MATLAB电路仿真 实验报告

MATLAB电路仿真实验报告实验一直流电路实验目的1加深对直流电路的节点电压法和网孔电流法的理解。2学习MATLAB的矩阵运算方法。2实验内容编写以下程序，并记录程序和结果，写出简单注释。1电阻电路的计算 如图，已知：R1=2，R2=6,R3=12,R4=8,R5=12,R6=4,R7=2. (1)如Us=10V,求i3,u4,u7; (2)如U4=4V,求Us,i3,i7. （1）Z=[20-120;-1232-12;0-1218];V=[10;0;0];I=Z\V;IRB=I(1)-I(2);fprintf('thecurrentthroughR3is%8.4fAmps\n',IRB)U4=I(2)*8;U7=I(3)*2;fprintf('thesourcethroughR4is%8.4fV\n',U4)fprintf('thesourcethroughR7is%8.4fV\n',U7)结果：thecurrentthroughR3is0.3571AmpsthesourcethroughR4is2.8571VthesourcethroughR7is0.4762V（2）Z=[-12-12;018];V=[-16;6];I=Z\V;I(3)=0.5;U=I(1)*20-I(3)*12;fprintf('thesourceis%8.4fV\n',U)i3=I(1)-I(3);i7=I(2);fprintf('thecurrentthroughR3is%8.4fAmps\n',i3)fprintf('thecurrentthroughR7is%8.4fAmps\n',i7)结果thesourceis14.0000VthecurrentthroughR3is0.5000AmpsthecurrentthroughR7is0.3333Amps2求解电路里的电压，例如V1，V2，·····，V5Y=[1-12-20;05-1380;204-110;176-55-1960;00001];I=[0-200-120024]';V=inv(Y)*I;fprintf('V1=%fV\nV2=%fV\nV3=%fV\nV4=%fV\nV5=%fV\n',V(1),V(2),V(3),V(4),V(5))仿真结果：V1=117.479167VV2=299.770833VV3=193.937500VV4=102.791667VV5=24.000000V3如图，已知R1=R2=R3=4,R4=2,控制常数k1=0.5,k2=4,is=2,求i1和i2Z=[1000;-416-8-4;0010.5;0-846];V=[2000]';I=inv(Z)*V;i1=I(2)-I(3);i2=I(4);fprintf('i1=%fA\ni2=%fA\n',i1,i2)仿真结果：i1=1.000000Ai2=1.000000A3实验总结1、仿真前需进行准确的计算，列出节点或回路表达式方可列出矩阵惊醒计算。2、熟练矩阵运算公式，即：V=inv（Y）*I实验二直流电路（二）1实验目的1加深对戴维南定律，等效变换等的了解。2进一步了解MATLAB在直流电路的应用。2实验内容1在图2-3，当RL从0改变到50KΩ，绘制负载功率损耗。检验当RL=10KΩ的最大功率损耗。R=10;U=10;RL=10;P=U^2*(RL*1000)/((R+RL)*1000)^2RL=0:50;p=(RL*1000*U./((R+RL)*1000)).*U./((R+RL)*1000)figure(1),plot(RL,p),grid程序运行结果：P=0.0025p=Columns1through700.00080.00140.00180.00200.00220.0023Columns8through140.00240.00250.00250.00250.00250.00250.0025Columns15through210.00240.00240.00240.00230.00230.00230.0022Columns22through280.00220.00210.00210.00210.00200.00200.0020Columns29through350.00190.00190.00190.00180.00180.00180.0018Columns36through420.00170.00170.00170.00160.00160.00160.0016Columns43through490.00160.00150.00150.00150.00150.00140.0014Columns50through510.00140.00142在如图所示电路中，当R1取0,2,4,6,10,18,24,42,90和186Ω时，求RL的电压UL，电流IL和RL消耗的功率。