Answer / ashraf majid

Thyristor convertor type AVR(Automatic Voltage Regulator)
is made of Thyristors(Silicon Controlled Rectifiers,SCRs).
We know that output DC voltage from an SCR will not only
depend upon the r.m.s. value of Input voltage applied, but
also at the angle at which the input AC cycle is fired
(using gate signal). If the firing angle is zero(in a
simple circuit), then maximum DC output voltage will be
obtained.If the firing angle is changed from 0 to 180,then
maximum to minimum voltage is obtained. This property could
be used to build an AVR. The firing angle proportional to
Output voltage could be used to trigger the thyristor,in a
closed loop manner and a nearly constant DC voltage(Average
Value) can be obtained.An invertor circuitory could be
utilised to get a regulated AC supply.
Many other configurations can be build from thyristors to
get a regulated AC supply.

what is meant by excitation current & armature current ? where its produce & how we can calculate ?

0 Answers  

---

The undesirable property of an electrical insulating material is

3 Answers  

---

1.what to do if ferquency of any power system continue to decrease ?

5 Answers   NTPC,

---

difference between earthing and grounding?

2 Answers   ABB, Bharti, L&T,

---

What is bode plot?

0 Answers  

---

why nearly all voltages are in the multiples of 11?

5 Answers  

---

Now I inject 1kv DC supply r&y=??? R&Y=?? Y&B=?? B&R=???? RYB&N=??? RYBN&E=????? Minimum value====???????

1 Answers   Integra,

---

Totally how much power will be consumed in 1 hour cotinuous running of electric train engine?

1 Answers   L&T,

---

If ac 230volts inputsupply to full wave rectifire what is D C output voltage.

3 Answers  

---

what are protective device needed to power a 360W ,50hz,240v,single phase,0.65 pf universal motor

1 Answers   L&T,

---

What is mean by hormonics?

5 Answers  

---

What's ND relay & it's functions?

2 Answers  

---