High-speed railway electric energy quality and traction network voltage comprehensive compensation system

Abstract

The invention provides a high-speed railway electric energy quality and traction network voltage comprehensive compensation system. The comprehensive compensation system comprises a single-phase back-to-back STATCOM installed on the traction side of a traction substation and thyristor switched high-pass filters installed in section posts. The single-phase back-to-back STATCOM is used for negative sequence compensation, lower-order harmonic filtration within the range of 2-11 order and power factor and traction network bus voltage control. The thyristor switched high-pass filters are used for absorbing high-order harmonic with the order of 11 or above and stabilizing the traction network terminal voltage. The single-phase back-to-back STATCOM can detect the power factor of the traction substation in real time, carry out dynamic stepless regulation on reactive output and maintain the power factor of the system to be 0.9 or above. The thyristor switched high-pass filters arranged in the section posts are used for absorbing harmonic currents with the order of 11 or above and improving the traction network voltage. The whole high-speed railway electric energy quality and traction network voltage comprehensive compensation system has the advantages of being small in occupies area, low in operation loss, low in construction cost, high in reliability, simple in technology implementation, prominent in comprehensive benefit and the like.

Description

technical field [0001] The invention relates to a system in the field of high-speed railway traction power supply, power electronics technology and power quality control, in particular to a comprehensive compensation system for high-speed railway power quality and traction network voltage. Background technique [0002] High-speed railways are valued by countries all over the world and are developing very rapidly due to their advantages such as fast running speed, large transport volume, energy saving and environmental protection, safety and comfort, and outstanding comprehensive benefits. At present, the operating mileage of my country's high-speed railway has exceeded 10,000 kilometers, ranking first in the world. According to the plan, by 2020, 16,000 kilometers of high-speed passenger dedicated lines with a speed of 200 kilometers per hour and above will be built. [0003] All high-speed railways use electric traction, and most of the traction substations that supply pow...

AI Technical Summary

Problems solved by technology

Limited by the switching frequency of the device, the RPC device can only compensate the low-order harmonic current limitedly, but cannot compensate for the high-order harmonic

[0007] Due to the wide spectrum of harmonic current in traction loads of high-speed railways, it is necessary to set up multiple LC passive filter branches when using FC or SVC devices for harmonic control, and the fundamental capacitive reactive current inevitably flows through the filter. For each branch, due to the high power factor of the high-speed EMU under various working conditions, the redundant capacitive reactive power is unnecessary, but the capacity and loss of the device will increase. Adding a thyristor phase-controlled reactor branch to the whole device will resulting in bulky devices and additional harmonic current sources

In addition, from the current operation diagram of high-speed railways, it can be seen that the effective operation time of each high-speed railway line is generally from 6:00 a.m. to 24:00 p.m., and other periods are outage periods. During this period, compensation devices do not need to play a role, while FC or SVC is a continuous operation device, which not only increases the equipment loss, but also further reduces the average power factor of the traction substation, increasing the operating cost

[0008] STATCOM realizes dynamic, real-time and fast continuous compensation of negative sequence and reactive power, while stabilizing the traction bus voltage, it can also realize active filtering function, which is suitable for fast reactive power, negative sequence and harmonic compensation of high-speed railway traction loads ; Due to the high voltage level and large compensation capacity of the STATCOM device used in high-speed railway power quality control, the switching frequency of the high-power switching device cannot be too high due to factors such as the loss of the switching device and the heat dissipation of the device. In practical applications, it is mainly used for 2 ~11th order harmonic current treatment, but cannot effectively compensate for high order harmonics

Images