不同输电方式下风电接入对传统火电次/超同步振荡影响研究

随着风电等新能源并网容量的增加，电网中风电的大规模接入为系统的稳定性带来了新的挑战。当风电机组接入火电系统时，风电机组与传统火电因交互影响产生的次同步振荡的机理尚未明确，因此值得进一步来探讨。文中采用特征值分析法建立了风火混合经交流串补及柔性直流输电并网外送系统的状态空间模型，并通过对比分析研究了风机的接入对传统火电固有振荡模式的影响，进一步地，通过改变并网距离等参数来分析系统结构参数对风机与火电交互作用引发的次/超同步振荡模式的影响；在此基础上，揭示了交流输电与直流输电两种不同输电方式下风电接入对传统火电次/超同步振荡的影响机理与因素；并利用PSCAD/EMTDC平台进行时域仿真证实了所建立系统的正确性。

Research on wind power integration on Sub/Super-synchronous oscillation of thermal power plants under different transmission modes

With the increase of grid connected capacity of new energy such as wind power, the large-scale access of wind power in the power grid has brought new challenges to the stability of the system. When the wind turbine is connected to the thermal power system, the mechanism of sub-synchronous oscillation caused by the interaction between wind turbine and traditional thermal power is not clear, so it is worth further discussion. In this paper, the eigenvalue analysis method is used to establish the state space model of wind fire hybrid AC series compensation and VSC-HVDC transmission grid connected transmission system, and the influence of fan access on the natural oscillation mode of traditional thermal power is studied through comparative analysis, By changing the grid connection distance and other parameters, the influence of system structural parameters on the sub/super-synchronous oscillation mode caused by the interaction between fan and thermal power is analyzed; On this basis, the influence mechanism and factors of wind power access on traditional thermal power sub-synchronous oscillation under AC transmission and VSC-HVDC transmission are revealed; The correctness of the system is verified by time-domain simulation on PSCAD / EMTDC platform.