Switching characteristics - power semiconductor devices, Electrical Engineering

Switching characteristics

When  a positive signal  is applied GTO starts  conducting before  initiation of  conduction anode  current  is zero  and anode to cathode voltage Vak is the peak reverse voltage. When conduction starts anode  current  rises from  to full value  and the anode to cathode voltage Vak becomes very small when a negative gate signal is applied the anode current  becomes  zero and  the Vak  rises to peak revise voltage. The  total turn OFF  time can be  divided in three  distinct times storage time   fall time and tail time the switching characteristic of a FTO  is shown  in figure.

As soon  as negative gate  signal  is applied turn OFF  process starts  immediately. The  time  clasping between  application of  negative gate  current  till this current  reaches its  negative  peak value known  as storage time. During  this period the  excess charges are removed by the negative gate current and GTO gets ready to  turn OFF. During  fall time  tf the anode current decrease rapidly and anode to cathode voltage rises. This  time tf in most GTO  is about at  the end to tf the current falls  slowly to zero value during tail time  tf.  At  the end to the tail time  the anode current  Ia becomes  zero  and Vak  becomes  equal  to peak reverse voltage.

There  are many  advantages and disadvantage of GTO over thyristor some advantages of GTO  are as follows:

a.Commutation circuit is not  needed

b.Fast switching  speed

c.More di / dt at turn  ON

d.Higher efficiency because losses in commutations circuit is eliminated

e.Circuits using GTO  are compact

f.Lesser acoustical and electromagnetic noise  due to  elimination  of choke  of commutation

 

Posted Date: 4/2/2013 7:00:56 AM | Location : United States







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

Write discussion on Switching characteristics - power semiconductor devices
Your posts are moderated
Related Questions
Explain the 8259 microprocessor. 8259: The 8259A adds 8 vectored priority encoded interrupts to the microprocessor. This can be expanded to 64 interrupt requests with us

Hysteresis results in a dissipation of energy Hysteresis results in a dissipation of energy which appears as a heating of the magnetic material. The energy loss associated wit


Prepayment Meters Usage of prepayment meters will extensively improve the revenue collection of the utilities. There are a number of ways in that prepayment assures revenue pr

Q. Two balanced, three-phase, wye-connected loads are in parallel across a balanced three-phase supply. Load 1 draws a current of 20 A at 0.8 power factor leading, and load 2 draws


Define Sigma-Delta Analog to Digital Converters? Sigma-Delta ADCs have the benefit of being implemented almost totally in the digital domain.  They are extremely reliable, high

Explain the 16-bit registers DPTR and SP of 8051. DPTR: DPTR stands for data pointer. DPTR having of a high byte (DPH) and a low byte (DPL). Its function is to hold a 16-b

what are the types of binary codes

The relationship between cell and batteries  Generally, a cell delivers a certain voltage that is a function of what chemical reactions are taking place to generate the voltage