From 7f60ea012dd2524dae921a2a35adbf7ef21f2bb6 Mon Sep 17 00:00:00 2001 From: prashantsinalkar Date: Tue, 10 Oct 2017 12:27:19 +0530 Subject: initial commit / add all books --- 1445/CH6/EX6.1/ch6_ex_1.sce | 59 +++++++++++++++++++++++++++++++++++++++++++++ 1445/CH6/EX6.2/ch6_ex_2.sce | 50 ++++++++++++++++++++++++++++++++++++++ 1445/CH6/EX6.3/ch6_ex_3.sce | 49 +++++++++++++++++++++++++++++++++++++ 1445/CH6/EX6.4/ch6_ex_4.sce | 41 +++++++++++++++++++++++++++++++ 1445/CH6/EX6.5/ch6_ex_5.sce | 43 +++++++++++++++++++++++++++++++++ 5 files changed, 242 insertions(+) create mode 100644 1445/CH6/EX6.1/ch6_ex_1.sce create mode 100644 1445/CH6/EX6.2/ch6_ex_2.sce create mode 100644 1445/CH6/EX6.3/ch6_ex_3.sce create mode 100644 1445/CH6/EX6.4/ch6_ex_4.sce create mode 100644 1445/CH6/EX6.5/ch6_ex_5.sce (limited to '1445/CH6') diff --git a/1445/CH6/EX6.1/ch6_ex_1.sce b/1445/CH6/EX6.1/ch6_ex_1.sce new file mode 100644 index 000000000..758205da9 --- /dev/null +++ b/1445/CH6/EX6.1/ch6_ex_1.sce @@ -0,0 +1,59 @@ +//CHAPTER 6- MAGNETIC CIRCUITS +//Example 1 + +disp("CHAPTER 6"); +disp("EXAMPLE 1"); + +//VARIABLE INITIALIZATION +lA=17/100; //length of part A in m +l=3/100; //in m +lg=2/1000; //length of air-gap in m +N=1000; //number of turns +AB=10/100; //in m +BC=20/100; //in m +CD=10/100; //in m +I=1; //exciting current in Amperes +murA=1000; //relative permeability of part A +murB=1200; //relative permeability of part B +mu0=4*%pi*10^(-7); //absolute permeability in Henry/m + +//SOLUTION + +//solution (i) +ar=l*l; +rA=lA/(mu0*murA*ar); +disp(sprintf("(i) Reluctance of part A is %E AT/Wb",rA)); + +lB=(AB-(l/2))+(BC-l)+(CD-(l/2)); +rB=lB/(mu0*murB*ar); +disp(sprintf("Reluctance of part B is %E AT/Wb",rB)); + +//solution (ii) +lg=2*lg; +murg=1; +rg=lg/(mu0*murg*ar); +disp(sprintf("(ii) Reluctance of the two air gaps is %E AT/Wb",rg)); + +//solution (iii) +rT=rA+rB+rg; +disp(sprintf("(iii) Total reluctance is %E AT/Wb",rT)); + +//solution (iv) +mmf=N*I; +disp(sprintf("(iv) MMF is %d AT",mmf)); + +//solution (v) +totFlux=mmf/rT; +disp(sprintf("(v) Total flux is %E Wb",totFlux)); + + +//solution (vi) +b=totFlux/ar; +disp(sprintf("(vi) Flux density is %f Wb/m^2",b)); + +//Answers of (v) and (vi) do not match due to calculation mistake in the book + +//END + + + diff --git a/1445/CH6/EX6.2/ch6_ex_2.sce b/1445/CH6/EX6.2/ch6_ex_2.sce new file mode 100644 index 000000000..5c6bd3b41 --- /dev/null +++ b/1445/CH6/EX6.2/ch6_ex_2.sce @@ -0,0 +1,50 @@ +//CHAPTER 6- MAGNETIC CIRCUITS +//Example 2 + +disp("CHAPTER 6"); +disp("EXAMPLE 2"); + +//VARIABLE INITIALIZATION +dr=25/100; //diameter of steel ring in m +ds=3/100; //diameter of circular section in m +lg=1.5/1000; //length