面向风电场并网的VSC-MTDC频率控制策略研究

文中建立了基于VSC-MTDC的风电场并网三端系统,充分利用直流响应可控性强,速度快的优点,根据柔性直流输电对有功功率和无功功率独立、快速控制的特点,提出了用VSC-HVDC与发电机调速器协调控制的方法,通过对给定有功功率控制器附加频率控制来提高交流系统频率稳定性。理论分析和仿真结果表明该控制策略能提高多端柔性直流输电系统的频率调整能力,当系统受到扰动时,能有效的改善系统频率稳定性。

Frequency control strategy of VSC-MTDC about wind power grid

This paper constructs a three-terminal system connecting wind farm grid based on VSC-MTDC, and makes fully use of the advantages of the DC response featuring with strong controllability and fast speed .Therefore, this pa-per proposes a coordinated control method of VSC-HVDC and governor according to the characteristics of the VSC-HVDC have control active power and reactive power independently and quickly , in virtue of setting additional frequen-cy control in the constant active power controller to improve AC system frequency stability .Theoretical analysis and simulation results show that the proposed control strategy can improve the frequency adjustment ability of multi -termi-nal HVDC system , and it can effectively improve the system frequency stability when the system is disturbed .