In an ac motor two components of energy are present. One component is the real power which is converted from electrical into mechanical energy and into heat in the form of motor losses. The second, reactive energy, is stored in the inductive elements of the machine. If a motor, or any ac circuit for that matter, has no capacitive or inductive elements, then all of the energy is expended as real power, but if either capacitance, inductance, or both are present, then some reactive energy will also be present. Electric motors contain inductive elements and, therefore, reactive energy is a consideration in selecting and applying motors in an energy-efficient manner.
KeywordsTorque Resis Sine Harness
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