Re: Active Regulation of DC Resonant Chargers


I called Ross Engineering and inquired about their HV dividers.  They make
a 15 and 30 kV divider applicable to our specifications.  Mr. Ross
recommended a 30 kV divider if rectifying a 14.4 kV pig.  He does not
recommend a wideband or compensated divider for DC or 60 Hz.  The dividers
are fixed at the buyers requirement, example 1000:1.  They have very high
input impedance, usually 300 megaohms.  So, divider output current is very

Price for the 30 kV DC HV divider? --------   $900.00.

No doubt an accurate HV divider can be built using HV, high wattage,
precision resistors like those Victoreen resistors, the likes of which R.
Hull is so fond.


> On each charging pulse a regulation circuit monitors the HV divider,
> and when the desired primary voltage is reached, the regulator fires 
> an SCR which is connected to the shunt winding of the reactor.  The
> SCR diverts the remaining stored reactor energy into a resistor bank,
> and the voltage on the primary cap stops promptly at the set point.
> This circuit works quite well, and the pulse-to-pulse accuracy is
> limited only by the accuracy of the HV divider and regulator circuit.
> Compensated dividers with better than 1% accuracy are commercially
> available from Ross Engineering.