Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Brushless DC electric motor
open-in-new
<p>A brushless DC electric motor (BLDC), also known as an electronically commutated motor, is a <a href="/facts/Synchronous_motor/s9y1U8J4">synchronous motor</a> using a <a href="/facts/Direct_current/r9MNUx84">direct current</a> (DC) <a href="/facts/Electric/hNC8D65W">electric</a> power supply. It uses an electronic <a href="/facts/Control_system/8CEjIDlS">controller</a> to switch DC currents to the motor <a href="/facts/Windings/fk2ElSDk">windings</a>, producing magnetic fields that effectively rotate in space and which the permanent magnet rotor follows. The controller adjusts the phase and amplitude of the current pulses that control the <a href="/facts/Speed/I3qgMPfs">speed</a> and <a href="/facts/Torque/KcrcvNtV">torque</a> of the motor. It is an improvement on the mechanical <a href="/facts/Commutator_(electric)/T89yIo7u">commutator</a> (brushes) used in many conventional electric motors. </p><p>The construction of a brushless motor system is typically similar to a <a href="/facts/Permanent_magnet_synchronous_motor/s9y1U8J4">permanent magnet synchronous motor</a> (PMSM), but can also be a <a href="/facts/Switched_reluctance_motor/WvIvSUV4">switched reluctance motor</a>, or an <a href="/facts/Induction_motor/DgTnMmJM">induction (asynchronous) motor</a>. They may also use <a href="/facts/Neodymium_magnets/1LApJ5Xq">neodymium magnets</a> and be <a href="/facts/Outrunner/QWmqtnIc">outrunners</a> (the <a href="/facts/Stator/pKBWvIHI">stator</a> is surrounded by the rotor), <a href="/facts/Inrunner/pVdajHzz">inrunners</a> (the rotor is surrounded by the stator), or <a href="/facts/Axial_flux_motor/JgwGTWVH">axial</a> (the rotor and stator are flat and parallel). </p><p>The advantages of a brushless motor over <a href="/facts/Brushed_motor/9429HDoK">brushed motors</a> are high power-to-weight ratio, high speed, nearly instantaneous control of speed (rpm) and torque, high efficiency, and low maintenance. Brushless motors find applications in such places as computer peripherals (disk drives, printers), hand-held power tools, and vehicles ranging from model aircraft to automobiles. In modern washing machines, brushless DC motors have allowed replacement of rubber belts and gearboxes by a direct-drive design. </p>