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Attempt to evaluate negative power of zero error
Posted 2023/09/15 19:11 GMT-4 1 Reply
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Hi,
I am trying to simulate the Bfield and E field induced by two loop coils. I am defining them numerically and in the coil geometry analysis step, I get this error for my second coil which is the mirror of the first one. The model with one coil works well but when I add a second coil, it gives me this message:
*Segregated Step 1 Attempt to evaluate negative power of zero. - Function: ^ Failed to evaluate temporary symbolic derivative variable. - Variable: comp1.mf.coil2.ccc1.normg@VDN$2comp1.mf.coil2.ccc1.pYm.internal - Defined as: ((-exp((-i)phase))(2comp1.mf.coil2.ccc1.gY))(((((comp1.mf.coil2.ccc1.gX^2)+(comp1.mf.coil2.ccc1.gY^2))+(comp1.mf.coil2.ccc1.gZ^2))^(-0.5))0.5) Failed to evaluate temporary symbolic derivative variable. - Variable: comp1.mf.coil2.ccc1.weak1@VDN$2{test@2}@VDN$2comp1.mf.coil2.ccc1.pYm.internal Failed to evaluate expression. - Expression: (-(((((-exp((-i)phase))(2comp1.mf.coil2.ccc1.gY))(((((comp1.mf.coil2.ccc1.gX^2)+(comp1.mf.coil2.ccc1.gY^2))+(comp1.mf.coil2.ccc1.gZ^2))^(-0.5))0.5))comp1.mf.coil2.ccc1.Vdom)((-comp1.mf.coil2.intmtcd(eps+comp1.mf.coil2.ccc1.normg))/((eps+(comp1.mf.coil2.ccc1.normgcomp1.mf.coil2.ccc1.Vdom))^2))))dvol Failed to evaluate Jacobian of expression. - Expression: (comp1.mf.coil2.ccc1.S-(comp1.mf.coil2.intmtcd(eps+comp1.mf.coil2.ccc1.normg)/(eps+(comp1.mf.coil2.ccc1.normgcomp1.mf.coil2.ccc1.Vdom))))dvol Failed to evaluate Jacobian of expression. - Expression: (comp1.mf.coil2.ccc1.weak1)(dvol)**
I understand that I must have a variable that becomes 0 to a negative power but I don't understand what the variables comp1.mf.coil2.ccc1.gX, comp1.mf.coil2.ccc1.gY or comp1.mf.coil2.ccc1.gZ might represent.
Thanks in advance for your help
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I don't know those variables either, but I'm guessing (and it's just a wild guess) that this may have something to do with the fact that you mirrored the first coil to make the second coil, and that this action may have led to improper boundary conditions (or other specs, such as material properties) in the model. I encourage you to post your .mph file to the forum, so that the specific issue(s) in your particular model will be easier to identify.
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