】 motor ontology is usually composed of permanent magnet synchronous motor controller. The rotor adopts permanent magnet excitation. Because different geometric shapes of the rotor magnetic field, the rotor magnetic field distribution in the space of two kinds of sine wave and trapezoidal wave. For sine wave brushless dc motor controller, hope in winding sine wave form of voltage, its winding form using short, distribution, or fraction, to weaken the other harmonics as far as possible, so as to keep the base wave. 8 and square-wave brushless dc motor controller in order to get to 120 degrees of square wave or trapezoidal wave, stator winding in the form of the whole distance, focus, to retain flux density in the other harmonic. Motor noumenon must meet the requirements of electromagnetic aspect, first ensure that the work to produce enough in the air gap magnetic flux, the armature winding is allowed by a certain current, so as to produce certain electromagnetic torque; Second to meet the requirements of mechanical aspects, ensure mechanical mechanism is firm and stable, can transmit a certain torque, and can withstand the test of a certain environmental conditions.
