Micro controllers used in UPS systems

Hi all,

I would like to know what are the micro controllers used in high power UPS (50kVA or more) .

Thanks

Any...
Of course the micro controller (or any other logic for that matter) will have to be very strongly decoupled from the high voltage section of the design.

For that amount of power, I would not consider necessarily some DSP, but at least some core with similar performance, which would be able to make a lot of calculations involving not only root square functions, but also division and more.

Hi,

It seems some think that a 50kVA UPS needs more processing power than a 0.25kVA UPS.
I can't see why.

Our company builds control electronics for 8kVA ... up to 3MVA .. they all need about the same processing power.

Klaus

About the only thing that will change from a 0.5KVA UPS to a 50KVA one, is the level of monitoring and protection circuits.

Also...a larger UPS, costs lots more money. Therefore it may be cost-effective to provide a nice display which provides more and improved information with better graphics. Also implementing remote monitoring and control, adding more diagnostic data....that kind of stuff.

That would require a more capable processor, or even better, a dedicated processor just to handle all the "bells and whistles".

Hi KlauST

Thanks for the reply. But is there any specific info available say microcontrollers from Texas instruments/ Microchip etc used in commercially available UPS by companies say Schneider/Eaton etc.

Microchip 33EP series controllers are very useful for power applications. Those are high speed and with very advanced PWM features.

Hi,

Schmitt trigger is correct.

In our applications we don't have a display, all data are transferred with profibus.

And while we often use Atmel AVR type microcontrollers, I don't recommend them for your application because of limited processing power, ressources like memory and limited interface capabilities. Maybe an ARM based microcontroller is more suitable, or a DSP.

Our microcontrollers are supported by CPLDs or FPGAs. I personally like the idea of doing thos (safety) critical tasks in an FPGA rather than by software. I think a software is more likely to fail than an FPGA program. But indeed I never saw our microcontrollers to fail this way. A good PCB layout, shielding, filters on all IOs are mandatory.

We prefer the data communication via POF (plastic optical fiber) because of it's immunity against electromagnetical interference.
(We control up to 2500V and up to 6000A RMS, causing a lot of interference)

Klaus