Effect of filter and compensation unit in the traction power supply at extreme distortion

Abstract

The presented paper deals with the associated problems that come up with common installation of filter and compensation unit with decompensation reactor used in traction power supply system. The influence of single-phase traction converter on the traction trolley and load is a specific problem. The locomotives on the line are a source of harmonic currents. This source affects the voltage distortion on the system. Connection of filtration compensation unit significantly sinks the voltage curve distortion, especially at the power supply station. Due to compensation power of filters is necessary present decompensation reactor. This paper describes the steady states and is focused on the possible extreme cases. The influence of filter parameters in cases of extreme distortion has been investigated.

A novel locomotive auxiliary converter control strategy with harmonic suppression for avoiding resonance voltage accidents in an electrified railway

“…As for measures to suppress the harmonics, first of all, we can reconstruct traction substation, such as installing passive or active filters. The passive filter methods like installing a inductance and capacity filter or a high pass filter at traction substation can filter specific harmonics, but are unable to compensate the harmonic current dynamically when frequency changes . Based on power electronic technology, we can also install active power filter equipment along with a step‐down transformer to realize the dynamic compensation of harmonic current , such as the method of using two ‘back to back’ single‐phase full bridge converters and a power quality compensation system composed of a three‐phase voltage source converter and a thyristor switching capacitor.…”