شبیه سازی اینورتر در متلب — به همراه کد

1% A Program For Analysis of a Voltage-source inverter with Sinusoidal-Pulse-Width Modulated output.
2% PART I (preparatihttps://blog.faradars.org/wp-admin/post.php?post=510349&action=edit#on)
3% In this part the screen is cleared, any other functions, figures and
4% variables are also cleared. The name of the program is displayed.
5clc
6clear all
7disp('Voltage-source inverter with Sinusoidal-Pulse Width Modulated output')
8disp(' By Tamer Khatib ')
9disp('')
10%
11% PART II
12% In this part the already known variables are entered, the user is
13% asked to enter the other variables.
14% Vrin is the DC input voltage.
15Vrin=1;
16% f is the frequency of the output voltage waveform.
17f=input('The frequency of the output voltage, f = ');
18% Z is the load impedance in per unit.
19Z=1;
20% ma is the modulation index
21ma=input('the modulation index,ma, (0<ma<1), ma = ');
22% phi is load-phase-angle
23phi=input('the phase angle of the load in degrees = ');
24% fc is frequency of the carrier signal.
25fc=input('The frequency of the carrier signal= ');
26%
27% PART III
28% Calculating load parameters.
29%
30phi=phi*pi/180;
31% R and L are the load resistance and inductance respectively.
32R=Z*cos(phi);
33L=(Z*sin(phi))/(2*pi*f);
34%
35% PART IV
36% Calculating the number of pulses per period,N
37N=fc/f;
38%
39%PART V
40% Building the Sawtooth signal,Vt, the output voltage waveform, Vout,
41% and finding the beginning (alpha) and the end (beta)for each of the output pulses.
42%
43% In each period of the sawtooth, there is one increasing and decreasing part of
44% the sawtooth, thus the period of the output voltage waveform is divided into
45% 2N sub-periods, k is used as a counter of these sub-periods.
46% for calculation purposes each of these sub-periods is divided into 50 points, i.e., the
47% output voltage waveform period is divided into 100N points.
48% j is a counter inside the sub-period
49% i is the generalized time counter
50for k=1:2*N
51for j=1:50
52% finding the generalized time counter
53i=j+(k-1)*50;
54% finding the time step
55wt(i)=i*pi/(N*50);
56%finding the half period of the output voltage.
57if(sin(wt(i)))>0
58hpf=1;
59else
60hpf=-1;
61end
62% calculating the modulating signal.
63ma1(i)=ma*abs(sin(wt(i)));
64% calculating the sawtooth waveform
65if rem(k,2)==0
66Vt(i)=0.02*j;
67if abs(Vt(i)-ma*abs(sin(wt(i))))<=0.011
68m=j;
69beta(fix(k/2)+1)=3.6*((k-1)*50+m)/N;
70else
71j=j;
72end
73else
74Vt(i)=1-0.02*j;
75if abs(Vt(i)-ma*abs(sin(wt(i))))<0.011
76l=j;
77alpha(fix(k/2)+1)=3.6*((k-1)*50+l)/N;
78else
79j=j;
80end
81end
82% calculating the output voltage waveform
83if Vt(i)>ma*abs(sin(wt(i)))
84Vout(i)=0;
85else
86Vout(i)=hpf*Vrin;
87end
88end
89end
90beta(1)=[];
91% PART VI
92% Displaying the beginning (alpha), the end (beta) and the width
93% of each of the output voltage pulses.
94disp(' ')
95disp('......................................................................')
96disp('alpha beta width')
97[alpha' beta' (beta-alpha)']
98% PART VII
99% Plotting the , the triangular carrier signal, Vt,
100% the modulating signal and the output voltage waveform, Vout.
