Industrial electronics: Unclear symbols

[Femme_physics]

Homework Statement

So in this circuit
http://img850.imageshack.us/img850/5061/circuittoregulate.jpg


Given that alpha = 60 degrees

I'm asked to draw qualitatively Vin, URL, UAK, and IAK.

Now Vin and URL are simple, but what ARE UAK and IAK? What are they? I don't see an "A" point on a circuit nor a "K" point

 

[Femme_physics]

Also I've turned this:

http://img708.imageshack.us/img708/2888/kkkkkkkkkkkkkw.jpg

Into this:

http://img35.imageshack.us/img35/1397/inhis.jpg And trying to solve a system of 3 equations but getting error in the calculator. So are my equations even correct? And is the way I redraw the circuit correct?

 

[I like Serena]

Hi Fp!

Don't you have a list of abbreviations in your course material?

Anyway, I've just looked it up.
See http://en.m.wikipedia.org/wiki/Thyristor
It has a pic showing the Anode and Cathode (aka Kathode).
That's your A and K of your Silicon Controlled Rectifier (SCR).

 

[I like Serena]

This is going to be soooooo messy with 3 problems in 1 thread.
I'm sure we will all be very confused very soon which problem/picture belongs to which post.
Can I suggest you make separate threads for them?

http://img35.imageshack.us/img35/1397/inhis.jpg


And trying to solve a system of 3 equations but getting error in the calculator. So are my equations even correct? And is the way I redraw the circuit correct?

Hmm, you removed the diodes. I guess that's ok as long as you keep careful track of the direction of the currents. As it is, I'm afraid you didn't. I3 can't flow the way you drew it.

Furthermore, you have drawn the 2 batteries in opposite directions, but that is never so.
You have 2 cases, but in each case the batteries must be in the same direction.

Finally, your 3rd equation is redundant. It is effectively contained in the first 2 equations.
That's the reason your calculator does not accept it.
You should add a KCL equation though...

 

[I like Serena]

Oh, the 3rd problem is a double-post...

 

[I like Serena]

As for the SCR problem, the element doesn't quite work like a regular diode.

Under normal circumstance it blocks in *both* directions.
It's only when a pulse is given on the "Gate" that current can flow through, in the regular direction of the diode, and then only as long as the voltage is up to keep it flowing.

When the voltage gets negative it blocks again in both directions.

 

[Femme_physics]

hehe...hey ILS!

Responding from your new offices at the dead sea? :D

Hi Fp!

Don't you have a list of abbreviations in your course material?

Anyway, I've just looked it up.
See http://en.m.wikipedia.org/wiki/Thyristor
It has a pic showing the Anode and Cathode (aka Kathode).
That's your A and K of your Silicon Controlled Rectifier (SCR).

Ah, you're right, I suppose this is exactly why they gave us alpha - the angle of ignition

As for the SCR problem, the element doesn't quite work like a regular diode.

Under normal circumstance it blocks in *both* directions.
It's only when a pulse is given on the "Gate" that current can flow through in the regular direction of a diode, and then only as long as the voltage is up to keep it flowing.

When the voltage gets negative it blocks again in both directions.

What do you mean by "pulse"?

And where is the gate? Is it the long horizontal line at the end of the triangle's tip?

Be back in 4-5 hrs

 

[I like Serena]

hehe...hey ILS!

Responding from your new offices at the dead sea? :D

Yep!
I've been swimming ON the water. It's never been so easy to do a crawl (as long as you keep you face well above the water - you really don't want water in your eyes!)

And what's really weird, is that there are lots of Dutch people here! :!)


And I've found a computer terminal at the reception, that makes this *a lot* easier.

Hi Fp!

Don't you have a list of abbreviations in your course material?

Anyway, I've just looked it up.
See http://en.m.wikipedia.org/wiki/Thyristor
It has a pic showing the Anode and Cathode (aka Kathode).
That's your A and K of your Silicon Controlled Rectifier (SCR).

Ah, you're right, I suppose this is exactly why they gave us alpha - the angle of ignition

Huh?
As yet this has nothing to do with alpha.

As for the SCR problem, the element doesn't quite work like a regular diode.

Under normal circumstance it blocks in *both* directions.
It's only when a pulse is given on the "Gate" that current can flow through in the regular direction of a diode, and then only as long as the voltage is up to keep it flowing.

When the voltage gets negative it blocks again in both directions.

What do you mean by "pulse"?

In this picture you can see how it behaves.
The bottom graph shows what a "pulse" looks like.

[URL]http://upload.wikimedia.org/wikipedia/commons/0/07/Regulated_rectifier.gif[/URL]

And where is the gate? Is it the long horizontal line at the end of the triangle's tip?

Yep, as you can see in this picture:
[URL]http://upload.wikimedia.org/wikipedia/commons/thumb/9/93/Thyristor_circuit_symbol.svg/200px-Thyristor_circuit_symbol.svg.png[/URL]

Be back in 4-5 hrs

Good that you mention that!

But... does that mean you want to do more work late in the evening?

 

[Femme_physics]

Yep, as you can see in this picture:

Got it :) ]

But... does that mean you want to do more work late in the evening?

Ended up falling asleep ^^

In this picture you can see how it behaves.
The bottom graph shows what a "pulse" looks like.

Oh right, where alpha is the ignition angle.

Yep!
I've been swimming ON the water. It's never been so easy to do a crawl (as long as you keep you face well above the water - you really don't want water in your eyes!)

And what's really weird, is that there are lots of Dutch people here!

hehe gOod to know

And I've found a computer terminal at the reception, that makes this *a lot* easier.

Good! and thanks.

About to leave for the test soon. thanks for everything!

 

[I like Serena]

Good luck!