Power quality comprehensive control method and device for electric railway traction power supply system

Abstract

The invention relates to a power quality comprehensive control method and a power quality comprehensive control device for an electric railway traction power supply system, which belong to the field of electric railway power supply. The power quality comprehensive control device comprises a passive filter consisting of a trinary filter and a second-order high-pass filter and a set of voltage source converter with an energy-storage battery, wherein the voltage source converter with energy storage is connected with a 10kV bus in parallel through a phase reactor and the passive filter and then connected with a 110kV power network through a power transformer. The method and the device can compensate for power factors of the electric railway power supply system and solve the power quality problems of three-phase imbalance, harmonic wave, voltage fluctuation, flickering and the like at the same time. Moreover, the method and the device give full play to the advantages of simple configuration and low cost of the passive filter and the advantages of small occupied area and low loss of the voltage source converter, so that the whole device has the optimal technology index and economic performance.

Description

technical field [0001] The invention relates to a method and device for comprehensive control of power quality used in electric railway traction power supply systems, and in particular provides a method for reactive power compensation for electrified railways; active power control; negative sequence, harmonics, and voltage fluctuations The invention relates to a control device for comprehensive treatment of power quality such as flicker, belonging to the field of electrified railway power supply. Background technique [0002] The electric locomotive load in the electrified railway has the characteristics of nonlinearity, low power factor and three-phase imbalance, which not only seriously affects the power quality of the traction power supply system itself of the electrified railway, but also affects the power supply quality of the surrounding power users along the railway. Therefore, effective control measures must be taken for power quality problems such as negative sequen...

AI Technical Summary

Problems solved by technology

However, due to the randomness of the load of electrified railways, the compensation effect is not ideal, and the passive filter can only control the harmonics of a specific order, and has the disadvantage of easily resonating with the grid impedance to cause harmonic amplification

Active filters can dynamically suppress the harmonics of electrified railways, but cannot eliminate the negative sequence current in electrified railways

If SVC compensators such as TCR are used, the unbalance of the power supply system can be effectively improved and the negative sequence current can be reduced. However, TCR itself will generate a large number of harmonics during operation, and a large-capacity filter must be used to filter out the electric iron itself. harmonics and harmonics generated by TCR, the equipment occupies a large area and the corresponding investment is large

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