Method and system for suppressing DC side voltage oscillation

Abstract

The invention discloses a method and system for suppressing DC side voltage oscillation, which is applied to an urban rail vehicle including a linear motor traction system, including: determining the voltage oscillation amount of the inverter DC side voltage; converting the voltage oscillation amount into a slip Frequency compensation, and compensated at the given slip frequency of the linear motor; calculate the stator frequency based on the compensated given slip frequency and the rotor frequency of the linear motor, and re-determine the synchronous rotation coordinates of the vector control system according to the stator frequency Transform the coordinate conversion angle value in the formula; use the re-determined vector control system to adjust the output of the inverter to suppress the amount of oscillation. This application compensates the given slip frequency and readjusts the output of the inverter, so that the linear motor consumes the voltage oscillating on the DC side of the inverter, so that it is not easy to cause the torque ripple of the linear motor, and it is not easy to trigger the traction system overshoot. Overvoltage and overcurrent fault protection improves the stability of the traction system and driving safety.

Description

technical field [0001] The invention relates to the technical field of oscillation suppression, in particular to a method and system for suppressing DC side voltage oscillation. Background technique [0002] At present, linear motor traction systems are widely used in urban rail vehicles due to their advantages such as strong climbing ability, small turning radius and low cost. Please refer to figure 1 , figure 1 It is a vector control schematic diagram of a linear motor traction system in the prior art. In the prior art, the linear motor traction system is powered by a DC power supply filtered by an LC filter circuit, and then the inverter outputs three-phase AC power to the three-phase symmetrical windings a, b, and c of the linear motor, wherein, The stability of the three-phase alternating current is based on the control of the vector control system. [0003] The specific control process of the vector control system includes: 1) collecting the three-phase AC current ...

AI Technical Summary

Problems solved by technology

[0004] However, the existence of the LC filter circuit easily causes the DC side voltage oscillation of the inverter, which in turn causes the torque ripple of the linear motor, which easily triggers the overvoltage and overcurrent fault protection of the traction system, affecting driving safety.

However, the existing vector control system only controls the output of the inverter to stabilize, and cannot consume the oscillating voltage on the DC side, and thus cannot suppress the oscillation of the DC side voltage.

Images