L-9 MAGNETIC CIRCUITS

ELE 1001: Basic Electrical Technology Objectives To solve various kinds of problems involving parallel magnetic circuits. Dept. of E&E, MIT, Manipal

Content Parallel magnetic circuit ELE 1001: Basic Electrical Technology Content Parallel magnetic circuit Dept. of E&E, MIT, Manipal

Parallel magnetic circuit ELE 1001: Basic Electrical Technology Parallel magnetic circuit More than one path for flux. Total flux Φ is split into Φ1 and Φ2 such that Φ = Φ1+ Φ1 A B C D E F Φ Φ1 N Φ2 Analogous electrical circuit Dept. of E&E, MIT, Manipal

Parallel magnetic circuit with air gap ELE 1001: Basic Electrical Technology Parallel magnetic circuit with air gap Φ1 Φ2 A B C D E F Φ Analogous electrical circuit Dept. of E&E, MIT, Manipal

ELE 1001: Basic Electrical Technology Exercise1 The core shown has a relative permeability of 4000. Find the current required for the exciting coil to produce a flux of 10 milliWb in the central limb. Take total number of turns of the coil as 500 turns. Ans: 2.387 A Dept. of E&E, MIT, Manipal

ELE 1001: Basic Electrical Technology Exercise2 A magnetic circuit made of silicon steel is as shown. The central limb has a cross sectional area of 800 mm2 and a coil of 500 turns. Each of the side limbs has an area of 500 mm2. Calculate the magnetizing current required to produce a flux of 1 mWb in the 1 mm air gap if μr=1000, length BE = 150 mm; length BAGIDE = length BCHJFE = 250 mm. Neglect leakage factor. 1mm 5mm A B C D E F G H I J Ans: 2.04 A Dept. of E&E, MIT, Manipal

Summary More than one path for flux in parallel magnetic circuit. ELE 1001: Basic Electrical Technology Summary More than one path for flux in parallel magnetic circuit. Total flux divides into the available parallel paths. Dept. of E&E, MIT, Manipal