Poidas "Inverter Software Control" Topic.


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Warpspeed
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Joined: 09/08/2007
Location: Australia
Posts: 3267
Posted: 01:23pm 01 Dec 2019      

  Quote  I had been wondering if you might also need to monitor the ac output as a secondry control  ...  sort of a backup measure in case the output did get out of hand  ...

Not really, if its functioning properly it will work fine.  If something fails, all bets are off.
Even voltage feedback can fail open circuit, and the control system will then ramp up the output to absolute maximum.

If extreme output accuracy is a requirement, slow feedback could be added to a feedforward system, and is sometimes done. This could take the form of a slow self learning algorithm.

An example of that might be the engine management system in your car. The basic system uses many different engine sensors, rpm, load, temperature and so on fed into a series of lookup tables to create outputs for fuel delivery and ignition timing.
Its a very fast acting feed forward system. There is usually no feedback required for it to work.

However, there may be a lambda sensor in the exhaust that can be used to make very small changes to correct for engine wear or the gradual drift of engine sensor outputs over time. That is a form of very slow feedback which gradually modifies the much faster main feedforward control system.

  rogerdw said  
You probably need to delete all these posts in case the commercial boys read them and steal the idea.  
Cheers,  Roger

In a past life I used to work for both Invertech and Solar Basic as a power electronics design engineer, designing commercial inverters amongst many other things.

None of these ideas are new or revolutionary, and not patentable, its all a prior art.
All the control system concepts date back to about the 1930's and its all pretty well understood.

Its all jolly good fun and interesting, and in retirement if I can pass on a few tips and ideas that others find useful that is reward enough for me.
Edited 2019-12-01 23:59 by Warpspeed
Cheers, Tony.