风电并网系统次/超同步振荡的动态监测方法研究

近年来,我国大规模风电基地中出现了新型次/超同步振荡问题,其频率具有时变特性。已有的同步相量测量单元(PMU)和广域测量系统无法准确监测其动态发展过程。鉴于此,本文首先探讨了次/超同步谐波对传统PMU算法的不良影响,剖析谐波引起基频相量测量误差的根源。其次,提出一种具有频率自适应控制能力的次/超同步谐波相量检测方法,能够准确判断系统中是否出现次同步振荡,并检测出基波相量和次/超同步谐波相量。最后,通过搭建实际系统的电磁暂态仿真模型分析验证了改进算法的有效性和精确性。

Research on Dynamic Monitoring Method for Sub/Super-synchronous Oscillation in Wind Power Systems

In recent years, a new type of sub/super- synchronous oscillation (SSO) occurred in the large-scale wind power system in China. The frequency of these emerging SSO issues gradually changes with time. The exiting phasor measurement units (PMUs) and wide-area measurement system (WAMS) cannot monitor the dynamics of sub/super-synchronous oscillations in wind power systems. To deal with these challenges, this paper investigates impacts of the sub-synchronous and super-synchronous harmonics on traditional PMU algorithms. The root cause of measurement error caused by harmonics is thoroughly analyzed. A new method which can automatically adapt its frequency is proposed to track the fundamental phasor, sub-synchronous phasor and super-synchronous phasor simultaneously. The electromagnetic transient simulations based on a practical wind power system are carried out to validate the effectiveness and accuracy of the improved method.