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is the resistive power loss (SI unit: watt) The motor constant is winding independent (as long as the same conductive material is used for wires); e.g., winding a motor with 6 turns with 2 parallel wires instead of 12 turns single wire will double the velocity constant, , but remains unchanged.
In an electrical or electronic circuit or power system part of the energy in play is dissipated by unwanted effects, including energy lost by unwanted heating of resistive components (electricity is also used for the intention of heating, which is not a loss), the effect of parasitic elements (resistance, capacitance, and inductance), skin effect, losses in the windings and cores of ...
However, resistor losses associated with low speed operation of WRIMs is a major cost disadvantage, especially for constant loads. [40] Large slip ring motor drives, termed slip energy recovery systems, some still in use, recover energy from the rotor circuit, rectify it, and return it to the power system using a VFD.
Motor losses are mainly due to resistive losses in windings, core losses and mechanical losses in bearings, and aerodynamic losses, particularly where cooling fans are present, also occur. Losses also occur in commutation, mechanical commutators spark; electronic commutators and also dissipate heat.
In the DC injection method DC current is injected to the motor so that control of the motor flux is lost during braking. The flux braking method based on DTC enables the motor to shift quickly from braking to motoring power when requested. In flux braking the increased current means increased losses inside the motor.
A brushed DC electric motor is an internally commutated electric motor designed to be run from a direct current power source and utilizing an electric brush for contact. Brushed motors were the first commercially important application of electric power to driving mechanical energy, and DC distribution systems were used for more than 100 years ...
Copper loss is the term often given to heat produced by electrical currents in the conductors of transformer windings, or other electrical devices. Copper losses are an undesirable transfer of energy , as are core losses , which result from induced currents in adjacent components.
Windage loss is the reduction in efficiency due to windage forces. For example, electric motors are affected by friction between the rotor and air. [1] Large alternators have significant losses due to windage. To reduce losses, hydrogen gas may be used, since it is less dense. [2] There are two causes of windage: