Impact of MTDC grid reconfiguration and control on the dynamics of the GB System

Multi-terminal DC (MTDC) grids are becoming increasingly popular for interconnecting non-synchronous generating resources such as offshore wind power plants (WPPs). The benefit of MTDC systems is that they can be reconfigured during contingencies to maintain the supply of power to the host AC systems. DC grid reconfiguration in MTDC systems will inevitably change the power injections to the host AC system, and will thus affect the dynamic behaviour of the AC system. This paper investigates the dynamic behaviour of the representative Great British (GB) transmission system (i.e. a reduced order dynamic model) for a series of reconfigurations in a meshed MTDC grid connecting offshore WPPs to the system. Hierarchical control strategies for the MTDC system including a DC power flow solver (PFS) and pilot voltage droop (PVD) are compared. From the analysis, it is observed that the reconfiguration of MTDC grid has a notable impact on large-disturbance dynamics of the GB transmission system.

[1]  M. Barnes,et al.  The influence of MTDC control on DC power flow and AC system dynamic responses , 2014, 2014 IEEE PES General Meeting | Conference & Exposition.

[2]  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.

[3]  Marta Molinas,et al.  Interaction of Droop Control Structures and Its Inherent Effect on the Power Transfer Limits in Multiterminal VSC-HVDC , 2017, IEEE Transactions on Power Delivery.

[4]  Alvaro Luna,et al.  A hierarchical control structure for multi-terminal VSC-based HVDC grids with GVD characteristics , 2013, 2013 International Conference on Renewable Energy Research and Applications (ICRERA).

[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]  Hong Rao,et al.  Architecture of Nan'ao multi-terminal VSC-HVDC system and its multi-functional control , 2015 .

[7]  Oriol Gomis-Bellmunt,et al.  Hierarchical power control of multiterminal HVDC grids , 2015 .

[8]  Alvaro Luna,et al.  DC Voltage Control and Power Sharing in Multiterminal DC Grids Based on Optimal DC Power Flow and Voltage-Droop Strategy , 2014, IEEE Journal of Emerging and Selected Topics in Power Electronics.

[9]  Kjetil Uhlen,et al.  Power System Security in a Meshed North Sea HVDC Grid , 2013, Proceedings of the IEEE.

[10]  Ehab F. El-Saadany,et al.  DC Voltage Regulation and Frequency Support in Pilot Voltage Droop-Controlled Multiterminal HVdc Systems , 2018, IEEE Transactions on Power Delivery.

[11]  Carl David Barker,et al.  HVDC grid control system based on autonomous converter control , 2016 .

[12]  B. Chaudhuri,et al.  Adaptive Droop Control for Effective Power Sharing in Multi-Terminal DC (MTDC) Grids , 2013, IEEE Transactions on Power Systems.

[13]  Mike Barnes,et al.  Offshore AC grid management for an AC integrated VSC-HVDC scheme with large WPPs , 2016, 2016 IEEE Power and Energy Society General Meeting (PESGM).

[14]  Jiuping Pan,et al.  Stability Analysis of VSC MTDC Grids Connected to Multimachine AC Systems , 2011, IEEE Transactions on Power Delivery.

[15]  Dirk Van Hertem,et al.  Impact of DC grid contingencies on AC system stability , 2017 .

[16]  O. Gomis-Bellmunt,et al.  Analysis of deviations on the optimal power flow operation of MTDC networks: A comparison between droop control and the DVC strategy , 2015, 2015 17th European Conference on Power Electronics and Applications (EPE'15 ECCE-Europe).