ECE :: Power Electronics
-
An SCR is triggered at 40° in the positive half cycle only. The average anode current is 50 A. If the firing angle is changed to 80°, the average anode current is likely to be
-
The characteristics of a non-linear resistance is i = kv4. If i becomes 100 times, v becomes
-
In a step down chopper using pulse width modulation, Ton = 3 x 10-3 and Toff = 1 x 10-3 s. The chopping frequency is
-
Assertion (A): Inverters and choppers use fast switching thyristors
Reason (R): Fast switching SCR has low turn off time.
-
The value of capacitor C for dynamic equalising circuit of series connected thyristors is determined by
-
A chopper
-
Assertion (A): If the duty cycle of chopper is low the current would not become discontinuous
Reason (R): If the time constant L/R of the load in chopper is low the current may become discontinuous.
-
In a single phase full wave regulator, the firing angles in the positive and negative half cycles are generally
-
An electric heater is controlled by thyristors through on-off control. If a = 0.4, the heating is
Whatsapp
Facebook
.
.