Why is efficiency greater at no load than full load for an induction motor?
Efficiency at no loadInduction motors have very low efficiency when operating without load. Specifically, the efficiency of an induction motor at no load is close to zero. This is because at no load, the motor does not carry an actual load, so the output mechanical power is very small. However, the motor still needs to consume energy to maintain its internal magnetic field and other necessary operations, and these energy losses are manifested as copper loss, iron loss, and mechanical loss, etc.