This set of FACTS Multiple Choice Questions & Answers (MCQs) focuses on “Power Semiconductor Devices – Current Sourced Converter – Set 3”.
1. A diode based CSC exhibits self commutation.
a) True
b) False
View Answer
Explanation: A diode based CSC does not exhibit self commutation. This is because it has no thyristors incorporated in it. Self commutation is achieved by gate turn-off devices.
2. A diode based CSC can ________
a) can control and can supply power
b) cannot control and can supply power
c) cannot control and cannot supply power
d) can control and cannot supply power
View Answer
Explanation: A diode based CSC cannot control and cannot supply power. It just converts ac power to dc power but has no control on this. It also consumes reactive power on its ac side.
3. A CSC can be constructed as a diode biased converter only.
a) True
b) False
View Answer
Explanation: A CSC can be constructed as a diode biased converter also. It can also be designed as a line commutated converter. It may also be a self-commutated converter.
4. A line commutated current source converter utilizes ________ for its construction.
a) diode
b) conventional thyristor
c) gate turn-off device
d) GTO
View Answer
Explanation: A line commutated current source converter utilizes conventional thyristor for its construction. It includes no diodes. Also gate turn-off devices are not present in line commutated current source converters.
5. A self commutated current source converter utilizes ________ for its construction.
a) diode
b) conventional thyristor
c) gate turn-off device
d) GTO
View Answer
Explanation: A self commutated current source converter utilizes gate turn-off devices for its construction. It includes no diodes. Also conventional thyristors are not present in line commutated current source converters.
7. Only GTOs but no IGBTs can be used for designing a self commutated current source converter.
a) True
b) False
View Answer
Explanation: Both GTOs and IGBTs can be used for designing a self commutated current source converter. Both GTOs and IGBTs are gate turn-off devices which can be the constituents of a self commutated converter. Here the turn off action of the device brings in the commutation of current from the valve to valve as required.
8. A line commutated CSC can ________
a) can control and can supply power
b) cannot control and can supply power
c) cannot control and cannot supply power
d) can control and cannot supply power
View Answer
Explanation: A line commutated CSC can control and cannot supply power. It can both convert and control active power in either direction. It also consumes reactive power on its ac side.
9. A self commutated CSC can ________
a) can control and can supply power
b) cannot control and can supply power
c) cannot control and cannot supply power
d) can control and cannot supply power
View Answer
Explanation: A self commutated CSC can control and can supply power. It can control active power in either direction. It also supplies or consumes reactive power as required.
10. CSCs based on conventional thyristors, utilize ac current from the system for commutation of current from one valve to another.
a) True
b) False
View Answer
Explanation: CSCs based on conventional thyristors, DO NOT utilize ac current from the system for commutation of current from one valve to another. They use ac voltage from the system for commutation of current from one valve to another. CSCs based on conventional thyristors lack in gate turn-off devices and hence cannot employ the turning-off action for commutation.
Sanfoundry Global Education & Learning Series – Flexible AC Transmission System (FACTS).
To practice all areas of Flexible AC Transmission System (FACTS), here is complete set of 1000+ Multiple Choice Questions and Answers.