A 6-phase bridge-converter feeds a purely resistive load. The delay angle α is measured from the point of naturalcommutation. The effective control of voltage can be obtained when α lies in the range
Refer 12-pulse bridge converter which
would behave as 6-phase bridge converter
A 3-phase cycloconverter is used to obtain a variable frequency single-phase a.c. output. The single phase a.c. load is 220 V, 60 A at a power factor of 0.6 lagging. The rms value of input voltage per phase required is
In the below given circuit, the FD (Freewheeling diode) is forward biased at ωt =
It is forward biased at π by the conducting SCR & the current starts to through the FD & Load.
A d.c. source is switched in steps to synthesize the three-phase output. The basic three-phase bridge inverter can be controlled. The angle through which each switch conducts and at any instant the number of switches conducting simultaneously are, respectively
For a single-phase, full-bridge inverter supplying power to a highly inductive load as shown below, the correct sequence of operation of switches and diodes is
single-phase, half-bridge inverter has input voltage of 48 V DC. Inverter is feeding a load of 2.4Ω. The r.m.s. output voltage at fundamental frequency is
A boost-regulator has an input volage of 5V and the average utput voltage of 15V. The duty cycle is
Boost regulator is a step-up chopper
Which one of the following statements is The turn off times of converter grade SCRs are normally in the range of
Which one of the following statements is
A Triac is a
Which one of the following is correct?
In a switched capacitor network for VAR compensation the SCRs are commutated by
Which one of the following shows current fold back characteristics curve for a SCR controlled shunt regulated power supply?
Which one of the following statements is correct? In a transistor, the reverse saturation current ICO
Which one of the following statements is correct. In a thyristor, the holding current IH is
IL = 2 to 3 times IH
Which one of the following statements is correct ? For a SCR, dv/dt protection is achieved through the use of
In the buck-boost converter, what is the maximum value of the switch utilization - factor?
Which one of the following statements is correct?
In order to get best results per unit cost, the heat sinks on which the thyristors are mounted, are made of
Which one of the following is used as the main switching element in a switched mode power supply operating in 20 kHz to 100 kHz range?
MOSFET has lowest switching losses and
operates at high frequencies (~KHz range).
A converter which can operate both in 3-pulse and 6-pulse modes is a
A 3-phase semiconverter has the unique
feature of working as a six-pulse converter
for α < 60° and as a three-pulse converter
for α ≥ 60°.
A gate turn off (GTO) thyristor has capacity to
Match List-I (Limiting factor) with List-II (Safe Operating Area Portion) and select the correct answer using the codes given below the lists:
A. The peak voltage limit
B. Secondary breakdown limit
C. Power dissipation limit
D. Peak current limit