Reproducing Simulations from Article with Classical Control Methods

[Salma N]

Hello everyone,

I am working on reproducing the simulations presented in the article titled "Voltage Stability and Loadability Improvement of DC Microgrid Connected with Static and Dynamic Loads" by R. B. Thogaru et al. I aim to achieve the results using only classical control methods, specifically a simple PID or PI controller.

I am encountering the following difficulties:

1. System Design: I am unsure how to dimension components like the solar PV panels and the DC-DC boost converter.


2. Load Discontinuity Simulation: I need help modeling intermittent loads (both static and dynamic).


3. PID Tuning: I struggle with setting the correct PID parameters for stable and optimal control.



Any guidance, resources, or suggestions would be greatly appreciated. If anyone has experience with similar systems or has tackled these challenges before, I would love to learn from your insights.

Thank you in advance for your support!

 

[BradtheRad]

A PV panel yields highest current to a zero Ω load. It outputs greatest voltage to infinite Ω. In both cases zero work is done. As it turns out there is some midway volt level and some midway Amperes that provides maximum power. This is the finding of my own tests of different raw PV panels in sunlight with various resistive loads.

A microgrid power converter is liable to draw different Amperes at different times in a cycle. The commercial rating of your PV panel is probably the best guide to optimum utilization. I believe a manufacture assembles enough individual PV cells in series, so as to obtain a panel with practical usefulness. For instance, high enough voltage to completely charge a car battery. However its greatest power output might be at 12 volts, therefore the manufacturer gives it a commercial rating of 12V @ 1A. Or 12V @ 2A. Etc.

Such variations in power output are difficult to model even if they are predictable. In real life the aim is to draw smooth optimum Amperes. Therefore it's worth it to consider putting a hefty capacitor (integrator) at the converter input. And, probably an inductor in series immediately at panel output. As a result PV output does not jump up and down even as converter drain is for intermittent current.