A three-phase AC motor drive system that suppresses common-mode noise

Abstract

The invention discloses a three-phase AC motor drive system for suppressing common mode noise, which includes two sets of three-phase inverters, an additional load circuit, a drive control circuit, a sampling feedback circuit, two additional parallel bridge arms and corresponding coupled inductance. Based on the control system, the present invention provides a common-mode noise suppression method, which reduces the common-mode current and electromagnetic interference noise generated when the general inverter drives the motor under the condition of realizing the maximum utilization rate of the DC bus voltage, and suppresses its impact on The problem of continuous damage to components such as motor insulation and bearings, thereby solving the technical problem of common-mode noise of inverter-driven three-phase AC motors. The invention can select small-capacity and low-cost switching tubes to form an additional bridge arm, and can achieve the beneficial effects of reducing common-mode current and suppressing common-mode noise, protecting motor windings and bearing insulation, and improving system reliability.

Description

technical field [0001] The invention belongs to the field of AC motors and drive control, and more specifically relates to a three-phase AC motor drive system capable of suppressing common-mode noise. Background technique [0002] With the development of modern motor and power electronic control technology, AC motor frequency conversion speed regulation system driven by power electronic inverter has been widely used in the field of servo and traffic traction. Because the system's frequency conversion and speed regulation function is realized by pulse width modulation technology combined with the high-speed switching characteristics of the inverter, there is a common-mode voltage characterized by high-frequency pulse sequences at the winding end of the motor. The common-mode current generated by the common-mode voltage is conducted along the motor winding, and is conducted to the ground terminal through the stray capacitance between the motor winding and the casing or the bea...

AI Technical Summary

Problems solved by technology

[0003] Aiming at the above defects or improvement needs of the prior art, the present invention provides a three-phase AC motor drive system that suppresses common-mode noise. The common-mode current and electromagnetic interference noise generated when the inverter drives the motor suppresses the problem of continuous damage to the motor insulation and bearings, thereby solving the technical problem of the common-mode noise of the three-phase AC motor driven by the inverter

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