An active filter and a method for eliminating the secondary resonance of a train DC bus bar

Abstract

The invention discloses an active filter and a method for eliminating the secondary resonance of a train DC bus bar. The active filter comprises a bi-directional DC/DC converter with a step-up and step-down voltage function, a filter inductor and an energy storage capacitor. According to the principle of power balance, when the secondary ripple of bus voltage is fully compensated, the secondary ripple power of single-phase rectifier should be controlled equal to the secondary ripple power compensated by active power filter, and the direction is opposite. According to the voltage, current and other electrical quantities detected by the actual system, the closed-loop control is carried out, which ensures the compensation effect and the dynamic response ability of the system when the train isrunning, and improves the stability of the system. It can replace the traditional passive LC filter, can overcome the shortcoming that the passive filter can only compensate the harmonics of fixed frequency, can adapt to the complex power network environment, and the effect is more ideal than the traditional method. The device can reduce the volume and weight of the traction drive system, reducethe cost and increase the power density of the converter.

Description

technical field [0001] The invention relates to a rail transit single-phase power supply system, in particular to a vehicle-mounted traction converter AC-DC-AC system. Background technique [0002] Because of its simple structure, strong reliability, and high efficiency, single-phase converters are not only used in locomotive traction converter systems, but also in uninterruptible power supplies, photovoltaic grid-connected, cascaded multi-level converters, multi-phase AC drives, aviation It has been widely used in various power electronic systems such as aerospace power supplies. At present, most of the world's high-speed trains use modern AC drive systems. The AC-DC part of the traction drive system adopts single-phase PWM rectification with four-quadrant operation, which can feed back the energy of the locomotive during braking to the grid, and at the same time make the system have a higher efficiency. power factor. However, the single-phase system will generate inheren...

AI Technical Summary

Problems solved by technology

[0004] The present invention provides an active filter and a method for eliminating the secondary resonance of the train's DC bus to solve

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