AC circuit HAFONHA EAHKAJYTOCAABHJS 100 MARODHA BANKA JUGOSLAVIE 100
AC circuit
Agenda Today 1.Self-Inductance and Multi Inductance 2.Energy stored in Magnetic Field 3.RL Circuit 4.AC Circuit
Agenda Today 1. Self-Inductance and Multi Inductance 2. Energy stored in Magnetic Field 3. RL Circuit 4. AC Circuit
Self-inductance(自感系数) L=Ψ/I Unit:H According to Faraday's Law: Ψ d(LI) dI 8L= dt dt dt
Self-inductance(自感系数) L / I Unit: H According to Faraday’s Law: dt dI L dt d LI dt d L ( )
Self-inductance of ideal solenoid Cross section area A length:1 current I number of turns:N permeability:u B=μ1
Self-inductance of ideal solenoid l Cross section area : A length: l current : I number of turns: N permeability: I l N B
N2 Ψ=NBS= IS 半专4S=Wherenis画 per unit length Multi induction(互感) Emf caused by the change in current carried by another loop
IS l N NBS 2 S n V l N I L 2 2 Where n is turns per unit length Multi induction（互感） Emf caused by the change in current carried by another loop
Multi inductance(互感系数) 平，=N,Φ21=M2 Y2=NΦ12=M122 M12=M21=M 821=-M dt 612=-M dt
Multi inductance（互感系数）1 2 I1 I2 12 21 21 2 21 21 1 N M I 12 1 12 12 2 N M I M12 M21 M dt dI M dt dI M 2 12 1 21
互感概念演示仪
Tesla coil
Tesla coil
Example:Inside the magnetic material with permeability u is a straight long wire and rectangular loop as the figure shows.find the multi inductance solution B= 2πr dΦ=BdS =41 ldr dr 2元r a+b Φ L= n 2元r 2元 a Φ M= =w1 a+b 2π a
Example: Inside the magnetic material with permeability is a straight long wire and rectangular loop as the figure shows.find the multi inductance solution r dr a b l I r I B o 2 ldr r I d BdS o 2 a Il a b dr r a b Il a o o ln 2 2 a l a b I M o ln 2