A Novel Power Quality Comprehensive Compensation System For High-speed Railway

High-speed electric railway is a special load to power grid due to the unique power supply mode and complicate operation condition. The electric locomotive brings in abundance harmonic current and negative sequence current to power grid. Harmonic current and negative sequence current will increase the system power lose and disturb nearby communication line.In some case, it may cause power system resonant and malfunction of protective relaying equipments.With the rapid construction speed of high-speed electric railway,the power quality becomes a big threat to the safety and reliable of power system. Therefore, Studying on the generating mechanism of electric railway power quality and corresponding control equipments becomes more and more important.Firstly, several usual AC electric railway power supply modes home and abroad and the corresponding merits and demerits of them are introduced.And the load characteristic of electric railway and several way of alleviating electric railway power quality problems were analyzed. Then,railway power conditioner (RPC), a great potential power energy conditioner for the electrified railway, is detailed analysed, including the operating principal and equivalent electrical model under V/v transformer.Secondly,a novel power quality compensation system consisted of RPC in parallel with Thyristor Switched Reactor (TSR)and Thyristor Switched Low-pass Filter(TSLF)is proposed on the basis of mature analysis of RPC. The topology, compensation principle and equivalent electrical model of the new system are emphatically analyzed. And its relative analysis with RPC on the active capacity is experimented under the platform MATLAB. Compared with single RPC, the novel system bears relatively less active capacity.Thirdly, the parameters design of main part of the novel system, including the Low-Pass Filter, Output Filter, DC side capacitance and the TSR are discussed. .Then, according to the actual operating condition, the novel system simulation mode is built in PSIM and several simulations are taken out. Results indicate that the principal of the novel system and the parameters design of the main circuit are valid.Finally, an experimental platform is set up to further validate the new system. In this section, the control part of the experimental platform, power module selection of the main circuit and IGBT driver and relevant protective circuit of them are detailed analysised. At last, a set of experiments are carried out, the experimental results verify the correctness and reliability of the research content.