Reduced-Order Dynamic Model of Modular Multilevel Converter in Long Time Scale and Its Application in Power System Low-Frequency Oscillation Analysis

A reduced-order dynamic phasor model of modular multilevel converter (MMC) in long time scale, which is applied for power system low-frequency oscillation analysis, is investigated. A tenth-order dynamic phasor model is derived in consideration of the internal circulation current dynamic of MMC. The model is verified via electromagnetic transient simulation. Then, an application of the singular perturbation method to MMC model reduction is presented. Separation of eigenvalues is used as a characterization of time scales and small time constant states is eliminated in the full-order model of MMC. MMC high-voltage direct current (HVdc) models with various orders are embedded into the four-machine two-area system to compare the low-frequency oscillation analysis results. The frequency domain analysis and time domain simulations show that the second-order model has satisfactory performance in describing the low-frequency characteristics of MMC. Moreover, the influence of MMC-HVdc transmission power and outer loop controller parameters on low-frequency oscillation is investigated using the second-order model. The effectiveness of reduced-order model in supplementary controller parameter design is also validated by comparing the difference in the response of various-order models to supplementary frequency-based control.

[1]  Anjan Bose,et al.  Modeling and Analysis of HVDC Converter by Three-Phase Dynamic Phasor , 2014, IEEE Transactions on Power Delivery.

[2]  Hao Yuan,et al.  Modeling of Grid-Connected VSCs for Power System Small-Signal Stability Analysis in DC-Link Voltage Control Timescale , 2017, IEEE Transactions on Power Systems.

[3]  Christian Rehtanz,et al.  A Virtual Synchronous Generator Control Strategy for VSC-MTDC Systems , 2018, IEEE Transactions on Energy Conversion.

[4]  Feng Liu,et al.  Modeling of DFIG-Based Wind Turbine for Power System Transient Response Analysis in Rotor Speed Control Timescale , 2018, IEEE Transactions on Power Systems.

[5]  Reza Iravani,et al.  Dynamic Interactions of the MMC-HVDC Grid and its Host AC System Due to AC-Side Disturbances , 2016, IEEE Transactions on Power Delivery.

[6]  Peter W. Sauer,et al.  Power System Dynamics and Stability , 1997 .

[7]  G. J. Rogers,et al.  Modeling of generators and their controls in power system simulations using singular perturbations , 1998 .

[8]  Joe H. Chow,et al.  Time-Scale Modeling of Dynamic Networks with Applications to Power Systems , 1983 .

[9]  Jovica V. Milanovic,et al.  The Effect of VSC-HVDC Control on AC System Electromechanical Oscillations and DC System Dynamics , 2016, IEEE Transactions on Power Delivery.

[10]  Luis Rouco,et al.  Active Power Control Strategies for Transient Stability Enhancement of AC/DC Grids With VSC-HVDC Multi-Terminal Systems , 2016, IEEE Transactions on Power Systems.

[11]  Alessandro Beghi,et al.  Model reduction techniques in tokamak modelling , 1997, Proceedings of the 36th IEEE Conference on Decision and Control.

[12]  Zheng Xu,et al.  Impacts of three MMC-HVDC configurations on AC system stability under DC line faults , 2015, 2015 IEEE Power & Energy Society General Meeting.

[13]  Jon Are Suul,et al.  Improving Small-Signal Stability of an MMC With CCSC by Control of the Internally Stored Energy , 2018, IEEE Transactions on Power Delivery.

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

[15]  Maryam Saeedifard,et al.  Control and Stability Analysis of Modular Multilevel Converter Under Low-Frequency Operation , 2015, IEEE Transactions on Industrial Electronics.

[16]  Liang Qin,et al.  Global asymptotic stability assessment of three‐phase inverters with saturation , 2018, IET Power Electronics.

[17]  Xavier Guillaud,et al.  On the modeling of MMC for use in large scale dynamic simulations , 2016, 2016 Power Systems Computation Conference (PSCC).

[18]  Nilanjan Ray Chaudhuri,et al.  Stability Analysis of Vector-Controlled Modular Multilevel Converters in Linear Time-Periodic Framework , 2016, IEEE Transactions on Power Electronics.

[19]  Xiaorong Xie,et al.  A Multirate EMT Co-Simulation of Large AC and MMC-Based MTDC Systems , 2018, IEEE Transactions on Power Systems.

[20]  George C. Verghese,et al.  Rational approximation via selective modal analysis , 1982 .

[21]  Yunjie Gu,et al.  Reduced-Order Models for Representing Converters in Power System Studies , 2018, IEEE Transactions on Power Electronics.

[22]  Lennart Harnefors,et al.  Impact on Interarea Modes of Fast HVDC Primary Frequency Control , 2017 .

[23]  Dragan Jovcic,et al.  Phasor model of Modular Multilevel Converter with circulating current suppression control , 2015, 2015 IEEE Power & Energy Society General Meeting.

[24]  Joe Chow,et al.  A Sparsity-Based Technique for Identifying Slow-Coherent Areas in Large Power Systems , 1984, IEEE Transactions on Power Apparatus and Systems.

[25]  Zhengchun Du,et al.  Dynamic equivalent model of VSC based on singular perturbation , 2016 .

[26]  Istvan Erlich,et al.  Analytical investigation of factors influencing controllability of MMC-VSC-HVDC on inter-area and local oscillations in interconnected power systems , 2016, 2016 IEEE Power and Energy Society General Meeting (PESGM).

[27]  Jinyu Wen,et al.  Dynamic phasor modelling and operating characteristic analysis of half-bridge MMC , 2016, 2016 IEEE 8th International Power Electronics and Motion Control Conference (IPEMC-ECCE Asia).

[28]  Jinyu Wen,et al.  Small-signal modeling of MMC based DC grid and analysis of the impact of DC reactors on the small-signal stability , 2018, International Journal of Electrical Power & Energy Systems.

[29]  Liang Qin,et al.  Modeling and Initialization of Modular Multilevel Converter Based High-voltage DC Transmission in Power System Dynamics Simulations , 2018, 2018 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC).

[30]  Zhu Lin,et al.  Electromechanical modelling of modular multilevel converter based HVDC system and its application , 2017, 2017 IEEE Conference on Energy Internet and Energy System Integration (EI2).

[31]  L. Rouco,et al.  Dynamic patterns and model order reduction in small-signal models of doubly fed induction generators for wind power applications , 2006, 2006 IEEE Power Engineering Society General Meeting.

[32]  Istvan Erlich,et al.  Generic Model of MMC-VSC-HVDC for Interaction Study With AC Power System , 2016, IEEE Transactions on Power Systems.

[33]  Dragan Jovcic,et al.  Small signal dynamic DQ model of Modular Multilevel Converter for system studies , 2016, 2016 IEEE Power and Energy Society General Meeting (PESGM).

[34]  Jon Are Suul,et al.  Generalized Voltage-Based State-Space Modeling of Modular Multilevel Converters With Constant Equilibrium in Steady State , 2017, IEEE Journal of Emerging and Selected Topics in Power Electronics.

[35]  Jing Ma,et al.  Robust Stochastic Stability Analysis Method of DFIG Integration on Power System Considering Virtual Inertia Control , 2017, IEEE Transactions on Power Systems.