摘要
电力系统频率稳定性是衡量交流系统是否安全稳定运行的一项重要指标。当互联网交流系统遭受较大的负荷突变时,系统频率受到扰动会产生区域间的频率振荡。为抑制交流系统的频率振荡,根据交直流系统中直流传输功率可进行快速调节和具有短时过载能力的特点,提出了将传统的负荷/频率控制(LFC)和直流功率调制进行协调控制的方案,并采用重叠分解技术和线性二次型最优控制理论相结合的方法设计了直流功率调制控制器。对一个典型的三区域交直流并联系统进行数字仿真,结果表明,该协调控制方案一方面利用直流功率的快速调节抑制了区域间的频率振荡和功率振荡,有效地降低了负荷变化时频率的最大偏移,另一方面利用传统的LFC消除了频率的稳态误差。
The frequency stability of power system is an important index of evaluating the level of safety and stability of the operating of power system. When a sudden load change occurs in an interconnected AC power system, system frequency will be disturbed and maybe become oscillatory. In order to suppress the frequency oscillation of AC system, according to the characteristic that for an AC/DC power system, the DC power can be regulated rapidly and can be overloaded for a while, a coordinated control strategy for the traditional load/frequency control （LFC） and DC power modulation is proposed, and the DC power modulation controller is designed by combining the techniques of overlapping decompositions with linear quadratic optimal control theory. The control method is simulated in a typical AC/DC parallel hybrid transmission system with three areas. The results show that on one hand, the inter-area frequency oscillation and power oscillation are suppressed by regulating the DC power rapidly, meanwhile, the maximum excursion of system frequency when the load changes is reduced; on the other hand, the steady error of frequency is eliminated by the conventional LFC.
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2011年第7期56-62,共7页
Power System Protection and Control
基金
国家自然科学基金重大项目资助(51037003)
国家自然科学基金资助项目(50877050)
国家科技支撑计划项目(2008BAA13B01)~~
关键词
频率稳定
负荷/频率控制(LFC)
重叠分解
线性二次最优控制
交直流系统
协调控制
frequency stability
load frequency control （LFC）
overlapping decomposition
linear quadratic optimal controlof linear system
AC/DC transmission system
coordinated control
