control and protection of low voltage power equipment and circuits in industrial, commercial and utility installations involving transformers, generators, motors and power feeder circuits. Fire, protection against, 230 firepumpmotor protection, 230 footing resistance, tower, 303 frequency, compensation of relays for changes in, 49 effect on induction relays, 32, 39 frequencyconverter protection, see generator protection fundamental principles of. Protection index protection of people against direct contact and protection of equipment against certain external influences is required by international standards. Thus switchgear can be taken as a general term covering a wide range of equipment concerned with the switching, protection, and control of various electrical equipment. Fire, protection against, 230 firepumpmotor protection, 230 footing resistance, tower, 303 frequency, compensation of relays for changes in, 49 effect on induction relays, 32, 39 frequencyconverter protection, see generator protection fundamental principles of protective relaying, 4 fuse, coordinating with a, 335. Voltage panel, switchboard and switchgear no matter where or how it is applied, you will soon realize that the circuit breaker. Learning the basics k001ac 40 high power medium voltage and low voltage switchgear k002ac 41. Sep 10, 2019 electrical power system by jb gupta is very useful for basics ideas of power system and best for competitive exams and all topics are covered. Several crucial terms are for better understanding of the presented material. The protection index is the level of protection provided to by an enclosure against access to hazardous parts, the penetration of solid foreign bodies and of water. Medium voltage products technical guide protection. Typical, they are used in industrial, commercial and electric utility installations. Contents relay buchholz relay circuit breakers instrument transformer 3.
The aim is to avoid or to limit the destructive or dangerous consequences of excessive shortcircuit currents, or those due to overloading and insulation failure, and to separate the defective circuit from the rest of the installation. Switchgear and protection notes pdf sgp notes pdf book starts with the. Assembly of such devices in a logical manner forms switchgear. Apr, 2019 we are a participant in the amazon services llc associates program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites. Top 100 switchgear and protection interview questions. Switchgear free download as powerpoint presentation.
Click here download free this book by j b gupta consists of more than 17000 multiple type questions this book has the contents below dc basics and networks and electromagnetic theory ac basics and networks dc machines ac machines. The neutral point of the generator is usually earthed, so as to facilitate the protection of the stator winding and associated system. The nec also covers minimum requirements for special occupan cies including hazardous locations and special use type facilities such as healthcare facilities, places of. Identify instrument transformers for protection applications.
By extension then, the definition could also include devices used to regulate, meter, and control your. Gis there are two terms presented in iec gas insulated switchgear and ieee gas insulated substations. Download analog electronic circuits by j b gupta pdf. Tata mcgrawhill education, apr 1, 2001 electric circuitbreakers 456 pages. It is the ability of the protection system to operate correctly. Power system protection and switchgear badri ram, d. The general layout of a protection system may be viewed as given in the following figure. Pdf ee6702 protection and switchgear ps books, lecture. High voltage is used not only to transmit electrical energy over very large distances, but also for regional distribution to the load centers via fine branches. Are those which are directly protected by a protective system such as relays, fuses or switchgears. Circuit breakers provide a manual means of energizing and deenergizing a circuit.
Paralleling switchgear psg is a combination of protection, metering, control and switching elements acting as an integrated system to control the distribution of power for the following systems. Ee2402 protection and switchgear l t p c 3 0 0 3 unit i introduction 9 importance of protective schemes for electrical apparatus and power system. If a fault occurring in a zone can be immediately detected and or isolated by a protection scheme dedicated to that particular zone. Introduction to switchgear and transformers ea technology. Switchgear circuit breaker mcb arcing vacuum switchgear isolator types of circuit breaker lightning arrestor. A switchgear is a general term used for an electrical apparatus intended for switching and interrupting the current in the power system under normal and abnormal operating conditions covering the combination of switching devices and a wide range of associated auxiliaries e.
The switch is used to manually open and close the electrical circuit in our home and electrical fuse is used to protect our household electrical circuit from over current and short circuit faults. Interview question of circuit breaker and switchgear. For those who dont know, electrical switchgear sometimes just called switchgear is a fairly broad, generic term that includes a variety of switching devices used to protect your power system from overloads. In other words systems used for switching, controlling and protecting the electrical power circuits and different types of electrical equipment are known as switchgear. Sep 17, 20 over current protection though simple and economical, require readjustment if change in circuit condition occurs. Sreekala, assistant lecture department of electrical and electronics engineering. Download switchgear protection and power systems by sunil s rao pdf.
