Hi Huiliu.
Thank you for the response. I am using ANSYS 2020 and Piezo&MEMS Extension. It is compatible with the edition used since I performed an analysis for a piezoelectric actuator before. In that analysis, there was just one piezo patch. Right now, I am trying to conduct an energy harvesting analysis with 4 piezoelectric sensors, thus, obtain the voltage output and plot the voltage frequency responses for each piezoelectric sensor. For this reason, I define voltage couplings for each face of the piezoelectric sensors and apply zero voltage (ground) for the top faces. However, I receive the voltage coupling errors as mentioned above. When I just keep one voltage coupling and suppress the others, the analysis runs. I do not understand why it happens. As you said, I checked the element types from the solve file. It seems all right.
Secondly, when I run the analysis with just one voltage coupling for one piezo, I come up with the errors for plotting the voltage responses, as mentioned above. Can it be due to the polarization of the piezoelectric sensor??
Thank you in advance
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2    192 SOLID226   0.062  0.000326
3    160 SOLID226   0.125  0.000781
4    160 SOLID226   0.078  0.000488
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10    337 CONTA174   0.000  0.000000
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