Static v- i characteristics - power semiconductor devices , Electrical Engineering

Static V- I Characteristics

A thyristor  works in  three basic  modes

a.Reverse  blocking mode

b.Forwards  blocking  mode and

c.Forward  conducting  mode

In reverse  blocking  mode cathode is made  positive  with respect to anode  and gate  circuit  remains  open as shown  in figure  in this  mode junctions  J1 and J3 are seen  to be reverse  biased and junction J2 is forward  biased. A very  small  current  flows.

1517_Characteristics.PNG

                             Figure(a) reverse blocking  mode (b)forwards blocking  mode  (c)forward  conducting mode

An avalanche breakdown  occurs  at junction J1 and J3. When  reverse voltage  is increased and  reverse  current  increase  rapidly  as shown in figur.

In forward  blocking  mode anode is positive  with respect to cathode and gate is  opened. Since  the junctions J1 and J3 are forward biased whereas junction J2 is reverse biased. Hence  a small  leakage current  flow  called forward  leakage  current. When  forward  voltage  is increased junction J2 will have  avalanche  breakdown  at a  voltage named forward  break over voltage  vBo.  

In  forward  conduction mode  anode  is made  positive with  respect to  cathode  and gate is  also made  positive with respect  to cathode. As positive  gate  voltage  is applied   between gate and  cathode at a particular  forward  anode  voltage junctions  J2 comes in  forwards bias  from reverse bias  condition and a  forwards anode  current flow  in the  circuit  with very small  voltage drop  across  the thyristor.

 

Posted Date: 4/2/2013 3:32:29 AM | Location : United States







Related Discussions:- Static v- i characteristics - power semiconductor devices , Assignment Help, Ask Question on Static v- i characteristics - power semiconductor devices , Get Answer, Expert's Help, Static v- i characteristics - power semiconductor devices Discussions

Write discussion on Static v- i characteristics - power semiconductor devices
Your posts are moderated
Related Questions
Explain SEGMENT assembler directive with example. SEGMENT: This directive described to the assembler the start of a segment along with name segment-name. The seg


Tick of the property, which is different from the group (A) Ductility.                (B) Resistivity. (C) Tensile strength.   (D) Hardness. Ans: Tick of the pr


Q. Define Resistance Strain Gauge? Mechanical and civil engineers routinely employ the dependence of resistance on the physical dimensions of a conductor to measure strain. A s

Measures of regulator quality: The output voltage can just be held roughly constant; the regulation is fixed by two measurements: 1. Load regulation is the alteration in ou

The input to the satellite system of Figure 1 is a step function θ c (t) = 5u(t) in degrees. As a result, the satellite angle θ(t) varies sinusoidally at a frequency of 10 cycles p

Electrical power Power P in an electrical circuit is given by the product of potential difference V and current I. The unit of power is the watt, W.

Buffer A buffer  is a logic circuit that  amplifies the current or power.  Basically it is used  change the driving  capability  of a logical  circuit. Therefore  it is  someti

Normal 0 false false false EN-IN X-NONE X-NONE RECTIFIERS AND INVERTERS