This is because the voltage waveform after the rectifier bridge is viewed as the superposition of DC component [U.sub.dc] and the ideal sawtooth waveform
In the simulation n = 3, which determines the approximate value of the frequency ratio in the digital part and the frequency of the sawtooth waveform
[f.sub.s] / f [approximately equal to] 8.
This raises the cloud-to-ground potential difference, causing breakdown to reoccur multiple times and creating a crude sawtooth waveform
. This charge-discharge cycle continues until sufficient charge has been neutralized that breakdown during this strike event can no longer occur.
The switch control signal, which controls the state (on or off), in PWM switching, is generated by comparing a signal level control voltage [v.sub.control] with a repetitive waveform (sawtooth waveform
Frequently, half-sine and sawtooth waveforms
are applied by the drop table or electrodynamic shaker.