I’ve had a hard time identifying good industry rules of thumb for conservative controls design. So I’ve started a category on the wiki named “Rules of Thumb”.

These rules of thumb should provide inexperienced controls engineers with guidelines to a good design. For experienced engineers, I hope we will find these rules of thumbs to be informative about how other industries design their systems. We may even find that another industry’s common practices make sense for our own.

Please add whatever rules of thumb your industry uses.

Clean Energy: The Sterling Engine

A while back I came across the Sterling engine.  The Sterling engine takes waste heat and turns it into piston motion.  Obviously if it moves we can generate electricity from the motion.

The main problem with Sterlings is the efficiency of the power extraction.  Using waste heat the available energy for extraction is significantly less than the original fuel.

Wind Turbines and Controls

Wind turbines faced a similar energy extraction problem.  The folks at NREL chose some advanced controls to extract the maximum amount of energy from the available wind.  With wind there isn’t a consistent energy source and maximizing its extraction is key to making the technology economically viable.

Controls…

The available energy for extraction is small.  Like the wind turbines, Sterlings need control to maximize the energy extraction.

Thoughts?

I find the Bode plot to be one of the most useful tools in all of Classical controls.  This is probably no surprise to anyone who works in the field.  Many of its uses are obvious.  However, I always wondered if there were a way to determine stability from the Bode plot.  After giving it some thought I assumed there was no way to determine if the pole had a positive or negative real part.  However, the Google group for controls has a topic on determining stability from the Bode plot.  Here’s the link.