Introduction.pptx
- 1. Electrical Technology (EEA 1001) Indian Institute of Technology Bhubaneswar
- 2. Course Instructor Mark Distribution Dr. S Mohapatro Office # 216 Tel: 0674-7135744 M: 9337149010 IIT Bhubaneswar Email: sankarsan@iitbbs.ac.in Dr. C Perumalla Theory Components: 100 Marks Teacher Assessment: 20 Marks, Mid-Term: 30 Marks, Term End: 50 Marks Teacher Assessment (1): 10 Marks (Attendance, Assignment, One Class Test) Teacher Assessment (2): 10 Marks by Dr. C. Perumalla
- 3. Introduction: Sources of energy; General structure of electrical power systems, Power transmission and distribution via overhead lines and underground cables, Steam, Hydel, and Nuclear power generation. 1 Hr DC Networks: Kirchoff’s laws, node voltage and mesh current methods, Delta-star and star-delta conversion, Superposition principle, Thevenin’s and Norton’s theorems. 6 Hr Single phase AC Circuits: Single phase EMF generation, average and effective values of sinusoids, solution of R,L,C series circuits, the j operator, complex representation of impedances, phasor diagram, power factor, power in complex notation, solution of parallel and series – parallel circuits. 5 Hr Three phase AC Circuits: Three phase EMF generation, delta and Y – connections, line and phase quantities, solution of three phase circuits, balanced supply voltage and balanced load, phasor diagram, measurement of power in three phase circuits, Three phase four wire circuits. 3 Hr DC Transients: Study of DC Transients in R-L, R-C and R-L-C Circuits. 3 Hr Syllabus
- 4. Magnetic Circuits: Ampere’s circuital law, B – H curve, solution of magnetic circuits, hysteresis and eddy current losses, relays, an application of magnetic force, basic principles of stepper motor. Transformers: Construction, EMF equation, ratings, phasor diagram on no load and full load, equivalent circuit, regulation and efficiency calculations, open and short circuit tests, auto-transformers. DC Machines: Construction, EMF and Torque equations, Characteristics of DC generators and motors, speed control of DC motors and DC motor starters. Induction Motor: The revolving magnetic field, principle of orientation, ratings, equivalent circuit, Torque-speed characteristics, starters for cage and wound rotor type induction motors. Electrical Measuring Instruments: DC PMMC instruments, shunt and multipliers, multimeters, Moving iron ammeters and voltmeters, dynamometer, wattmeter, AC watt-hour meter, extension of instrument ranges.
- 5. Text Books: 1. Electrical Engg Fundamentals by Del Toro 2. Electric Circuits by J W Nilsson 3. Basic Electrical Engineering by Nagrath and Kothari 4. Basic Electrical Engineering by D C Kulshreshtha 5. Electrical and Electronic Technology by Huges 6. Electrical Technology by B L Thereja
- 6. Electrical Technology (EEA 1001) Indian Institute of Technology Bhubaneswar Generation, Transmission and Distribution
- 7. Introduction Lighting, heating, cooling and other domestic electrical appliances used in home. Street lighting, flood lighting of sporting arena, office building lighting, powering PCs etc. Irrigating vast agricultural lands using pumps and operating cold storages for various agricultural products. Running motors, furnaces of various kinds, in industries. Running locomotives (electric trains) of railways.
- 8. Basic Idea of Generation Prior to the discovery of Faraday’s Laws of electromagnetic discussion, electrical power was available from batteries with limited voltage and current levels. Although complicated in construction, D.C generators were developed first to generate power in bulk. However, due to limitation of the D.C machine to generate voltage beyond few hundred volts . Thus generation, transmission and distribution of d.c power were restricted to area of few kilometer radius with no interconnections between generating plants. In later half of eighties, in nineteenth century, it was proposed to have a power system with 3-phase, 50 Hz A.C generation, transmission and distribution networks.
- 9. A.C Generator A.C power can be generated as a single phase or as a balanced poly- phase system. It was found that 3-phase power generation at 50 Hz will be economical and most suitable. Present day three phase generators, used to generate 3-phase power are called alternators (synchronous generators).
- 10. Frequency, Voltage & Interconnected System The frequency of the generated emf for a p polar generator is given by (PN/2) Frequency of the generated voltage is standardized to 50 HZ in our country and several European countries. In USA and Canada it is 60 Hz. In absence of commutators, present day generated voltage in alternator is much higher, typically around 10 kV to 15 kV. It can be shown that rms voltage induced in a coil is proportional to φ and n i.e., Ecoil ∝ φ n where φ is the flux per pole and n is speed of the alternator.
- 11. Thermal, Hydel & Nuclear power stations Thermal plant
- 12. Hydel plants
- 13. Nuclear plants
- 14. General Structure of Power System
- 15. Transmission of Power The huge amount of power generated in a power station (hundreds of MW) is to be transported over a long distance (hundreds of kilometers) to load centers to cater power to consumers with the help of transmission line and transmission towers.
- 16. Distribution of Power Power receive at a 33 kV substation is first stepped down to 6 kV and with the help of under ground cables (called feeder lines), power flow is directed to different directions of the city. At the last level, step down transformers are used to step down the voltage form 6 kV to 400 V.
- 18. Conclusion Generation, transmission and distribution of electric power in our country is carried out as 3-phase system at 50 Hz. Three most important conventional methods of power generation in out country are: coal based thermal plants, Hydel plants and nuclear plants. Load centers (where the power will be actually consumed) are in general situated far away from the generating station. So to transmit the large amount of power (hundreds of MW) efficiently and economically over long distance, high transmission voltage (such as 400 kV, 220 kV) is used. Material used for transmission lines is bare is bare copper conductors which are supported at regular intervals by steel towers. Stack of disk type ceramic insulators are used between the HV line and the steel tower. Level of current decides the section of the line conductor and the level of voltage decides the amount of insulation required.