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"Matrix has zero on diagonal" (AC/DC in 3D)

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Has anyone encountered this error in 3D ac/dc quasi-static model?

I found this error can occur even with a single elementary shape without any physics setting.

Is this a bug or did I do anything wrong?

Thanks.

3 Replies Last Post 2010年9月9日 GMT-4 17:25
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Posted: 1 decade ago 2010年7月6日 GMT-4 13:42
I faced with the same problem and I don't know what to do.
I faced with the same problem and I don't know what to do.

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Posted: 1 decade ago 2010年8月16日 GMT-4 03:00
I have also the same problem with the same task (AC/DC, Quasi-static). In more details i have the cable model putted in the air and connected to the pspice circuit. Ich have perfectly done the similar task in 2D but in 3d mode - no chance:
"Failed to find consistent initial values. Matrix has zero on diagonal. Last time step is not converged". I have tried all what i know - changed in wide range the step size; different solving methods; pspice impulse begins not from null:
"I_IN 1 0 PULSE(1 100000 1e-7 10e-6 700e-6 0.1e-6)". And i dont know what can i do more.. ill be obliged to everyone help me.
I have also the same problem with the same task (AC/DC, Quasi-static). In more details i have the cable model putted in the air and connected to the pspice circuit. Ich have perfectly done the similar task in 2D but in 3d mode - no chance: "Failed to find consistent initial values. Matrix has zero on diagonal. Last time step is not converged". I have tried all what i know - changed in wide range the step size; different solving methods; pspice impulse begins not from null: "I_IN 1 0 PULSE(1 100000 1e-7 10e-6 700e-6 0.1e-6)". And i dont know what can i do more.. ill be obliged to everyone help me.

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Posted: 1 decade ago 2010年9月9日 GMT-4 17:25
With the current solver, u dont have to have zero conductivity, try to change solver or set a non-zero conductivity. when u reached the convergence try to reduce sigma.
With the current solver, u dont have to have zero conductivity, try to change solver or set a non-zero conductivity. when u reached the convergence try to reduce sigma.

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