Can a DC Motor in a Chopper Circuit Generate AC for a Transformer?

AI Thread Summary
A DC motor cannot effectively generate AC for a transformer in a chopper circuit, as it would primarily produce pulsing DC current, risking transformer core saturation. The small gaps in a motor's commutator lead to minimal interruptions in current flow, resulting in inefficient voltage pulses on the secondary side. Instead, using a self-switched relay or transistors for switching is recommended to achieve better results. If a relay is used, it must be capable of reversing current direction with double pole double throw switches. For applications like driving a voltage multiplier for a Marx generator, careful circuit design is essential to avoid inefficiencies.
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Will a generic dc motor interrupt the circuit fast enough to get a ac current on the other side of the transformer. I was assuming that a motor interrupt the flow of current.This is to feed a voltage multiplier.
 
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Are you thinking of putting a DC motor in series with the primary of a transformer?

This would not be a good idea because, at best, you would get pulsing DC current into the primary of the transformer and this would possibly saturate the core of the transformer.

Also, DC motors are designed so that they have very small gaps in the commutator, so there will be only very small interruptions to the supply of current to the transformer.

So, you might get very short pulses of voltage produce on the secondary, but it would be very inefficient.
 
That is what I was thinking. I will just use a self switched relay. Will this also saturate the core if so what is the best solution.
 
The best solution is to use transistors to do the switching.
Like this:
images?q=tbn:ANd9GcSNAWockavbyZZBf2O1T1DcrSDqD8rJqUIUYf1tOBBBB5kHa54a.png


Or see lots more circuits here:
http://www.google.com.au/search?tbm...rter+circuit&gbv=2&aq=1&aqi=g8&aql=&oq=DC+DC+

However, you can do it with a relay. You just need to reverse the direction of the current with each switching.

[PLAIN]http://dl.dropbox.com/u/4222062/Reversing%20switch%205.PNG

The relay would have to have two switches on it that are double pole double throw, as well as another contact that could be used to turn the relay coil on and off. This is not shown in the diagram.
 
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Thanks for the response. Was specifically trying to get like 300v to drive the voltage multiplier to drive the Marx generator. Although irritatingly he don't supply plans for his inverter.

http://www.instructables.com/id/Build-a-simple-Marx-Generator/


All my simple circuits come from a 3000 in 1 electronics kit from like 30 years ago that's where I got the chopper circuit.
 
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