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
Q. How does a MOSFET amplify electrical signals? While a minimum requirement for amplification of electrical signals is power gain, one finds that a device with both voltage an

For a discrete time unit step input x(kT), the output  y(kT) of a system is shown below,   Part (a)  Obtain the Z-transform of the output signal y(kT).   Part (b)   F

Difference between linear and non-linear resistors

Q. Explain working of three-phase transformers? Transformation in three-phase systems can be accomplished in either of two ways: (1) connecting three identical single-phase tra

Q. Why FET is called a voltage-controlled device? Why its input resistance is high? In the case of a FET the output current ID is a function of the voltage VGS applied to the i

Both DTL and TTL are based on the saturating BJT inverter. The transistor acts as a switch that connects or disconnects the collector and emitter. The switch is closed when suffici

Q. For a 10-bit R-2R ladder-network D/A converter with an MSB resistor value of 10 k, what is the value of the LSB resistor?

DI Disable  Interrupts Instruction The interrupt enable  flip flop is reset and all the  interrupts of 8085 microprocessors  except  TRAP  are disabled . the  instruction  form

If a high resolution emcoder is used for position control, will the number of pole count in the DC motor be matter? What is the requirement for the DC motor in order to work with h

I want proof of shockley diode equation with all steps