Error in step size/solver Ode15s

• I am getting the following error while simulating my simulink model. Can anyone suggest?
• Derivative of state '8' in block 'hinf/LTI System3/Internal' at time 7.1111878193508238 is not finite. The simulation will be stopped. There may be a singularity in the solution. If not, try reducing the step size (either by reducing the fixed step size or by tightening the error tolerances)

Answer 1

[Prabhan Purwar]

Hi,

This problem occurs when an integrator is present in the model.

Open Configuration Parameter, set the diagnostic "Inf or NaN block output" to error, you will get the error as follows:

An error occurred while running the simulation and the simulation was terminated

Caused by:

• Block 'BlockName' outputs 'NaN' for element x of output port x at major time step 0

where BlockName is the block in which error is thrown.

This blocks has a divide by zero, which creates a Inf that when fed to an Integrator, generates this error.

So, avoid division by zero in the logic.