Energy Harvesting using Piezo and MEMS Extension

Good Morning,

I am building a cantilevered beam piezo model with adjacent resistor to measure power generated.  I am using the Piezo and MEMS extension in workbench.  While using the example "Piezo fan" with the extension, I am able to run the model with success.  I am able to get a voltage response.

Now, I need to add a resistor (CIRCU94) element and measure power being generated during a harmonic response simulation.  Attached is my archived WB project.  The project shows the successful model without the resistor.  It also shows the unsuccessful model with an attempt to add the resistor.  Would you please help me figure out how to get the resistor to work?

Thank you,

Phil Jones

Penn State, Erie, PA


  • jonespa87jonespa87 Member
    edited December 2018

    Good Morning,

    I am able to get the simulation to run now.  However, it is still not recognizing the CIRCU94 element and nodes.  Hum.  I will attach the latest project schematic for your assistance.

    Thank you,


  • jonespa87jonespa87 Member
    edited January 2019

    I figured out my error.  I just needed to use the nodes already present on the beam element for the resistor.  It seems to be working now.

  • Punnag ChatterjeePunnag Chatterjee Raleigh, NCMember
    edited February 2019

    Hi Jones,


    Is it possible to attach the final error free workbench archived file here so I can learn from it and use it for a different application? Thanks in advance.

  • jonespa87jonespa87 Member
    edited February 2019

    Sure.  The project schematic shows the isotropic modal, the harmonic response without a load resistor, and then there is the anisotropic harmonic response with the load resistor.  I hope it helps.

    Phil Jones

  • jj77jj77 Member
    edited February 2019

    Great jonespa87, very interesting.


    I did a small example, to show, basically connecting the circu94 to the existing mesh on pzt patch, that was missing initially.


    Now it is coupled to the plate via the ACT coupling, very nice.


    Thanks again for posting this

  • jonespa87jonespa87 Member
    edited March 2019

    Good Morning,

    I have a new question about the Piezo and MEMS extension usage for energy harvesting.

    My workbench model has been running fine.  I am able to simulate voltage response using various resistor values on my CIRCU94 element.

    However, when I use a low resistance (for example < 7000 ohms), the simulation solves but the voltage response result has a red lightning bolt and no voltage response plot is generated.  It seems as though when it gets close to "closed" circuit, the voltage response will not be produced.

    Is there something I need to change in the settings to get a result with low resistance?

    Thank you,


  • nilszbhnilszbh Member
    edited June 2019



    I am using the same extension to model a piezoelectric harvester, and having some questions in my simulation:


    1- I get very high and very low voltages (varying from 10e-6  to 10e6 volts). I have defined a ground voltage node, but still getting weird voltages. 

    2- voltage is not defined for all the parts of the model. I have the error of: 

    "The user defined result might not be calculated successfully wholly or in some areas.

        There are some elements (or nodes) which do not contain

        data for the expression in: 310HARMONIC = VOLT


        Note that the result data may not be contained in the result file

        or may not be applicable to some element types.

        Also note that the solver module can create elements,

        such as surface effect or interface elements,

        whose results cannot currently be scoped in a contour display."


    3- the solver doesn't let me define the ground voltage on the same node that I have voltage coupling with one side of my piezo components. The error  I get is : 


    "Specified constraint not allowed on slave degree of freedom in coupled 
      Coupled set number 1 First node= 222 Slave node = 31935 Degree of     
     freedom = VOLT.                                                        
      Move Move constraint to first node or remove coupling and constrain   

     all.  " 


    I would appreciate if you could give me any related tips. Thanks in advance!

  • GuoyangGuoyang Member
    edited November 2019

    Hi, I met this problem as well. Have you known how to solve it? 

  • MaiRabieMaiRabie Member
    edited June 20


    good day!

    I am trying to regenerate the same piezoelectric harvester you modeled. However, the voltage output turns to be always zero. Am I missing any information here?

    Thanks in advance



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