Transistor vs Thyristor

[boro3]

Hey Guys,
I have a question

its abou an npn Transistor in common emitter circuit and pnpn Thyristor.


Transistor Thyristor


P
___________________________________________
N N
P ----B P---G
N N
My question is why is it possible to trigger the thyristor but not the transistor.The transistor needs always an Basis current to get the Collector Current.flow

Thyristor: Trough an positiv Gate-Kathode Volatge the electrons from the N-Kathode Region can get to the P-Gate Region.
For a positive Volatge from Anode to Kathode, the electrons, from N Kathode Region wich got to P-Gate Region will flow further to P-Anode Region.
Then you can turn off the Gate signal an the current will flow further.
#
Transistor: I mean it schould be the same. trough an Basis-Emmiter Voltage, the Electrons from the N-Emitter Region can get to P-Basis Region.
For a positiv Volatge from Collector to Emitter, the electron will flow further to the collector.

So why it doesn function here to turn the Basis off?
What does the P-Anode of the Thyristor do what de Transistor dont have?
can you maybe explain it with the movement of electronen an holes?

Thank youuu

 

[Nigel Goodwin]

You're over thinking it - the thryistor is essentially just an NPN and a PNP transistor, connected so they hold each other ON even after the external trigger is removed. To reset it (as it's a latching circuit) you need to reduce the current through it to zero.