thyristorised dc drive

[jidiya]

@alertlink,
u have any report for ur prjct,
if yes can u send it???

 

[jidiya]

hi,,,,,,,i want to convert 10A to 0-5V,
what i have to do,??????
may be i have to convert 10a to 4-20ma and then 0-5 v using ic.
but first i need to convert it inn 4-20ma.
may be current transformer can do it bt i have to give specifiaction for design it and i don't know it.and may be it's costly
pls help!!!!!

 

[goldsmith]

Hi
You can use a differential amp that based on op amp and you will get sample from both side of sense current resistor , and this diff amp will have enough gain . and you can use a simple non inverting amp with op amp as second amplification stage .
Good luck
Goldsmith

 

[jidiya]

hi....is there any thyristorised h bridge available in market??????? i need it for .75hp-1 hp and 1a current rating.

 

[goldsmith]

Hi Again
I don't know is it available or no , but i'm sure that you'll be able to build one of them !
Good luck
Goldsmith

 

[jidiya]

hi guys can u exlpalian me how this circuit work....it's work great.
it's my main circuit of project.
irfz48-power mosfet
tlc250-power mosfet gate driver
1n400-diodes..
plz as soon as tell me... i need it very quikly

---------- Post added at 19:21 ---------- Previous post was at 19:20 ----------





hi guys can u exlpalian me how this circuit work....it's work great.
it's my main circuit of project.
irfz48-power mosfet
tlc250-power mosfet gate driver
1n400-diodes..
plz as soon as tell me... i need it very quikly

 

[wa1kij]

You say it works great. Does the output of the controller have any effect on the motor? Seems to me with D3 in the circuit, the motor would operate continuously.

 

[jidiya]

yes it work.....whatever rpm u want u get it...just set rpm and it is work

 

[dselec]

there is a problem with d3 its inverted
https://www.scribd.com/doc/63511583/3-Rc-Half-Full-Wave-Firing-Circuit-Rfc
this link show how to get full wave with scr

 

[wa1kij]

So the controller is getting information on how fast the motor is turning, and putting out pulses to control the speed.

 

[KerimF]

it's work great.

If the circuit (exactly as shown on post #26) can vary the motor speed, I think I have to consider revising all what I have studied, experimented and designed in the controller's electronics.

(1) The source is a high AC voltage (peak 325V) and the driver (IRFZ48) breakdown voltage is just 60V (Vdss). Fortunately it is shunted by D3 so Vds is at most close to about 1V only.

(2) The internal body diode of IRFZ48 allows current to pass in the other direction.

From (1) and (2), the circuit will work the same if IRFZ48 is shorted.


(3) I am not sure what will happen to IRFZ48 if the circuit runs in a real test. The voltage between its gate and source goes much beyond its limit +/- 20V.

In brief... I am not sure what Jidiya means by "It works great". I guess, he is the only one to know.

Kerim

 

[wa1kij]

Maybe between the half-wave rectifier and the choke in series with the FET the voltage is brought down to a reasonable level. Just a guess.

 

[KerimF]

Sorry... I am afraid I don't see an FET (or N-MOSFET) after being shorted by a diode and if not fried at its gate first.

 

[wa1kij]

I'm taking his word for it that it actually functions (but share your skepticism) and assuming D3 is connected the other way around.

 

[KerimF]

Ok... I agree with you on this point...
Now... Did you check the Vgs voltage assuming the MOSFET is on?

 

[wa1kij]

What exactly is the TLC2530? I haven't been able to find a datasheet for it. One search result comes up "optoisolator", though.

 

[KerimF]

On the schematic it looks, as you said, like the dual optocoupler MT25300.

In this case, the output pins 7 and 6 are open with respect to pin 5 (ground) or shorted to ground if enough current drives the input internal IR LEDs (pins 1/2 and pins 4/3) which can never happen in this circuit since pin 2 and pin 4 are unconnected

May I repeat what I have already said:

In brief... I am not sure what Jidiya means by "It works great". I guess, he is the only one to know.

Added:
There are other obvious wrong things on this circuit, so I prefer some others be in charge of it ;-)

 

[dselec]

tlc2530=hcpl2530
https://www.farnell.com/datasheets/87219.pdf
anyway where is jidaya ?
i am not going to take his word that his 60v fet with his dc motor and that stupid circuit with that stupid inverted d3 diode is working.
the most that can happen is he is shorting the half wave neg when input minus and when pos the fet internal zener is cutting away some pos voltage and his moter is running from max (if fet does not burn first the internal zener is protecting the fet)
useless to go on so lets wait for jidaya to read all our posts and prove us his circuit works.
once again a BIG BIG problem about this site filled with wrong circuits some people are surely burning some thing right now, i hope jidaya is ok.

 

[wa1kij]

Thank you for that datasheet. So he's supplying a 5V chip with 12V. Once the internal LEDs were lit, it would probably be the end of it. Just as well they're not grounded!

 

[dselec]

U r right that's why some times i get mad with these half backed cakes /circuits and by answering them we r responsible as well , because we dont get the whole picture and we still go on posting .
I feel like a teacher upset that his student is not doing well on and on so its a teachers dilemma should he give up or try and try again and again until the student gets it, and i personally would like to never give up.

---------- Post added at 12:07 ---------- Previous post was at 12:07 ----------

U r right that's why some times i get mad with these half backed cakes /circuits and by answering them we r responsible as well , because we dont get the whole picture and we still go on posting .
I feel like a teacher upset that his student is not doing well on and on so its a teachers dilemma should he give up or try and try again and again until the student gets it, and i personally would like to never give up.