ELECTRICAL DEPARTMENT NOTICE BOARD

MID-SEMESTER TEST ,  SYLLABUS Design of A C Machines(7Th Semester- Electrical)

[ subject code : 2170909] (1)DESIGN OF THREE PHASE INDUCTION MOTOR: MAIN DIMENSIONS: Output equation, choice of specific loadings, separation of D and L. STATOR DESIGN: Stator winding design, Calculation of no. of turns per phase, Conductor’s area, Shape of the stator slots, Area of stator slots, Stator teeth design, Depth of the stator core, Length of air gap, Numerical problems related to above topics. ROTOR DESIGN: A. Squirrel cage rotor – Selection of no. of rotor slots, Effect of harmonics and choice of rotor slots to minimize harmonics, vibration, noise and voltage ripples, Rules for selecting no. of rotor slots, Methods for reducing harmonic torque, Design of rotor bars and rotor slots. Design of end rings and rotor core. B. Wound rotor - Calculation of number of rotor slots, Number of turns, Cross sectional area of rotor conductors, Types of rotor windings, Check for rotor tooth density, Design of rotor slot and rotor core. (2)DESIGN OF SINGLE PHASE INDUCTION MOTOR: Design of main dimensions, Design of stator, Design of rotor, Design of auxiliary winding. PERFORMANCE PARAMETERS EVALUATION: Rotor resistance, Stator resistance, Iron loss, Friction and Windage loss, Starting torque, Circle diagram, Calculation of capacitance for maximum torque. (3)DESIGN OF SYNCHRONOUS MACHINE: Output equation and design of main dimensions, Short Circuit Ratio (SCR) and its significance, Length of air gap and shape of pole face. ARMATURE DESIGN: Armature winding (Single layer and double layer), Number of armature slots, Slot dimensions, Length of mean turn, Calculation of armature resistance and reactance. DESIGN OF FIELD SYSTEM: Design of magnetic circuit, Open circuit characteristic, Determination of full load field MMF, Design of field winding, Determination of direct and quadrature axis synchronous reactance, Short circuit characteristics.