Speed Control Of DC motor using 3phase fully controlled bridge converter

[sina shekari]

Please I need help on speed control of 3phase motor using thyristor.
Whit these Descriptions:

Three Phase Fully Contolled Bridge Rectifier (6 Thyristors)
Change the firing angle using 6-pulse generator.
Voltmeter is used for measuring phase voltages.
Multimeter1 is used for measuring voltages across all the 6 thyristors.

 

[goldsmith]

Please I need help on speed control of 3phase motor using thyristor.
Whit these Descriptions:

Three Phase Fully Contolled Bridge Rectifier (6 Thyristors)
Change the firing angle using 6-pulse generator.
Voltmeter is used for measuring phase voltages.
Multimeter1 is used for measuring voltages across all the 6 thyristors.

Speed Control Of DC motor using 3phase fully controlled bridge converter

Hi Sina
First of all i need to say that name of your thread and the question which is inside are different . why ?
You said speed control of DC motor and then you have asked for a three phase motor control via thyristor !

I suspect it is some sort of final project isn't it ? and i hope you are not expecting that someone give you all of the things specially red paragraph in a map and you just build it !!!!

Anyway . i can guide you to design it . first mention the required power ( current and voltage ) and type of your nominal load . and ask what is your exact problem , then i'll guide you . furthermore , why SCR ? why not IGBT instead which can be much better here ?

Best Wishes
Goldsmith

 

[sina shekari]

i creat simulation but i don't know why my answers is not correct
speed image wave is not correct
i have attached my simulation

 

[BradtheRad]

Looking closely at the bottom-right terminals on T2, T4, T6...

They are connected to each other, but not to anything else.

You may have noticed already that if you try to ground those terminals, you get a short circuit.

 

[sina shekari]

Looking closely at the bottom-right terminals on T2, T4, T6...

They are connected to each other, but not to anything else.

You may have noticed already that if you try to ground those terminals, you get a short circuit.

i want to simulate shunt dc motor but i don't know how change the dc machine in matlab to shunt dc motor!!
i put ground as you told but the result didn't change!!

 

[BradtheRad]

This is the only arrangement which I can get to work with a 6 diode bridge (in simulation that is).



There is no short circuit (as shown by the scope traces). All six diodes get identical current.

It may not be easy to adapt thyristors to the above layout.

 

[sina shekari]

i think this site have lot of expert in power electronic but i find out most of them are amateur...
finally i myself find the problem and solve it.
some so-called expert thinking that it's my final project and i can not do it!