DC circuits: Ohm’s law and Kirchhoff’s laws, analysis of series, parallel and series-parallel circuitsexcited by independent voltage sources. Power and energy, maximum power transfer theorem appliedto the series circuit and its applications. Single-phase circuits: Generation of sinusoidal voltage, frequency of generated voltage, average value, RMS value, form, and peak factors. Voltage and current relationship, with phasor diagrams, in R, L, and C circuits.
Single-phase circuits (continued): Analysis of R-L, R-C, R-L-C Series and Parallel circuits, Real power, reactive power, apparent power, and Power factor. Measurement of power. Three-phase circuits: Generation of three-phase power, representation of balanced star (3 wire and 4 wire system) and delta connected loads, the relation between phase and line values of voltage and current from phasor diagrams, advantages of three-phase systems. Measurement ofthree-phase powerby two-wattmeter method.
DC Machines: (a) Principle of operation, constructional details, induced emf expression, types of generators, and the relation between induced emf and terminal voltage. (b) Principle of operation, back emf and torque equations, types of motors, characteristics (shunt andseries only), and applications. Transformers: Necessity of transformer, the principle of operation, Types, and construction of single-phase transformers, emf equation, losses, variation of losses with respect to load, efficiency, and condition for maximum efficiency.
Three-phase induction Motors: Concept of rotating magnetic field, Principle of operation, constructional features of motor, types – squirrel cage and wound rotor, slip and problems on the slip, significance of slip, applications. Three-phase synchronous generators: Principle of operation, constructional details of salient and non-salient pole generators, synchronous speed, frequency of generated voltage, emf equation, with the concept of winding factor (excluding the derivation and calculation of winding factors).
Power transmission and distribution: Concept of power transmission and power distribution. Lowvoltage distribution system (400 V and 230 V) for domestic, commercial, and small-scale industry through block diagrams only. Electricity bill: Power rating of household appliances including air conditioners, PCs, laptops, printers,etc. Definition of “unit” used for consumption of electrical energy, two-part electricity tariff, calculation of electricity bill for domestic consumers. Equipment Safety measures: Working principle of Fuse and Miniature circuit breaker (MCB), merits and demerits. Personal safety measures: Electric Shock, Earthing and its types, Safety Precautions to avoid shock,and Residual Current Circuit Breaker (RCCB)