The torque of a reluctance motor can be effectively decreased bya)decr...
Torque developed in a reluctance motor is given by
Te ∝ (Rlq - Rld)
If Rlq/Rld is less, it means Rlq < RId and thus, Te is less.
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The torque of a reluctance motor can be effectively decreased bya)decr...
Torque of a reluctance motor is prop to ( 1/xq-1/xd) now , reactance , or lets say inductance is inversely prop to reluctance , thus 1/xq need to be less , means quadrature axis reluctance need to be less . hence Rq/Rd need to be less for reducing torque of a reluctance machine
The torque of a reluctance motor can be effectively decreased bya)decr...
Explanation:
To understand why the torque of a reluctance motor can be effectively decreased by decreasing the ratio of quadrature axis reluctance to direct axis reluctance, let's first understand the basic principle of operation of a reluctance motor.
A reluctance motor operates based on the principle of reluctance torque. It consists of a stator with windings and a rotor with salient poles. When the stator windings are energized, a magnetic field is produced, which interacts with the salient poles of the rotor. The rotor aligns itself with the stator field due to the principle of minimum reluctance.
Reluctance Torque:
Reluctance torque is generated due to the tendency of the rotor to align itself with the stator field. The magnitude of reluctance torque depends on the difference in reluctance along the direct axis (aligned with the stator field) and the quadrature axis (perpendicular to the stator field) of the rotor.
Effect of Reluctance Ratio:
The ratio of quadrature axis reluctance to direct axis reluctance plays a crucial role in determining the torque characteristics of the reluctance motor. Here's how each option affects the torque:
a) Decreasing reluctance of the magnetic circuit along the quadrature axis:
This option would increase the difference in reluctance between the direct and quadrature axes. As a result, the reluctance torque would increase, leading to an increase in the overall torque of the motor.
b) Increasing reluctance of the magnetic circuit along the direct axis:
This option would decrease the difference in reluctance between the direct and quadrature axes. As a result, the reluctance torque would decrease, leading to a decrease in the overall torque of the motor.
c) Increasing the ratio of quadrature axis reluctance to direct axis reluctance:
This option would increase the difference in reluctance between the direct and quadrature axes. As a result, the reluctance torque would increase, leading to an increase in the overall torque of the motor.
d) Decreasing the ratio of quadrature axis reluctance to direct axis reluctance:
This option would decrease the difference in reluctance between the direct and quadrature axes. As a result, the reluctance torque would decrease, leading to a decrease in the overall torque of the motor. This is the correct option.
Conclusion:
In summary, the torque of a reluctance motor can be effectively decreased by decreasing the ratio of quadrature axis reluctance to direct axis reluctance. This reduces the difference in reluctance between the two axes, resulting in a decrease in the reluctance torque and overall motor torque.
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