Re: Just an idea

Carlos,

Thank you for the kind words and will do. The problem with caps is
energy density, i.e. how many watt-hours can be stored per unit
volume. Doing violence to a differential equation yeilds:

C = I dt / dv

If I is 25 Amps, dt is 1 second and dv is 2.5 volts (10% drop on a 25
VDC charged cap), then C equals 10 farads or 10,000,000 microfarads.
Figuring an energy density of 3000 uF @ 25VDC per cubic inch (Al,
lytic) results in a capacitor volume of 3,333 cu-in or, a cube 15
inches on a side. Possible but not practical. Can you imagine the
BANG it would make if you reversed the polarity though...?

Mariss

> Even simpler, couldn't you just use really BIG caps and avoid the

battery

> charging circuitry?
>
> By the way, I'm impressed by what you guys are doing, and am very

eager to

> hear more about your upcoming step/dir servo amps.
>
> Carlos Guillermo
> VERVE Engineering & Design