This paper investigates a control and protection strategy for a four-terminal modular multilevel converter(MMC)based high-voltage direct current(HVDC)system under a converter-side AC fault.Based on the system operatin...This paper investigates a control and protection strategy for a four-terminal modular multilevel converter(MMC)based high-voltage direct current(HVDC)system under a converter-side AC fault.Based on the system operating condition,a control and protection strategy against the fault with normal blocking of the converter is proposed.In practical,applications encountering such a fault,the MMC at the fault side may experience different conditions of blocking failure.The blocking failures may occur on:①the whole converter;②one converter arm;③one sub-module(SM)/several SMs of one converter arm;④other conditions.The phenomenon of the multi-terminal HVDC(MTDC)system following the fault is analyzed under the first three conditions with real-time simulations using the real-time digital simulator(RTDS).Based on the impact of different conditions on the MTDC system,the necessity of utilizing special control and protection is discussed.A special control and protection strategy is proposed for emergency conditions,and its effectiveness is verified by real-time simulation results.展开更多
Developing offshore wind power,particularly in deep waters,is recognized as a vital approach to tackling the energy crisis and facilitating a low-carbon transition.VSC-HVDC transmission,leveraging its technological pr...Developing offshore wind power,particularly in deep waters,is recognized as a vital approach to tackling the energy crisis and facilitating a low-carbon transition.VSC-HVDC transmission,leveraging its technological prowess,has emerged as the principal means for transmitting large-scale,remotely located offshore wind energy.In recent years,numerous VSC-HVDC grid interconnection projects for offshore wind farms have been com-missioned globally,with the technology itself continually advancing and improving.This paper,in light of prevailing technological trends,provides a comprehensive overview of the advancements in key technologies within VSC-HVDC transmission tailored to the requirements of offshore wind power evacuation,encompassing system topology,operating modes,control and protection systems,essential equipment,and platform config-urations.It further details the profiles of representative offshore wind power VSC-HVDC transmission and grid connection projects currently operational or under construction,and delves into the prospective development trajectories and future research avenues for offshore wind power vSC-HVDC transmission technology.展开更多
基金This work is supported by UK EPSRC and UK National Grid.
文摘This paper investigates a control and protection strategy for a four-terminal modular multilevel converter(MMC)based high-voltage direct current(HVDC)system under a converter-side AC fault.Based on the system operating condition,a control and protection strategy against the fault with normal blocking of the converter is proposed.In practical,applications encountering such a fault,the MMC at the fault side may experience different conditions of blocking failure.The blocking failures may occur on:①the whole converter;②one converter arm;③one sub-module(SM)/several SMs of one converter arm;④other conditions.The phenomenon of the multi-terminal HVDC(MTDC)system following the fault is analyzed under the first three conditions with real-time simulations using the real-time digital simulator(RTDS).Based on the impact of different conditions on the MTDC system,the necessity of utilizing special control and protection is discussed.A special control and protection strategy is proposed for emergency conditions,and its effectiveness is verified by real-time simulation results.
基金Supported by the National Science and Technology Project(2024ZD0801000).
文摘Developing offshore wind power,particularly in deep waters,is recognized as a vital approach to tackling the energy crisis and facilitating a low-carbon transition.VSC-HVDC transmission,leveraging its technological prowess,has emerged as the principal means for transmitting large-scale,remotely located offshore wind energy.In recent years,numerous VSC-HVDC grid interconnection projects for offshore wind farms have been com-missioned globally,with the technology itself continually advancing and improving.This paper,in light of prevailing technological trends,provides a comprehensive overview of the advancements in key technologies within VSC-HVDC transmission tailored to the requirements of offshore wind power evacuation,encompassing system topology,operating modes,control and protection systems,essential equipment,and platform config-urations.It further details the profiles of representative offshore wind power VSC-HVDC transmission and grid connection projects currently operational or under construction,and delves into the prospective development trajectories and future research avenues for offshore wind power vSC-HVDC transmission technology.
