An Improved Droop Control Strategy for VSC-Based MVDC Traction Power Supply System

Due to the development of advanced power electronic techniques, voltage-source-converter-based medium voltage dc (MVDC) traction power supply system (VSC-based MVDC TPSS) could be an alternative supply solution for high-speed railways (HSRs) in the future. The distributed configuration of the MVDC system, along with dynamic load and catenary resistance, makes the control of such system a real challenge. In this paper, an improved droop control method is proposed to obtain a better performance of system operation for the specific supply environment without any communication links. The proposed control scheme can eliminate the voltage deviation due to droop action and improve catenary network voltage control dynamics by using voltage-shifting and load current feedforward control approaches simultaneously. Additionally, the detailed model of the proposed control scheme is derived and the stability in the case of moving load is critically tested. Finally, a simulation model based on MATLAB/Simulink and an experimental prototype have been established to validate the effectiveness of the proposed control method.

[1]  Guangfu Tang,et al.  New technologies of voltage source converter (VSC) for HVDC transmission system based on VSC , 2008, 2008 IEEE Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century.

[2]  Ke Wang,et al.  Power-Quality Impact Assessment for High-Speed Railway Associated With High-Speed Trains Using Train Timetable—Part I: Methodology and Modeling , 2016, IEEE Transactions on Power Delivery.

[3]  Zhengyou He,et al.  Train–Network Interactions and Stability Evaluation in High-Speed Railways–Part I: Phenomena and Modeling , 2018, IEEE Transactions on Power Electronics.

[4]  Juan C. Vasquez,et al.  An Improved Droop Control Method for DC Microgrids Based on Low Bandwidth Communication With DC Bus Voltage Restoration and Enhanced Current Sharing Accuracy , 2014, IEEE Transactions on Power Electronics.

[5]  Juan C. Vasquez,et al.  DC Microgrids—Part II: A Review of Power Architectures, Applications, and Standardization Issues , 2016, IEEE Transactions on Power Electronics.

[6]  H. Akagi,et al.  An approach to regulating the DC-link voltage of a voltage-source BTB system during power line faults , 2003, 38th IAS Annual Meeting on Conference Record of the Industry Applications Conference, 2003..

[7]  S. Bhattacharya,et al.  Vector-Controlled Voltage-Source-Converter-Based Transmission Under Grid Disturbances , 2013, IEEE Transactions on Power Electronics.

[8]  Juan C. Vasquez,et al.  DC Microgrids—Part I: A Review of Control Strategies and Stabilization Techniques , 2016, IEEE Transactions on Power Electronics.

[9]  Juan C. Vasquez,et al.  Hierarchical Control of Droop-Controlled AC and DC Microgrids—A General Approach Toward Standardization , 2009, IEEE Transactions on Industrial Electronics.

[10]  Fei Gao,et al.  An Improved Voltage Compensation Approach in a Droop-Controlled DC Power System for the More Electric Aircraft , 2016, IEEE Transactions on Power Electronics.

[11]  Liangzhong Yao,et al.  Integrating Wind Farm to the Grid Using Hybrid Multiterminal HVDC Technology , 2011, IEEE Transactions on Industry Applications.

[12]  Tsai-Fu Wu,et al.  3C strategy for inverters in parallel operation achieving an equal current distribution , 2000, IEEE Trans. Ind. Electron..

[13]  Fang Zheng Peng,et al.  Multilevel inverters: a survey of topologies, controls, and applications , 2002, IEEE Trans. Ind. Electron..

[14]  Bin Wu,et al.  Multilevel Voltage-Source-Converter Topologies for Industrial Medium-Voltage Drives , 2007, IEEE Transactions on Industrial Electronics.

[15]  Frank L. Lewis,et al.  Distributed adaptive droop control for DC distribution systems , 2016 .

[16]  Zhengyou He,et al.  Power quality in high-speed railway systems , 2016 .

[17]  A. M. Gole,et al.  The use of averaged-value model of modular multilevel converter in DC grid , 2015, 2015 IEEE Power & Energy Society General Meeting.

[18]  Flavio Ciccarelli,et al.  Line-Voltage Control Based on Wayside Energy Storage Systems for Tramway Networks , 2016, IEEE Transactions on Power Electronics.

[19]  Dianguo Xu,et al.  An Improved Distributed Secondary Control Method for DC Microgrids With Enhanced Dynamic Current Sharing Performance , 2016, IEEE Transactions on Power Electronics.

[20]  Juan Manuel Mauricio,et al.  VSC-Based MVDC Railway Electrification System , 2014, IEEE Transactions on Power Delivery.

[21]  Juan C. Vasquez,et al.  Tertiary and Secondary Control Levels for Efficiency Optimization and System Damping in Droop Controlled DC–DC Converters , 2015, IEEE Transactions on Smart Grid.

[22]  Mehdi Savaghebi,et al.  Flexible System Integration and Advanced Hierarchical Control Architectures in the Microgrid Research Laboratory of Aalborg University , 2016, IEEE Transactions on Industry Applications.

[23]  Li Guo,et al.  A Nonlinear-Disturbance-Observer-Based DC-Bus Voltage Control for a Hybrid AC/DC Microgrid , 2013, IEEE Transactions on Power Electronics.

[24]  T. Noguchi,et al.  Voltage-Source PWM Rectifier–Inverter Based on Direct Power Control and Its Operation Characteristics , 2011, IEEE Transactions on Power Electronics.

[25]  Hui Li,et al.  An Improved Control Strategy of Limiting the DC-Link Voltage Fluctuation for a Doubly Fed Induction Wind Generator , 2008, IEEE Transactions on Power Electronics.

[26]  M. Liserre,et al.  Design and control of a three-phase active rectifier under non-ideal operating conditions , 2002, Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344).

[27]  V.G. Agelidis,et al.  VSC-Based HVDC Power Transmission Systems: An Overview , 2009, IEEE Transactions on Power Electronics.

[28]  Sheng Liu,et al.  Electromechanical Transient Modeling of Modular Multilevel Converter Based Multi-Terminal HVDC Systems , 2014, IEEE Transactions on Power Systems.

[29]  J. Peralta,et al.  Detailed and Averaged Models for a 401-Level MMC–HVDC System , 2012, IEEE Transactions on Power Delivery.

[30]  F. C. Lee,et al.  Modeling and dynamic analysis of paralleled DC/DC converters with master-slave current sharing control , 1996, Proceedings of Applied Power Electronics Conference. APEC '96.

[31]  S. Ostlund,et al.  A concept for an HVDC traction system , 1989 .

[32]  Shuhui Li,et al.  Control of HVDC Light System Using Conventional and Direct Current Vector Control Approaches , 2010, IEEE Transactions on Power Electronics.

[33]  B. G. Fernandes,et al.  Distributed Control to Ensure Proportional Load Sharing and Improve Voltage Regulation in Low-Voltage DC Microgrids , 2013, IEEE Transactions on Power Electronics.