Brushless motor and electrical equipment

Abstract

The invention provides a brushless motor and electrical equipment, the brushless motor comprises a casing, a stator and a rotor, the stator comprises a stator iron core and a winding, the rotor comprises a rotor core and a rotating shaft, a bearing is sleeved on the rotating shaft, two ends of the casing are provided with bearing brackets respectively, each bearing bracket is insulated from the stator iron core, a conducting strip used for balancing the potentials of the bearing inner ring and the bearing outer ring in a matched mode is arranged between at least one bearing bracket and the stator iron core, and the conducting strip is electrically connected with the stator iron core and one adjacent bearing bracket. According to the brushless motor, the conducting strip is arranged betweenthe stator iron core and the bearing brackets, and the conducting strip is electrically connected with one of the stator iron core and the adjacent bearing bracket, so that the conducting strip is incapacitance connection with the stator iron core or the adjacent bearing bracket, the capacitive reactance between the stator iron core and the bearing bracket is adjusted, the potentials of the bearing outer ring and the bearing inner ring are balanced, the potentials of the bearing outer ring and the bearing inner ring are close, the shaft voltage is reduced, and the bearing is prevented from electric corrosion.

Description

technical field [0001] The invention belongs to the field of motors, and more specifically relates to a brushless motor and electrical equipment using the brushless motor. Background technique [0002] In recent years, due to the energy-saving trend of air-conditioning units, high-efficiency brushless DC motors have been used to drive fans instead of induction motors. These brushless DC motors are generally driven by an inverter, which uses a pulse width modulation (Pulse Width Modulation) method (hereinafter referred to as PWM) as a driving method. When using the PWM driving method, since the neutral point potential of the winding is not zero, a common-mode voltage will be generated; in the case of high frequency, coupling capacitance will be generated between the structures of the motor, and this common-mode voltage will pass through The coupling capacitance and bearing capacitance form a loop between the stator, rotor, rotor core, bearing bracket and other parts, which w...

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Problems solved by technology

[0003] The purpose of the embodiments of the present invention is to provide a brushless motor to solve the problem in the prior art that the shaft voltage of the brushless motor is too high and cause electric corrosion of the bearing

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