A=[3/4-1/20;1/2-33/245/6;01-1];I=[1500]';U=inv(A)*I;us=U(3);R=6;Z=[02461018244290186];RL=Z(1,:),i=us./(R+RL)u=us.*RL./(R+RL)p=(RL.*us./(R+RL)).*us./(R+RL)figure(1),plot(RL,i),gridfigure(2),plot(RL,u),gridfigure(3),plot(RL,p),grid仿真结果：RL=02461018244290186i=Columns1through78.00006.00004.80004.00003.00002.00001.6000Columns8through101.00000.50000.2500u=Columns1through7012.000019.200024.000030.000036.000038.4000Columns8through1042.000045.000046.5000p=Columns1through7072.000092.160096.000090.000072.000061.4400Columns8through1042.000022.500011.62503实验总结1、经过这次实验基本了解了MATLAB变量生成的应用。2、经过这次实验更加深刻了戴维南等效电路的原理。3、了解了MATLAB中图像的生成。实验三正弦稳态1实验目的1学习正弦交流电路的分析方法。2学习MATLAB复数的运算方法。2实验内容1、如图所示电路，设R1=2,R2=3,R3=4,jxl=j2,-jXC1=-j3,-jXC2=-j5,Us1=8∠0°V,Us2=6∠0°,Us3=∠0°,Us4=15∠0°,求各电路的电流相量和电压向量。clear,formatcompactR1=2;R2=3;R3=4;ZL=2*j;ZC1=-3*j;ZC2=-5*j;US1=8;US2=6;US3=8;US4=15;Y1=1/R1+1/ZL;Y2=1/ZC1+1/R2;Y3=1/R3+1/ZC2;a11=1/Y1;a12=1/Y2;a13=1/Y3;a21=0;a22=-1;a23=1;a31=-1;a32=1;a33=0;b1=0;b2=US2/R2-US3/R3-US4/ZC2;b3=-US1/ZL-US2/R2;A=[a11,a12,a13;a21,a22,a23;a31,a32,a33];B=[b1;b2;b3];I=inv(A)*B;I1=I(1),I2=I(2),I3=I(3),ua=I1/Y1,ub=I3./(-Y3),I1R=ua/R1,I1L=(US1-ua)./ZL,I2R=(US2-ua+ub)/R2,I2C=(ua-ub)./ZC1,I3R=(US3-ub)/R3,I3C=(US4-ub)./ZC2程序运行结果：I1=1.2250-2.4982iI2=-0.7750+1.5018iI3=-0.7750-1.4982iua=3.7232-1.2732iub=4.8135+2.1420iI1R=1.8616-0.6366iI1L=0.6366-2.1384iI2R=2.3634+1.1384iI2C=1.1384-0.3634iI3R=0.7966-0.5355iI3C=0.4284+2.0373i2、含电感的电路：复功率如图，已知R1=4,R2=R3=2,XL1=10,XL2=8,XM=4,Xc=8,Us=10∠0°V,Is=10∠0°A.求电压源，电压源发出的复功率。clear,formatcompactR1=4;R2=2;R3=2;XL1=10;XL2=8;XM=4;XC=8;US=10;IS=10;Y1=1/R1+1/(-j*XC);Y2=1/(j*(XL1-XM));Y3=1/(j*XM);Y4=1/(j*(XL2-XM)+R2);Y5=1/R3;a11=1;a12=-1;a13=0;a14=0;a15=0;a21=0;a22=0;a23=0;a24=1;a25=-1;a31=0;a32=1;a33=-1;a34=-1;a35=0;a41=1/Y1;a42=1/Y2;a43=1/Y3;a44=0;a45=0;a51=0;a52=0;a53=-1/Y3;a54=1/Y4;a55=1/Y5;A=[a11,a12,a13,a14,a15;a21,a22,a23,a24,a25;a31,a32,a33,a34,a35;a41,a42,a43,a44,a45;a51,a52,a53,a54,a55];B=[-US/R1;-IS;0;0;0];I=inv(A)*B;I1=I(1);I2=I(2);I3=I(3);I4=I(4);I5=I(5);ua=-I1/Y1;ub=I3/Y3;uc=I5/Y5;Ii=US/R1+ua/R1;Pus=US*IiPis=uc*IS程序运行结果：Pus=54.0488-9.3830iPis=1.7506e+002+3.2391e+001i4、正弦稳态电路，利用模值求解如图所示电路，已知IR=10A，Xc=10Ω，并且U1=U2=200V，求XL。