of air-gap in m +N=700; //number of turns +mu0=4*%pi*10^(-7); //absolute permeability in Henry/m +I=2; //in Amperes + +//SOLUTION + +//solution (i) +mmf=N*I; +disp(sprintf("(i) MMF is %d AT", mmf)); + +//solution (ii) +netMMF=(mmf-(0.35*mmf)); //mmf taken by iron path is 35% of total mmf +b=(mu0*netMMF)/lg; //phi=b*area, r=lg/(mu0*area) & mmf=phi*r => mmf=(b*lg)/mu0 => b=(mmf*mu0)/lg +disp(sprintf("(ii) The flux density of the air gap is %E Wb/m^2", b)); + +//solution (iii) +ar=%pi*((ds/2)^2); //area of cross-section of circular section +phi=ar*b; +disp(sprintf("(iii) The magnetic flux is %E Wb",phi)); + +//solution (iv) +rt=mmf/phi; +disp(sprintf("(iv) The total reluctance is %E AT/wb",rt)); + +//solution (v) +rg=lg/(mu0*ar); //reluctance of air gap +rs=rt-rg; //reluctance of steel +lr=%pi*dr; //circumference of ring +mur=lr/(mu0*rs*ar); +disp(sprintf("(v) The relative permeability of the steel ring is %E",mur)); + +//solution (vi) +disp(sprintf("(vi) Reluctance of steel is %E AT/Wb",rs)); + +//END + + + + + diff --git a/1445/CH6/EX6.3/ch6_ex_3.sce b/1445/CH6/EX6.3/ch6_ex_3.sce new file mode 100644 index 000000000..f17dfaefc --- /dev/null +++ b/1445/CH6/EX6.3/ch6_ex_3.sce @@ -0,0 +1,49 @@ +//CHAPTER 6- MAGNETIC CIRCUITS +//Example 3 + +disp("CHAPTER 6"); +disp("EXAMPLE 3"); + +//VARIABLE INITIALIZATION +lg1=0.025/100; //length of 1st air-gap in m +a1=(1*1)/10000; //in m^2 +lg2=0.02/100; //length of 2nd air-gap in m +a2=(1*1)/10000; //in m^2 +lg3=0.02/100; //length of 3rd air-gap in m +a3=(2*1)/10000; //in m^2 +phi=0.75/1000; //in Wb +lc1=0.5; //length through outer limb in m +lc2=0.5; //length through outer limb in m +lc3=0.2; //length through central limb in m +mu0=4*%pi*10^(-7); //absolute permeability in Henry/m + +//SOLUTUION + +//solution (a): when mur=infinity i.e., no mmf drops in any member of the core +rg1=lg1/(mu0*a1); //reluctance of 1st air-gap +rg2=lg2/(mu0*a2); //reluctance of 2nd air-gap +rg3=lg3/(mu0*a3); //reluctance of 3rd air-gap +rgeq=(rg1*rg2)/(rg1+rg2); //rgeq=rg2||rg3 +mmf1=phi*(rgeq+rg3); +mmf1=round(mmf1); //to round off the value +disp(sprintf("(a) MMF of the exciting coil when permeability is infinity is %d AT",mmf1)); + +//solution (b): when mur=5000 i.e., reluctance of magnetic core must be considered +mur=5000; +rc1=lc1/(mu0*mur*a1); //reluctance of first path in the core +rc2=lc2/(mu0*mur*a2); //reluctance of second path in the core +rc3=lc3/(mu0*mur*a3); //reluctance of third path in the core +r1=rg1+rc1; +r2=rg2+rc2; +r3=rg3+rc3; +req=(r1*r2)/(r1+r2); +totr=req+r3; +mmf2=phi*totr; +mmf2=round(mmf2); +disp(sprintf("(b) MMF of the exciting coil when permeability is 5000 is %d AT",mmf2)); + +//END + + + + diff --git a/1445/CH6/EX6.4/ch6_ex_4.sce b/1445/CH6/EX6.4/ch6_ex_4.sce new file mode 100644 index 000000000..957c97a28 --- /dev/null +++ b/1445/CH6/EX6.4/ch6_ex_4.sce @@ -0,0 +1,41 @@ +//CHAPTER 6- MAGNETIC CIRCUITS +//Example 4 + +disp("CHAPTER 6"); +disp("EXAMPLE 4"); + +//VARIABLE INITIALIZATION +di=10; //diameter of iron ring in cm +dr=1.5; //diameter of iron rod in cm +mui=900; //relative permeability of rod +mu0=4*%pi*10^(-7); //absolute permeability in Henry/m +lg=5/10; //length of air-gap in cm +N=400; //number of turns +I=3.4; //current through the winding in Amperes + +//SOLUTION +li=(di*%pi)-lg; //length of iron path +area=((dr^2)*%pi)/4; //area of iron cross-section + +//solution (a) +mmf=(4*%pi*N*I)/10; //in gilberts, since 1 AT=(4*pi)/10 +mmf=round(mmf); //to round off the value +disp(sprintf("(a) MMF is %d Gilberts",mmf)); + +//solution (b) +//tot reluctance = iron reluctance + air gap reluctance(mur=1 for air) +totR=(li/(area*mu0*mui))+(lg/(area*mu0*1)); +disp(sprintf("(b) The total reluctance is %E Gilberts/Maxwell",totR)); + +//solution (c) +phi=mmf/totR; +disp(sprintf("(c) The flux in the circuit is %f Maxwell",phi)); + +//solution (d) +b=phi/area; +disp(sprintf("(d) The flux density in the circuit is %f Gauss",b)); + +//Answers of (b), (c) & (d) are different because absolute permeability is not included in (b) + +//END + diff --git a/1445/CH6/EX6.5/ch6_ex_5.sce b/1445/CH6/EX6.5/ch6_ex_5.sce new file mode 100644 index 000000000..f1c1e5afc --- /dev/null +++ b/1445/CH6/EX6.5/ch6_ex_5.sce @@ -0,0 +1,43 @@ +//CHAPTER 6- MAGNETIC CIRCUITS +//Example 5 + +disp("CHAPTER 6"); +disp("EXAMPLE 5"); + +//VARIABLE INITIALIZATION +li=100/100; //length of iron part in m +ls=200/100; //length of steel part in m +lg=1/100; //length of air gap in m +ai=20/10000; //cross-sectional area of iron in m^2 +as=10/10000; //cross-sectional area of steel in m^2 +ag=20/10000; //cross-sectional area of air-gap in m^2 +muRi=300; //relative permeability of iron +muRs=900; //relative permeability of steel +muRg=1; //relative permeability of air +N=170; //number of turns +phi=9000*10^(-8); //flux in Wb (1 line = 10^(-8) Wb) +lkg=1.2; //leakage coefficient +mu0=4*%pi*10^(-7); //absolute permeability in Henry/m + +//SOLUTION +rg=lg/(mu0*muRg*ag); +mg=rg*phi; +mg=round(mg); //to round off the value +disp(sprintf("MMF of the air gap is %d AT",mg)); + +ri=li/(mu0*muRi*ai); +mi=lkg*ri*phi; +mi=round(mi); +disp(sprintf("MMF of iron is %d AT",mi)); + +rs=ls/(mu0*muRs*as); +ms=lkg*rs*phi; +ms=round(ms); +disp(sprintf("MMF of cast steel is %d AT",ms)); + +totMMF=mg+mi+ms; +I=totMMF/N; +disp(sprintf("Current through the coil is %f A",I)); + +//END + -- cgit