Error Study for Impedance Characteristics of Electromagnetic Transient Simulation Models of Direct-Drive Wind Turbine Generators Under the Scenario Connecting to MMC-HVDC
The oscillation problem of large-scale renewable energy grid-connected system still occurs frequently in China,which seriously impacts the safe and stable operation of the system.Wideband impedance scanning and electromagnetic transient simulation are impor-tant methods to achieve the risk assessment of wideband oscillation.The accuracy and completeness of the wideband impedance charac-teristics in the electromagnetic transient model of renewable energy units will directly influence the assessment outcomes.Taking the in-tegration of direct-drive wind turbine generators into the modular multilevel converter-based high voltage direct current(MMC-HVDC)system as an example,the wideband oscillation mechanism are elucidated from the perspective of impedance characteristics through the establishment of wideband impedance models for direct-drive wind turbine generators and the MMC system.On this basis,the potential oscillation risk frequency ranges and the degree of the oscillation risk are identified through the further analysis of wideband impedance characteristics of direct-drive wind turbine generators.Error requirements for the impedance characteristics of electromagnetic transient simulation models of direct-drive wind turbine generators connecting to the MMC-HVDC system are proposed by using the indicators of the numerical consistency and trend consistency.
万方数据
维普