clearU2=200;IR=10;R=U2/IR;XC=10;U=[200*exp(-150j*pi/180);200*exp(-30j*pi/180)];I=(U-200)./(-j*XC);X=200./(I-10);XL=imag(X)仿真结果：XL=5.359074.64103实验总结学习了正弦交流电路的分析方法，初步了解了MATLAB向量图的绘制，虽然并不能说完全掌握，但是基本有了一定的了解。实验四交流分析和网络函数1实验目的1学习交流电路的分析方法2学习交流电路的MATLAB分析方法2实验内容1电路显示如图4-2，求电流i1(t)和电压uc(t)Z=[10-j*7.5-6+j*5;-6+j*510+j*3];U2=2*exp(pi*75*j/180);U=[5;U2];I=Z\U;I1=I(1);Uc=-j*10*(I(1)-I(2));i1_abs=abs(I1);i1_ang=angle(I1)*180/pi;uc_abs=abs(Uc);uc_ang=angle(Uc)*180/pi;fprintf('currentI1,magnitude:%f\n',i1_abs)fprintf('currentI1,angleindegree:%f\n',i1_ang)fprintf('voltageUc,mangnitude:%f\n',uc_abs)fprintf('voltageUc,angleindegree:%f\n',uc_ang)结果currentI1,magnitude:0.597294currentI1,angleindegree:13.266138voltageUc,mangnitude:3.202746voltageUc,angleindegree:-28.9807862如图，显示一个不平衡wye-wye系统，求相电压VAN，VBN和VCN。Ua=110;Ub=110*exp(pi*(-120)*j/180);Uc=110*exp(pi*120*j/180);Za1=1-j;Zb1=1-j*2;Zc1=1-j*0.5;Za2=5-j*12;Zb2=3-j*4;Zc2=5-j*12;Uan=Ua*Za2/(Za1+Za2);Ubn=Ub*Zb2/(Zb1+Zb2);Ucn=Uc*Zc2/(Zc1+Zc2);disp('UanUbnUcn')disp('幅值'),disp(abs([Uan,Ubn,Ucn]))disp('相角'),disp(angle([Uan,Ubn,Ucn])*180/pi)ha=compass([Uan,Ubn,Ucn]);set(ha,'linewidth',3)结果UanUbnUcn幅值99.875576.2713103.1342相角-2.1553-116.8202116.9789UanUbnUcn幅值99.875576.2713103.1342相角-2.1553-116.8202116.97894实验总结了解运用MATLAB分析交流电路。实验五动态电路1实验目的1学习动态电路的分析方法2学习动态电路的MATLAB计算方法2实验内容1、激励的一阶电路已知R=2欧姆，C=0.5F,电容初始电压Uc(0+)=4V，激励的正弦电压Us(t)=Umcoswt，其中w=2rad/s。当t=0时，开关s闭合，求电容电压的全响应，区分其暂态响应与稳态响应，并画出波形uc0=4;w=2;R=2;C=1;Zc=1/(j*w*C);dt=0.1;t=0:dt:10;us=6*cos(w*t);%È¡Um=6T=R*C;ucf=us*Zc/(Zc+R);uc1=uc0*exp(-t/T);figure(1);subplot(3,1,1);h1=plot(t,ucf);grid,set(h1,'linewidth',2)subplot(3,1,2);h2=plot(t,uc1);grid,set(h2,'linewidth',2);uc=ucf+uc1;subplot(3,1,3);h3=plot(t,uc);grid,set(h3,'linewidth',2)程序运行结果：2、二阶欠阻尼电路的零输入响应如图所示的二阶电路，如L=0.5H，C=0.02F。