Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Switching Characteristics During Turn off
The techniques used for turning off a thyristor is known as commutation techniques. A thyristor can be can be turn off by reducing the forward current to a level below the holding current IH.
The turn off time ( toff ) is time in which thyristor regain its forward blocking capability means thyristor changed its state form on state off state.
The turn off time t off is the sum of reverse recovery time Irr and recombination time trc. In t off time all the excess carriers must be removed from the four layers of SCR. After the forward current goes through the zero value, a reverse voltage appears across the thyrisotr as shown in figure1.12 this reverse voltage accelerants the turn off process by sweeping out the excess carriers from outer junctions J1 and J3,this is known as reverse recovery period and the time is reverse recovery time trr.
This reverse recovery time is shown in figure between time interval t1 and t3. The carriers around junction J2 and can be removed only by recombination because this junction is present between inner two layers. Actually after reverse recovery period junction J2 has trapped charges and these trapped charged cannot flow to the external circuit. Reverse voltage should be maintained across SCR for processing of recombination. Hence at the end of turn off a depletion layer develops across inner junction J2 and the thyristor recovers its ability to withstand forward voltages.
Figure Swithcing characteristics of SCR
Q. Define Power-Supply Rejection Ratio? An op amp's ability to disregard changes in power-supply voltage is measured by the power- supply rejection ratio (PSRR), which is speci
ON output plot of a JFET n-channel transistor if ID is close to IDSS does the value of VGS close to VP?
How to plot output power Vs load resistor graph using PSpice softwaer for half wave rectifier circuit
Question: (a) The piecewise linear approximation given in Figure is assumed for the diode in the circuit shown in Figure. Evaluate the diode current ID. (b) The piecew
1555_Use delta-wye transformation for network reduction.png what is the solution to this particular problem?
1. Frequency Modulation theory and its explanation 2. FM transmitter schematic, tests results and measurements 3. Amplifier and Oscillator circuit explanation and calculation
why h parameter used in low frequency transistor amplitfier
Data Copy Operations Instructions which are used to copy data from one location to another location kept in this category. The location from which data is copied is cal
transformation of independent variable e.g. time related explaination
Q. Explain Amplitude-shift keying? A carrier's amplitude is keyed between two levels (binary 1 and 0) in binary ASK. Figure shows the functions of a coherent ASK communication
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd