The question is deeper than I thought. How do higher PWS voltages change things?

[GT Blocker]

Hey all;

I posted a question in the HH project section and in an after thought, I realized, perhaps not in the right place - http://www.geotech1.com/forums/showt...ges-and-MOSFET . Please read the thread before mentioning MOSFETs, etc..

The question revolves around the influence of higher initial coil voltages and how they will (or might) effect the entire process of coil attack and decay.
Will a higher coil voltage pulse require more dampening?, for example.

I figure the stupid questions are those un-asked, sooo... Any thoughts?

Thanks,
GTB

[Mechanic]

Hi GTB,

No, the damping is set to coil capacitance/inductance which remain the same. Once you have the damping resistor set to a specific coil it will remain the same no matter what voltage you drive it with, unless you change the tx mosfet and the new one has different capacitance. What will happen though is the eddy currents induced into the target during the tx on period will be higher and these will need to be cancelled during the flyback period before the eddy currents produced by the flyback period will start to build up to the eddy current decay we see in the off time period. If the current in the coil is allowed to flat top during the tx on period then the tx on eddy currents will start to decay away before the flyback period, allowing the flyback period to be more productive in producing usable eddy currents for large targets. For smaller targets I don't think there will be much difference.

Cheers Mick