21EE51 Transmission and Distribution syllabus for EE

Introduction to Power System: Structure of electric power system:

generation, transmission and distribution. Advantages of higher voltage transmission: HVAC, EHVAC, UHVAC and HVDC. Interconnection. Feeders, distributors and service mains.

Overhead Transmission Lines:

A brief introduction to types of supporting structures and line conductorsConventional conductors; Aluminium Conductor steel reinforced (ACSR), All – aluminium alloy conductor (AAAC) and All –aluminium conductor (AAC). High temperature conductors; Thermal resistant aluminium alloy (ATI),Super thermal resistant aluminium alloy (ZTAI), Gap type thermal resistant aluminium alloy conductor steel reinforced (GTACSR), Gap type super thermal resistant aluminium alloy conductor steel reinforced (GZTACSR). Bundle conductor and its advantages. Importance of sag, Sag calculation – supports at same and different levels, effect of wind and ice. Line vibration and vibration dampers. Overhead line protection against lightening; ground wires.

Overhead Line Insulators:

A brief introduction to types of insulators, material used- porcelain, toughened glass and polymer (composite). Potential distribution over a string of suspension insulators. String efficiency, Methods of increasing string efficiency. Arcing horns.

Line Parameters:

Introduction to line parameters- resistance, inductance and capacitance. Calculation of inductance of single phase and three phase lines with equilateral spacing, unsymmetrical spacing, double circuit and transposed lines. Inductance of composite – conductors, geometric mean radius (GMR) and geometric mean distance (GMD). Advantages of single circuit and double circuit lines.). Calculation of capacitance of single phase and three phase lines with equilateral spacing, unsymmetrical spacing, double circuit and transposed lines. Capacitance of composite – conductor, geometric mean radius (GMR) and geometric mean distance (GMD). Advantages of single circuit and double circuit lines.

Performance of Transmission Lines:

Classification of lines – short, medium and long. Current and voltage relations, line regulation and Ferranti effect in short length lines, medium length lines considering Nominal T and nominal circuits, and long lines considering hyperbolic form equations. Equivalent circuit of a long line. ABCD constants in all cases.

Corona:

Phenomena, disruptive and visual critical voltages, corona loss. Advantages and disadvantages of corona. Methods of reducing corona.

Underground Cable:

Types of cables, constructional features, insulation resistance, thermal rating, charging current, grading of cables – capacitance and inter-sheath. Dielectric loss. Comparison between ac and DC cables. Limitations of cables. Specification of power cables.

Distribution:

Primary AC distribution systems – Radial feeders, parallel feeders, loop feeders and interconnected network system. Secondary AC distribution systems – Three phase 4 wire system and single phase 2 wire distribution, AC distributors with concentrated loads. Effect of disconnection of neutral in a 3 phase four wire system.

Reliability and Quality of Distribution System:

Introduction, definition of reliability, failure, probability concepts, limitation of distribution systems, power quality, Reliability aids.

Course outcome (Course Skill Set)

At the end of the course the student will be able to :

(1)Explain transmission and distribution scheme, identify the importance of different transmission systems and types of insulators.

(2)Analyze and compute the parameters of the transmission line for different configurations.

(3)Assess the performance of overhead lines.

(4)Interpret corona, explain the use of underground cables.

(5)Classify different types of distribution systems; examine its quality & reliability.

Assessment Details (both CIE and SEE)

• The weightage of Continuous Internal Evaluation (CIE) is 50% and for Semester End Exam (SEE) is 50%.
• The minimum passing mark for the CIE is 40% of the maximum marks (20 marks out of 50).
• A student shall be deemed to have satisfied the academic requirements and earned the credits allotted to each subject/ course if the student secures not less than 35% ( 18 Marks out of 50)in the semester-end examination(SEE), and a minimum of 40% (40 marks out of 100) in the sum total of the CIE (Continuous Internal Evaluation) and SEE (Semester End Examination) taken together

Continuous Internal Evaluation:

Three Unit Tests each of 20 Marks (duration 01 hour)

• First test at the end of 5th week of the semester
• Second test at the end of the 10th week of the semester
• Third test at the end of the 15th week of the semester

Two assignments each of 10 Marks

• First assignment at the end of 4th week of the semester
• Second assignment at the end of 9th week of the semester Group discussion/Seminar/quiz any one of three suitably planned to attain the COs and POs for 20 Marks (duration 01 hours)
• At the end of the 13th week of the semester
• The sum of three tests, two assignments, and quiz/seminar/group discussion will be out of 100 marks and will be scaled down to 50 marks (to have less stressed CIE, the portion of the syllabus should not be common /repeated for any of the methods of the CIE. Each method of CIE should have a different syllabus portion of the course).

CIE methods /question paper is designed to attain the different levels of Bloom’s taxonomy as per the outcome defined for the course.

Semester End Examination:

Theory SEE will be conducted by University as per the scheduled timetable, with common question papers for the subject (duration 03 hours)

• The question paper will have ten questions. Each question is set for 20 marks.
• There will be 2 questions from each module. Each of the two questions under a module (with a maximum of 3 sub-questions), should have a mix of topics under that module.

The students have to answer 5 full questions, selecting one full question from each module.

Suggested Learning Resources:

Textbooks

1. A Course in Electrical Power, Soni Gupta and Bhatnaghar, DhanpatRai.

2. Principles of Power System, V.K. Mehta, Rohit Mehta S. Chand 1st Edition 2013.

Reference Books

1. Power System Analysis and Design, J. Duncan Gloverat el, Cengage Learning, 4th Edition 2008.

2. Electrical power Generation, Transmission Distribution, S.N. Singh PHI, 2nd Edition, 2009.

3. Electrical Power S.L.Uppal Khanna Publication.

4. Electrical power systems, C. L. Wadhwa, New Age, 5th Edition.

5. Electrical power systems, AshfaqHussain, CBS Publication.

6. Electric Power Distribution, A.S. Pabla, McGraw-Hill, 6th Edition,2012.

Note: For High temperature conductors refer www.jpowers.co.jp/english/product/pdf/gap_c1.pdf and Power.