深入探讨柔性直流输电系统的功率运行区间控制策略,对于提高电能传输质量并保障系统稳定至关重要.在此背景下,提出了一种柔性直流输电系统在低短路比下的功率运行区间控制方法.首先,分析低短路比条件下柔性直流系统的功率运行特性和影响因素,并确定了限制模块化多电平换流器的柔性直流输电(modular multilevel converter-high voltage direct current,MMC-HVDC)稳态运行区域的约束条件.然后,基于这些约束条件,构建了柔性直流输电系统在低短路比下的功率运行区间的理论计算模型,并开发了低短路比柔性直流系统和弱交流系统相连的柔性系统功率运行范围的计算程序.最后,在仿真环境中使用逐点扫描法和隐函数绘图法绘制了MMC在PQ平面上的稳态运行区域的边界,互相印证计算结果的准确性,同时证实了所提控制方法的有效性.
A Power Operation Interval Control Method for Flexible DC Transmission System under Low Short-Circuit Ratio
Thoroughly exploring the power operation interval control strategy of flexible DC transmission systems is crucial for improving the quality of power transmission and ensuring system stability.In this context,this paper proposes a power operation interval control method for flexible DC transmission system under low short-circuit ratio.Firstly,the power operation characteristics and influencing factors of the flexible DC system under the condition of low short-circuit ratio are analyzed,and the constraints that limit the steady-state operation area of the flexible DC transmission of the modular multilevel converter-high voltage direct current(MMC-HVDC)are determined.Secondly,based on these constraints,a theoretical calculation model of the power operation interval of the flexible DC transmission system under low short-circuit ratio is constructed,and the calculation program of the power operating range of the flexible system connected by the flexible DC system with low short-circuit ratio and the weak AC system is developed.Finally,the boundary of the steady-state operation region of MMC on the PQ plane is drawn by using the point-by-point scanning method and the implicit function plotting method in the simulation environment to mutually the accuracy of the calculation results and verify the effectiveness of the proposed control method.
flexible HVDC transmissionsteady-state operating rangemodular multilevel convertershort circuit ratio
NETL
NSTL
万方数据
