基于马尔科夫链的电力系统运行可靠性快速评估

Markov Chain-Based Rapid Assessment on Operational Reliability of Power Grid

针对电力系统可靠性分析中蒙特卡罗模拟法需要大量计算资源和收敛速度较慢的缺点,从运行角度出发,在设备具备故障率指数分布特性前提下,基于马尔科夫链,建立可快速对电力系统运行可靠性解析分析的模型。其核心体现在:首先,提出便于工程实现的电力系统运行状态划分为3类的准则,及其对应的状态空间转移表达;然后,基于电力系统运行历史数据样本(或模拟数据样本)得到电力系统运行等值的马尔科夫状态转移概率矩阵。在此基础上,利用状态转移概率矩阵和电力系统运行当前的状态,可快速解析未来一段时间内电力系统运行状态转移概率、平稳状态概率及首次故障平均时间等可靠性指标,实现电力系统运行可靠性的快速评估。RBTS 6节点算例的分析,验证了电力系统状态转移的马尔科夫特性,表明了该研究的有效性。

In view of the defects in power system reliability analysis that Monte Carlo simulation needs a lot of computational resources and it converges slowly,from the viewpoint of operation and based on Markov chain and under the premise that equipment failure rate complies with exponential distribution characteristics,a model,by which fast analytical analysis on power system operation reliability can be carried out,is proposed.The core of the proposed model lies in following aspects： firstly,a criterion to dividing power system operating conditions into three categories,which can be easily implemented in engineering practice,as well as corresponding state space transition expression are proposed;secondly,based on historical operation data or simulation data of power system,a Markov state transition probability matrix equivalent to power system operation is attained;thirdly,on this basis utilizing state transition probability matrix and current power system operating condition,such reliability indices for some time to come as operation state transition probability,steady state probability and mean time to first failure of power system can be rapidly analyzed to implement rapid assessment of power system operation reliability.Simulation results of RBTS-BUS6 system prove the Markov property of power system state transition and the effectiveness of this research.