Electric motors usually convert electrical energy into mechanical motion through the interaction of a magnetic field and a current-carrying conductor. Motors exist in many different applications, such as fans, blowers, pumps, machines, household appliances, power tools and disk drives. The largest motor rated at thousands of kilowatts is used in the propulsion of large ships and other applications. The smallest motor can move the dial in an electric watch.
The motor contains copper enameled wire to generate the desired magnetic field. For a given size frame, the high conductivity material reduces the energy loss due to coil resistance. Poor conductors produce more waste heat when they convert electrical energy into kinetic energy.
Due to its high conductivity, copper is commonly used for coil winding, bearing, collector, brush and motor connectors, including the highest quality motor. Copper has higher conductivity compared with other materials, which can improve the electric energy efficiency of the motor. For example, to reduce the load loss of continuous induction motors over 1 HP, manufacturers always use copper as the conductive material in the windings. Aluminum is a substitute for motors with smaller horsepower, especially when used discontinuously.
One of the design elements of a quality motor is to reduce heat loss due to conductor resistance. In order to improve the power efficiency of induction motor, the load loss can be reduced by increasing the cross section of copper coil. The amount of copper in stator winding is 20% higher than that in standard winding.
The early development of motor efficiency focuses on reducing electrical losses by increasing the filling weight of stator windings. This makes sense because electricity losses typically account for more than half of all energy losses, and stator losses account for about two-thirds of electricity losses. However, there are disadvantages in improving the electric efficiency of the motor through large Enameled Wire . This increases the size and cost of the motor, which may not be desirable in applications such as appliances and cars.