Creating a virtual circuit with LabVIEW

[Terreh]

Hello,

I am first year engineering student on a summer vacation research program. Literally just started using LabVIEW.

My query - Can I create a virtual circuit then use LabVIEW to control switches/relays/circuit breakers within the circuit. My university has a microgrid and my research task over the holidays is to make an interface for this grid. The primary objective is to control switches etc. using LabVIEW. And hence being a first year student with plenty of prejudice against me (haha) it would be nice to use something virtual rather than something I could break.

Cheers

[CoastalMaineBird]

I'm not sure what you mean by "virtual circuit", or by "microgrid".

LabVIEW creates "Virtual Instruments"  (V.I.E.W. = Virtual Instrument Engineering Workshop).

You can have on-screen toggle switches, knobs, LED lights, tank-full indicators, right out of the box.

With a little bit of work, you can show a relay (need "open" and "closed" pics).

With a bit more work you can make it behave as a relay would.

With a hardware interface, you can use it to control real relays, lights, whatever.

That's what it's for.

[Terreh]

Ok this is my own understanding of the 'microgrid' (basically).

The microgrid has multiple buses  where on each bus there may be a load and/or a supply attached. between each bus there are switches/relays/circuit brakers/current transformers/inverters etc etc and things that purposely create faults to simulate issues that a real grid may experience. power supplies include pv's, diesel gens, hydro cells, wind gen (simulated), battery cells and of course it connect to mains. where it can import/export power to the grid.

basically the microgrid simulates a real power grid. its been built for phd students and undergrads.

i don't know how to explain virtual circuit.. it not physical. instead its a circuit you make and use on your comp?

[CoastalMaineBird · Accepted solution]

Then you have to figure out what you want to do.

If you want to simulate the whole shebang, you can do that.

You can simulate buses, with loads and supplies and switches and faults.  That's just mathematical operations.

After 37 seconds, the transformer at node 6-G fails and draws excessive current, does the breaker for bus 6 break the circuit OK?

I don't see what good that would do, but you could do it.

If you want to actually control the physical microgrid, then you have to have interface hardware.

Maybe you need a digital I/O board, where bit 0 turns on the supply to bus #6 and bit 1 turns on the load, and bit #2 turns on the over-current load, and you sense whether the breaker tripped by looking at bit 8, and so on.

Maybe you need some analog output, where you set the supply voltage to 130 V, and set the frequency to 65 Hz, instead of 60.

Maybe you need some analog input, where you measure the current at the point the breaker tripped, and measure the battery voltage, and so on.

There are MIO devices with some of all those domains, there are specialty devices concentrating on high performance in one of those domains.

LabVIEW can control them all. 

It won't be a cakewalk.  You cannot plug in the board, run LabVIEW and have it do what you want. You need to do some programming. It's a lot easier than using other languages, but it's not trivial.

Hope that helps.

[Terreh]

Thank you for the insight

[yenknip]

In your first post, you say that you want to make an interface for the mini power grid. Will this interface be controlling the physical hardware, or is the entire project a software simulation project? The hardware implementation will need a DAQ device. For circuit simulation, you will want to use circuit simulation software; SPICE, CircuitLab, Multisim, Croc Clips and so on.

[Terreh]

I want to simulate it via software first then implement it

to control hardware on the grid.