Hi @DIMAS
You are likely seeking general solutions without needing someone to guide you through the process step-by-step. The deviation of the MPPT output response from the desired MPPT setpoint during steady state is referred to as steady-state error. This steady-state error can typically be eliminated or reduced by the following methods:
- Scale the setpoint accordingly.
- Add an integrator (which requires tuning the integral gain).
- Eliminate the disturbance source that causes the deviation.
Based on the graph and my experience as a grapher (rather than as an MPPT expert), the steady-state errors appear to be induced by different MPPT setpoints. Therefore, Method #1 should address the issue. However, you must determine the scaling gain values at different setpoints. If you are proficient in graphing, you should be able to find a mathematical model that fits the scaling gain values (y-axis) at various setpoints (x-axis). Check out Curve Fitting Toolbox.
Alternatively, a straightforward approach would be to implement If–Else logic to switch between different scaling gain values. If there are only three fixed setpoints, as shown in the graph, the If–Else method is a more economical solution. Industrial control practitioners often prefer this math-free approach because most production lines do not many setpoints.
