Electrical MATLAB

M-File Programming for Transmission Line: clc clear disp( 'STUDYING THE CHARECTERISTICS OF A TRANSMISSION LINE' ) disp( '***************************************************' ) disp( ' ' ) V=input( 'Receiving end line voltage in volt =' ); L=input( 'length of transmission line in km =' ); Pr=input( 'Rated power at receiving end load =' ); pf=input( 'power factor=' ); I=Pr/(sqrt(3)*V*pf); a1=acos(pf); Vr=V/sqrt(3) Ir=I*cos(a1)-j*I*sin(a1) r=input( 'resistance/km/phase=' ); x=input( 'inductive reactance/km/phase=' ); R=r*L; X=j*x*L; Z=R+X if V>20000 y=input( 'capacitive susceptance/km/phase=' ); Y=j*y*L m=Y*Z; end if V<20000 disp( 'SHORT TRANSMISSON LINE' ) disp( '**********************' ) A=1 B=Z C=0 D=A end if V>20000 & V<1

clc clear a=input ( 'A=' ); b=input ( 'B=' ); c=input ( 'C=' ); if a>b if a>b disp ( 'A is greater' ) elseif a||c disp ( 'A=C and greater than B' ) else disp ( 'C is greater' ) end elseif b>c if a||b disp ( 'A=B and greater than C' ) else disp ( 'B is greater' ) end elseif b||c disp ( 'B=C and greater than A' ) else disp ( 'C is greater' ) end (try it)

clc clear disp( 'Marks Calculation in Examination' ) disp( '********************************' ) disp( '50% Marks Before Mid Term Examination' ) disp( '-----------------------------------' ) m=input( 'Mid Term in 30% Marks=' ); if m<=30 & m>=0 disp( 'Right Input' ) else disp( 'Wrong Input!!!' ) end ct1=input( 'Class Test 1 in 10% Marks=' ); if ct1<=10 & ct1>=0 disp( 'Right Input' ) else disp( 'Wrong Input!!!' ) end ct2=input( 'Class Test 2 in 10% Marks=' ); if ct2<=10 & ct2>=0 disp( 'Right Input' ) else disp( 'Wrong Input!!!' ) end if ct1>ct2 ctm=ct1 else ctm=ct2 end a1=input( 'Assignment 1 in 5% Marks=' ); if a1<=5 & a1>=0 disp( 'Right Input' ) else disp( 'Wrong Input!!!' ) end DM=input( 'Attendance Before Mid[in 10 Days]=&

First, let's create a simple vector with 9 elements called a . a = [1 2 3 4 6 4 3 4 5] a = 1 2 3 4 6 4 3 4 5 Now let's add 2 to each element of our vector, a , and store the result in a new vector. Notice how MATLAB requires no special handling of vector or matrix math. b = a + 2 b = 3 4 5 6 8 6 5 6 7 Creating graphs in MATLAB is as easy as one command. Let's plot the result of our vector addition with grid lines. plot(b) grid on MATLAB can make other graph types as well, with axis labels. bar(b) xlabel( 'Sample #' ) ylabel( 'Pounds' ) MATLAB can use symbols in plots as well. Here is an example using stars to mark the points. MATLAB offers a variety of other symbols and line types. plot(b, '*' ) axis([0 10 0 10]) One area in which MATLAB excels is matrix computation. Creating a matrix is as easy as making a vector, using semicolons (;) to separate the rows of a matrix. A = [1 2

M-File Programming For Finding Per-Unit Impedance: -clc -clear -disp('CHANGING THE BASE OF PER-UNIT QUANTITIES') -x=input('given base MVA='); -y=input('given base KV='); -z=input('given per unit impedence='); -a=input('new base MVA='); -b=input('new base KV='); -disp('new per unit impedence='); -pu=z*(y/b)^2*(a/x) (Try it) M-File Programming For Finding Per-Unit Impedance: -clc -clear -disp('PERCENTAGE TRANSMISSION EFFICIENCY OF TX-LINE') -x=input('Receiving end voltage='); -y=input('Load current per-phase='); -z=input('Receiving end power factor='); -a=input('Sending end current='); -b=input('Resistance per-phase='); -disp('Percentage voltage transmission efficiency='); -PVTE=(((x*y*z)/((x*y*z)+(a^2*b)))*100 (try it)

M-File Programming For Subplotting: clc clear subplot(2,2,1) x=0:pi/1800:2*pi; y=sin(x); plot(x,y); title( 'Plot of sin(x)' ); grid subplot(2,2,2) x=0:pi/1800:2*pi; y=sin(x-2*pi/3) plot(x,y); title( 'Plot of sin(x-120)' ); grid subplot(2,2,3) x=0:pi/1800:2*pi; y=sin(x+2*pi/3) plot(x,y); title( 'Plot of sin(x-240)' ); grid (try it) M-File Programming For Three-Phase Voltage: clc clear t=0:pi/1800:2*pi; v1=100*cos(t); plot(t,v1); grid hold on v2=100*cos(t-2*pi/3); plot(t,v2); v3=100*cos(t+2*pi/3); plot (t,v3); title( 'Plotting Three-Phase Voltage of v1(t), v2(t) and v3(t)' ) xlabel ( 'Time in seconds' ) ylabel ( 'Voltage in volts' ) text (6,6, 'v1(t)' ) text (3,4, 'v2(t)' ) text (1,1, 'v3(t)' ) (try it) Discussion: · Plotting figure is also called graphing figure in MATLAB. · In this programming, we can easily