Error with solve function
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I'm trying to solve these equations and find I1,I2,I3 but when I run it it gives me an error
syms I1 I2 I3
eqn1 = I1*(R_s + X_s) + I3*X_m == V1;
eqn2 = (I2*(X_r + R_r + Z1))/(I3*X_m) == 0;
eqn3 = I1 + I3 - I2 == 0;
S = solve([eqn1,eqn2,eqn3],[I2,I2,I3]);
I1sol = S.I1;
I2sol = S.I2;
I3sol = S.I3;
1 个评论
@Maria Sarcos, It seems you are using the same variable I2 twice to solve the equations. See @Ameer Hamza answer where he used all three variables
syms I1 I2 I3 R_s X_s X_m V1 X_r R_r Z1
eqn1 = I1.*(R_s + X_s) + I3.*X_m == V1;
eqn2 = (I2.*(X_r + R_r + Z1))./(I3*X_m) == 0;
eqn3 = I1 + I3 - I2 == 0;
% ------------------------->> use I1 in place of I2
S = solve([eqn1,eqn2,eqn3],[I1,I2,I3]);
I1sol = S.I1
I2sol = S.I2
I3sol = S.I3
回答（1 个）
Ameer Hamza
2020-10-23
You also need to define other variables as symbolic
syms I1 I2 I3 R_s X_s X_m V1 X_r R_r Z1
eqn1 = I1*(R_s + X_s) + I3*X_m == V1;
eqn2 = (I2*(X_r + R_r + Z1))/(I3*X_m) == 0;
eqn3 = I1 + I3 - I2 == 0;
S = solve([eqn1,eqn2,eqn3],[I1,I2,I3]);
I1sol = S.I1;
I2sol = S.I2;
I3sol = S.I3;
3 个评论
Maria Sarcos
2020-10-23
Ameer Hamza
2020-10-23
What is the error? Which numbers are imaginary?
Maria Sarcos
2020-10-23
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2020-10-23
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