Assertion (A): A fully controlled bridge converter can operate in fir...
Assertion (A): A fully controlled bridge converter can operate in first and fourth quadrant.
Reason (R): A semi converter is cheaper than a full converter.
Explanation:
To understand the given assertion and reason, let's first define what a fully controlled bridge converter and a semi converter are.
- Fully controlled bridge converter: It is a type of power electronic converter that uses thyristors to control the flow of current in both directions. It consists of four thyristors connected in a bridge configuration, allowing it to operate in both the first and fourth quadrants.
- Semi converter: It is a type of power electronic converter that uses only two thyristors to control the flow of current in one direction. It consists of one thyristor and one diode connected in a configuration that allows it to operate in either the first or the fourth quadrant, but not both.
Assertion (A): A fully controlled bridge converter can operate in first and fourth quadrant.
This assertion is correct. A fully controlled bridge converter can operate in both the first and fourth quadrants. In the first quadrant, the converter acts as a rectifier, converting AC input voltage to DC output voltage. In the fourth quadrant, the converter acts as an inverter, converting DC input voltage to AC output voltage.
Reason (R): A semi converter is cheaper than a full converter.
This reason is incorrect. A semi converter is not cheaper than a full converter. In fact, a fully controlled bridge converter is more expensive than a semi converter because it requires four thyristors, whereas a semi converter only requires two thyristors. The additional cost of the thyristors and the associated control circuitry makes the fully controlled bridge converter more expensive.
Conclusion:
Both Assertion (A) and Reason (R) are correct, but Reason (R) is not the correct explanation of Assertion (A). The operation of a fully controlled bridge converter in the first and fourth quadrants is not related to the cost of a semi converter.
Assertion (A): A fully controlled bridge converter can operate in fir...
Assertion (A): A fully controlled bridge converter can operate in first and fourth quadrant.
Reason (R): A semi converter is cheaper than a full converter.
The correct answer is option 'B'. Let's discuss the explanation for this answer in detail.
Explanation:
First and Fourth Quadrant Operation:
A fully controlled bridge converter is a type of power electronics converter that can operate in both the first and fourth quadrants of the voltage-current plane. In the first quadrant, both the input voltage and output voltage are positive, while in the fourth quadrant, the input voltage is negative and the output voltage is positive. This means that the converter can both step up and step down the voltage, allowing for bi-directional power flow.
Full Converter:
A fully controlled bridge converter consists of four thyristors connected in a bridge configuration. These thyristors can be turned on and off in a controlled manner using appropriate firing angles. By controlling the firing angles of the thyristors, the converter can control the power flow and voltage conversion.
Semi Converter:
On the other hand, a semi converter is a type of power electronics converter that consists of only two thyristors connected in a half-bridge configuration. This configuration allows for voltage conversion in only one direction, either from AC to DC or from DC to AC. The semi converter is simpler and cheaper compared to a full converter, but it can only operate in one quadrant (either the first or the fourth).
Correct Explanation:
The given reason (R) stating that a semi converter is cheaper than a full converter is not a correct explanation for the assertion (A) that a fully controlled bridge converter can operate in the first and fourth quadrant. The cost difference between a semi converter and a full converter is related to the complexity of the circuit and the number of components used, but it does not directly determine the quadrant of operation.
Conclusion:
In conclusion, a fully controlled bridge converter can operate in both the first and fourth quadrants, allowing for bi-directional power flow and voltage conversion. The assertion (A) is correct. However, the reason (R) given is not a correct explanation for the assertion. Therefore, option 'B' is the correct answer.
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