The correct answer is: A. Equivalent current method
The equivalent current method is the most accurate method for calculating the losses in a transformer. It is based on the principle that the losses in a transformer can be represented by an equivalent current that flows in the primary winding. The equivalent current is calculated by multiplying the rated current of the transformer by the square of the transformer’s efficiency.
The equivalent power method is less accurate than the equivalent current method. It is based on the principle that the losses in a transformer can be represented by an equivalent power that is dissipated in the transformer. The equivalent power is calculated by multiplying the rated power of the transformer by the square of the transformer’s efficiency.
The equivalent torque method is the least accurate method for calculating the losses in a transformer. It is based on the principle that the losses in a transformer can be represented by an equivalent torque that is applied to the transformer’s core. The equivalent torque is calculated by multiplying the rated torque of the transformer by the square of the transformer’s efficiency.
The method of average losses is a simplified method for calculating the losses in a transformer. It is based on the principle that the losses in a transformer can be represented by an average loss that is applied to the transformer’s windings. The average loss is calculated by dividing the total loss in the transformer by the number of windings in the transformer.
The equivalent current method is the most accurate method because it takes into account the actual current that flows in the transformer’s windings. The equivalent power method is less accurate because it does not take into account the actual current that flows in the transformer’s windings. The equivalent torque method is the least accurate because it does not take into account the actual current that flows in the transformer’s windings. The method of average losses is a simplified method that is not as accurate as the other methods.