I notice that the output in the scope appears more or less correct but the curve is jagged and not smooth. I can reduce the step size or tolerances and the output becomes more smooth, but this is at a cost of simulation speed. Is there a better solution?
Although a simulation may meet the acceptable error constraint, the response rendered by the scope may appear jagged for larger time steps. To improve the rendering, the time step can be decreased by reducing the relative tolerance or limiting the maximum step size. However, the most efficient means of improving the rendering is to increase the refine factor.
The Refine Factor setting is an efficient method for generating additional output points in order to achieve smoother results. For each successful integration step, the solver calculates intermediate steps by interpolating the continuous states based on a higher-order polynomial. This is computationally much cheaper than reducing the maximum step size since the information has already been calculated.
In PLECS Blockset the Refine Factor is found in the Data Import/Export pane of the Configuration Parameters of the Simulink model. The setting in PLECS Standalone is found in the Solver pane of the Simulation Parameters window.
Note that a refine factor setting of less than 10 is recommended.