When a signal pulses on and off, the duty cycle describes how much of each cycle is spent in the "on" state. A 50% duty cycle means on half the time, off half the time (a symmetric square wave). A 10% duty cycle means short bursts with long pauses.
Duty cycle = (on-time / total period) × 100%
Why it matters
In pulsed excitation experiments, the duty cycle is a critical variable. Many of the 768 patents in the Open Energy analysis specify low duty cycles — 5% to 20% — meaning the system receives energy in short, sharp bursts with long recovery periods between them.
The hypothesis is that the "off" period isn't idle — the resonant system is ringing, the non-linear element is processing harmonics, and the back-EMF recovery circuit is capturing returned energy. A lower duty cycle gives the system more time to do this processing between pulses.
This is counterintuitive: less drive time can mean more energy output. But it's consistent with how resonant systems work — overdrive them and you damp the resonance; pulse them and let them ring, and the resonance builds.