Problem in finding inverse Laplace
조회 수: 1 (최근 30일)
이전 댓글 표시
I have a problem with finding inverse laplace of function with Matlab. I obtained following transfer function :
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/151491/image.jpeg)
I tried methods like
syms s t;
num=[0 0 0 1.658e24 -1.163e14 6.076e15];
den=[1 3.334e09 1.005e15 1.675e24 5.025e27 1.675e33];
numsym=poly2sym(num);
densym=poly2sym(den);
transfer=numsym./densym;
ilaplace(transfer,s,t)
but did not get any result. Also I tried to use partial fraction expansion and I wrote transfer function respect to poles and zeros but when I added all the pieces I did not get the original transfer function.
syms s t;
num=[0 0 0 1.658e24 -1.163e14 6.076e15];
den=[1 3.334e09 1.005e15 1.675e24 5.025e27 1.675e33];
numsym=poly2sym(num);
densym=poly2sym(den);
transfer=numsym./densym;
[z,p,r]=residue(num,den);
transfer1=(z(1)/(s-p(1)))+(z(2)/(s-p(2)))+(z(3)/(s-p(3)))+(z(4)/(s-p(4)))+(z(5)/(s-p(5)));
transfer1=vpa(simplifyFraction((transfer1),'Expand',true),2)
The transfer1 variable after simplification is order 4 in numerator while the original transfer function is order 2. I would be very thankful if anyone help me to find the transfer function of following expression by any method?
댓글 수: 0
답변 (1개)
Azzi Abdelmalek
2015년 6월 23일
num=[0 0 0 1.658e24 -1.163e14 6.076e15];
den=[1 3.334e09 1.005e15 1.675e24 5.025e27 1.675e33];
numsym=poly2sym(num,'s');
densym=poly2sym(den,'s');
transfer=numsym./densym;
H=ilaplace(transfer)
참고 항목
카테고리
Help Center 및 File Exchange에서 Symbolic Math Toolbox에 대해 자세히 알아보기
제품
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!