101a=0;
102subplot(2,1,1)
103plot(wt,Vt,wt,ma1,wt,a)
104axis([0,2*pi,-2,2])
105ylabel('Vt, m(pu)');
106subplot(2,1,2)
107plot(wt,Vout,wt,a)
108axis([0,2*pi,-2,2])
109ylabel('Vo(pu)');
110xlabel('Radian');
111% PART VIII
112% Analyzing the output voltage waveform
113% Finding the rms value of the output voltage
114Vo =sqrt(1/(length(Vout))*sum(Vout.^2));
115disp('The rms Value of the output Voltage = ')
116Vo
117% finding the harmonic contents of the output voltage waveform
118y=fft(Vout);
119y(1)=[];
120x=abs(y);
121x=(sqrt(2)/(length(Vout)))*x;
122disp('The rms Value of the output voltage fundamental component = ')
123x(1)
124%
125% Finding the THD of the output voltage
126THDVo = sqrt(Vo^2 -x(1)^2)/x(1);
127%
128% PART IX
129% calculating the output current waveform
130m=R/(2*pi*f*L);
131DT=pi/(N*50);
132C(1)=-10;
133%
134i=100*N+1:2000*N;
135Vout(i)=Vout(i-100*N*fix(i/(100*N))+1);
136%
137for i=2:2000*N;
138C(i)=C(i-1)*exp(-m*DT)+Vout(i-1)/R*(1-exp(-m*DT));
139end
140% PART X
141% Analyzing the output current waveform
142% finding the harmonic contents of the output current waveform
143for j4=1:100*N
144CO(j4)=C(j4+1900*N);
145CO2= fft(CO);
146CO2(1)=[];
147COX=abs(CO2);
148COX=(sqrt(2)/(100*N))*COX;
149end
150% Finding the RMS value of the output current.
151CORMS = sqrt(sum(CO.^2)/(length(CO)));
152disp(' The RMS value of the load current =')
153CORMS
154%Finding the THD for the output current
155THDIo = sqrt(CORMS^2-COX(1)^2)/COX(1);
156% PART XI
157% Finding the supply current waveform
158for j2=1900*N+1:2000*N
159if Vout(j2)~=0
160CS(j2)=abs(C(j2));
161else
162CS(j2)=0;
163end
164end
165% PART XII
166% Analyzing the supply current waveform
167%
168% Supply current waveform and its average value
169for j3=1:100*N
170CS1(j3)=abs(CS(j3+1900*N));
171end
172CSRMS= sqrt(sum(CS1.^2)/(length(CS1)));
173disp('The RMS value of the supply current is')
174CSRMS
175CSAV= (sum(CS1)/(length(CS1)));
176disp('The Average value of the supply current is')
177CSAV
178% Finding the Fourier analysis of the supply current waveform
179CS2= fft(CS1);
180CS2(1)=[];
181CSX=abs(CS2);
182CSX=(sqrt(2)/(100*N))*CSX;
183% PART XIII
184% Displaying the calculated parameters.
185disp(' Performance parameters are')
186THDVo
187THDIo
188a=0;
189%PART XIV
190% Opening a new figure window for plotting of
191% the output voltage, output current, supply current and the harmonic
192% contents of these values
193figure(2)
194subplot(3,2,1)
195plot(wt,Vout(1:100*N),wt,a);
196title('');
197axis([0,2*pi,-1.5,1.5]);
198ylabel('Vo(pu)');
199subplot(3,2,2)
200plot(x(1:100))
201title('');
202axis([0,100,0,0.8]);
203subplot(3,2,3)
204plot(wt,C(1900*N+1:2000*N),wt,a);
205title('');
206axis([0,2*pi,-1.5,1.5]);
207ylabel('Io(pu)');
208subplot(3,2,4)
209plot(COX(1:100))
210title('');
211axis([0,100,0,0.8]);
212ylabel('Ion(pu)');
213subplot(3,2,5)
214plot(wt,CS(1900*N+1:2000*N),wt,a);
215axis([0,2*pi,-1.5,1.5]);
216ylabel('Is(pu)');
217xlabel('Radian');
218subplot(3,2,6)
219plot(CSX(1:100))
220hold
221plot(CSAV,'*')
222text(5,CSAV,'Average valu')
223title('');
224axis([0,100,0,0.8]);
225ylabel('Isn(pu)');
226xlabel('Harmonic Order');