Sine wave block produces a triangular wave when the "pi" value is in the frequency.

[Stephen Ofori]

when the pi is there it produces a triangular waveform

Answer 1

[nick]

Hi Stephen,

I understand from your query that you need help understanding why the sine wave output appears as a triangular wave when the frequency is set to 100*pi.

I assume you haven't altered any of the solver settings. The issue may be due to a larger time step, which results in the output of the "sine" block not being captured accurately. To rectify this:

1. Navigate to the "Configuration Parameters" dialog. This can usually be done by clicking on a gear icon.
2. In the "Configuration Parameters" dialog, locate the "Solver" tab.
3. Within the "Solver" tab, find the "MaxStepSize" setting.
4. Change the value of "MaxStepSize" to a smaller number, such as 1e-6.
5. Apply the changes by clicking "OK" or "Apply" in the dialog.

While the simulation may take longer, this adjustment will provide more data points and, consequently, a smoother curve. Here is the obtained output:

Figure 1 Output of Sine Wave at “MaxStepSize” 1e-6

Kindly refer to the following documentation to learn more about solver selection:

https://www.mathworks.com/help/simulink/ug/choose-a-solver.html

Hope this helps,

Regards,

Neelanshu