Typically, switchgear in substations are located on both the high and lowvoltage sides of large power transformers. Switchgear is the essential element for power protection in power generating stations and grid stations. To provide a means of starting and stopping the motor and, at. To detect the fault and initiate the operation of the circuit breaker to isolate the defective element from. Summary switchgear and protection when the fault occurs the relay 2 connected to ct 8 and pt 7 actuates and close its contact 6 current flows from the battery 5 in the trip circuit 4 trip coil 3 is energized and cb 1 operating mechanism is actuated. Importance of protective schemes for electrical apparatus and power system. Switchgear and protection textbook free download switchgear and protection textbook by bakshi free download in pdf. Introduction to switchgear and transformers the knowledge required by nontechnical staff working in the power distribution and transmission industry has increased as the profile of productivity has been substantially raised, and safety has remained a major priority in all areas of work. Suited to applications where load is quite widely distributed throughout site. A switchgear is a generic term which includes all the switching devices associated with power system protection. Download pdf digital protection for power system by a. Impedance is inserted in the earthing lead to limit the magnitude of the earth fault current.
Medium voltage switchgear assemblies provide centralized control of and protection for medium voltage power equipment and circuits. Typical generator protection elements 15 synchronizer. A good electric power system should ensure the availability of electrical power. Understand protective relaying viewpoints and select applicable protection plans. Bhide assistant professor electrical engineering department visvesvaraya national institute of technology nagpur. I think this book is enough for engineering students who. Lecture notes on switchgear and protection devices for. Medium voltage switchgear assembly medium voltage switchgear assemblies provide centralized control of and protection for medium voltage power equipment and circuits. Relay is a sensing device which senses abnormal voltage and current conditions in power system and sends signal to circuit breaker to remove faulty part. By extension then, the definition could also include devices used to regulate, meter, and control your power system. Pdf electrical power system by jb gupta pdf download.
The basics of switching devices in medium voltage switchgear. Upon completing this electrical power system protection and switchgear training course successfully, participants will be able to. Here you can find analog electronic circuits by j b gupta free download shared files. The switchgear on the lowvoltage side of the transformers may be located in a building, with mediumvoltage circuit breakers for distribution circuits, along with metering, control, and protection equipment. This course is based on terms used in ieee and iec regulations. Switchgear is also used to enhance system availability by allowing more than one source to feed a load. Here you can find switchgear protection and power systems by sunil s rao a very nice book free download shared files. Only two phase and one earth fault relay is required for complete protection of three phase line. It applies to enclosure of electrical equipments with a rated voltage of less then or equal to 72. Some equipment is meant for switching and not sensing the fault.
Switchgear and protective devices 2015 8 p a g e risk of synchronous motors in large industrial premises falling out of step and tripping out. The function of a switchgear switchgear has to perform the functions of carrying, making and breaking the normal load current like a switch. Ee6702 protection and switchgear notes r20 velalar college of engineering and. Switchgear and protection electrical engineering mcq. Lowvoltage switchgear and controlgear literature library. Switchgear and protection notes sgp notes sgp pdf notes fundamentals of power system protection by paithankar and s. The present technical manual is intended as an aid in project design and the application of lowvoltage switchgear and controlgear in switchgear assemblies and machine control. The reliability feature has two basic elements, which are dependability and security. The information is intended to help readers understand the purpose of electrical distribution systems and associated equipment and increase their technical knowledge about it. Distribution automation handbook prototype elements of power d istribution systems 1mrs757959 4 3 elements of power distribution systems 3. Electrical power system by jb gupta is very useful for basics ideas of power system and best for competitive exams and all topics are covered. Switchgear and protection pdf notes sgp pdf notes smartzworld. Selection of the protection system and relays depends on and is correlated with the plant characteristics, type of industrial process and its service continuity.
The focus of the document is on electromechanical switchgear, however electronic. Mar 25, 2017 this video provides all the important concept of switchgear and protection of power system in detail and also provides some important points to remember for exams and interviews. Power system protection college of engineering and. Switchgear and protection the sequence of function during abnormal condition. If the ratio of apparent impedance to the positive sequence impedance is less than unity, it indicates a fault. An switchgear and protection by sunil s rao pdf overview of grounding system ungrounded on switchgear and protection by sunil s rao pdf photo.
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