初始值uc（0）=1V，iL=0，试研究R分别为1Ω，2Ω，3Ω，…，10Ω时，uc（t）和iL(t)的零输入响应，并画出波形。R=1clear,formatcompactL=0.5;R=1;C=0.02;uc0=1;iL0=0;alpha=R/2/L;wn=sqrt(1/(L*C));p1=-alpha+sqrt(alpha^2-wn^2);p2=-alpha-sqrt(alpha^2-wn^2);dt=0.01;t=0:dt:1;num=[uc0,R/L*uc0+iL0/C];den=[1,R/L,1/L/C];[r,p,k]=residue(num,den);ucn=r(1)*exp(p(1)*t)+r(2)*exp(p(2)*t);iLn=C*diff(ucn)/dt;figure(1),subplot(2,1,1),plot(t,ucn),gridsubplot(2,1,2)plot(t(1:end-1),iLn),gridR=2R=3R=4R=5R=6R=7R=8R=9R=103实验总结1学习动态电路的分析方法。2了解MATLAB暂态电路的计算方法。实验六频率响应1实验目的1学习有关频率响应的相关概念2学习MATLAB的频率计算2实验内容1、一阶低通电路的频率响应如图为一阶RC低通电路，若以Uc为响应，求频率响应函数，画出其幅频响应（幅频特性）∣H（jw）∣和相频的响应（相频特性）clear,formatcompactww=0:0.2:4;H=1./(1+j*ww);figure(1)subplot(2,1,1),plot(ww,abs(H)),grid,xlabel('ww'),ylabel('angle(H)')subplot(2,1,2),plot(ww,angle(H))grid,xlabel('ww'),ylabel('angle(H)')figure(2)subplot(2,1,1),semilogx(ww,20*log(abs(H)))grid,xlabel('ww'),ylabel('dB')subplot(2,1,2),semilogx(ww,angle(H))grid,xlabel('ww'),ylabel('angle(H)')仿真结果：(a)线性频率响(b)对数频率响2、频率响应：二阶低通电路令H0=1，画出Q=1/3,1/2,1/√2,1,2,5的幅频相频响应，当Q=1/√2时，成为最平幅度特性，即在通带内其幅频特性最为平坦。clear,formatcompactforQ=[1/3,1/2,1/sqrt(2),1,2,5]ww=logspace(-1,1,50);H=1./(1+j*ww/Q+(j*ww).^2);figure(1)subplot(2,1,1),plot(ww,abs(H)),holdonsubplot(2,1,2),plot(ww,angle(H)),holdonfigure(2)subplot(2,1,1),semilogx(ww,20*log10(abs(H))),holdonsubplot(2,1,2),semilogx(ww,angle(H)),holdonendfigure(1),subplot(2,1,1),grid,xlabel('w'),ylabel('abs(H)')subplot(2,1,2),grid,xlabel('w'),ylabel('angle(H))')figure(2),subplot(2,1,1),grid,xlabel('w'),ylabel('abs(H)')subplot(2,1,2),grid,xlabel('w'),ylabel('angle(H)')(a)线性频率响(b)对数频率响3、频率响应：二阶带通电路clear,formatcompactH0=1;wn=1;forQ=[5,10,20,50,100]w=logspace(-1,1,50);H=H0./(1+j*Q*(w./wn-wn./w));figure(1)subplot(2,1,1),plot(w,abs(H)),grid,holdonsubplot(2,1,2),plot(w,angle(H)),grid,holdonfigure(2)subplot(2,1,1),semilogx(w,20*log10(abs(H))),grid,holdonsubplot(2,1,2),semilogx(w,angl