High-frequency Harmonic Resonance Suppression In High-speed Railway Based On Single-phase Rectifier With An LCL Filter

High-frequency resonance is one of the urgent problems in the process of China high-speed railway operation, because of the lack of thorough and comprehensive awareness for traction power supply systems (TPSS) and high speed trains (HST). If the high-frequency resonance cannot be suppressed effectively, the normal operations work of TPSSs and HST will exist a security risk. Under the support of the National Natural Science Foundation "Modeling of dynamic and nonlinear high-speed train load and harmonic resonance suppression based on optimizing its characteristics (No.51207131)", this paper focuses on high-frequency resonance in high-speed railways, and the resonant suppression in the aspect of traction drive system. With the application of a single phase LCL rectifier in high-speed train, a high frequency resonance suppression scheme is proposed, which provides a new idea for harmonic resonance suppression. The main content of this paper is summarized as follows:Firstly, all-parallel autotransformer-fed TPSS and HST traction drive system are described. The modeling method of the TPSS’s circuit elements and the control strategy of PWM rectifier are introduced, respectively. A combined simulation system for the TPSS and the HST traction drive system is developed in Matlab/simulink software tool. Then the high-frequency resonance is simulated in the combined simulation system. And the simulation results verify the effectiveness of the simulation system.Secondly, the mechanism of high-frequency resonance is studied. A high-frequency resonance analysis model is established based on the single-line simplified model of traction network. And the relationship between the high-frequency harmonics of the power supply voltage and the line current of HST is indicated. On the basis of resonance analysis model, the resonant characteristics influenced by the LCL filter is shown. Furthermore, The theoretical analysis is effectively verified by simulation.Thirdly, focusing on the operation principle and control algorithm, single-phase LCL rectifier is studied, whose topological structure is introduced, and the mathmatical model is shown. The parameter desgn method of the LCL filter is discussed. According to the active damping algorithm widely adopted in three-phase system, the virtual-resistance and double band-pass-filter method is adopted in the single-phase LCL rectifier, and the instantaneous current control method and the active/reactive current decoupling control is discussed. The feasibility and effectiveness of the filter parameter design and the adopted control algorithms are verified by simulation in Malab/Simulink.Finally, A hardware-in-the-loop real-time simulation platform is developed with the RT-LAB and TMS320F2818DSP controller. The coupling modeling of traction power network and traction drive system in train is shown. And The control procedure of single-phase LCL rectifier is designed. The hardware-in-the-loop real-time simulation results verify the correctness of the control algorithm and the effectiveness of the high-frequency resonance suppression by using the LCL rectifier.