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From: piglet <erichpwagner@hotmail.com>
Newsgroups: sci.electronics.design
Subject: Re: Interesting inductor
Date: Thu, 14 Mar 2024 13:03:07 -0000 (UTC)
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john larkin <jl@650pot.com> wrote:
> On Wed, 13 Mar 2024 22:32:27 +0000, Clive Arthur
> <clive@nowaytoday.co.uk> wrote:
> 
>> On 13/03/2024 04:18, John Larkin wrote:
>> 
>> <snip>
>> 
>>> I'm hassling with inductors now too, but at the other end of the speed
>>> spectrum.
>>> 
>>> We want a programmable inductor, from maybe 1 mH to 500 mH or so,
>>> maybe 100 mA. Sounds like an inductive DAC, a series string of
>>> inductors with shorting relays. If the step inductance ratio were,
>>> say, 1.8:1 we could have some hidden bits, more than the customer
>>> sees, so we could get pretty close to his requested value.
>>> 
>>> We could test all 2^n steps, make a list, and select the closest to
>>> his request.
>>> 
>>> We're simulating loads to an engine control computer, torque motors
>>> and solenoids and steppers.
>>> 
>> 
>> Gyrator?
> 
> We just yesterday had a brainstorm session about that. How can one
> make a programmable electronic fake inductor?
> 
> A real inductor stores energy, and can do things like high voltage
> flyback. So a fake inductor should store energy, or pretend to. It
> could be done with a current shunt, a fast ADC, some math in an FPGA,
> a fast DAC, and a big power amplifier with big power supplies. Too
> much work.
> 
> 

I wonder if you could reduce the power supply needs a bit by switchmoding
the incoming current into big storage capacitors so the gyrator does some
energy storage and could make flybacks up to some limit?

-- 
piglet