考虑光伏不确定性的安全约束机组组合

Security-constrained unit commitment considering PV output uncertainty

基于区间估计理论,提出一种求解考虑光伏出力不确定性的安全约束机组组合(SCUC)方法。对于系统预测误差的不确定性模型,允许所做决策在一定程度上不满足模型约束条件,采用置信度控制不满足约束的风险,并考虑不确定性的极限情况。利用Benders分解算法,将不确定SCUC模型分解为无SCUC和考虑SCUC的线路潮流检测问题,形成适合于混合整数规划问题的主问题和子问题求解的计算方法 ,从经济性和安全性角度实现对考虑光伏不确定性的SCUC问题的优化。以光伏并网的WSCC 9节点、3机组系统为研究对象,在MATLAB编程环境中调用优化软件包CPLEX对混合整数规划问题模型进行求解,结果表明该方法可以简单、高效地解决含光伏及负荷预测误差不确定性的SCUC问题。

A method of SCUC（Security-Constrained Unit Commitment） considering the uncertainty of PV（Photo Voltaic） output is proposed based on the theory of interval estimation. It is allowed that the constraint conditions of the uncertainty model for system prediction error could not be satisfied in a certain degree,but the confidence level should be adopted to control the risk of unsatisfied constraints and the worst conditions of uncertainty should be considered. Benders algorithm is used to decompose the uncertainty model of SCUC into the line power flow detections,with and without consideration of SCUC,which can be solved by the calculation methods suitable for the mixed integer programming to realize the SCUC optimization considering the PV output uncertainty in the aspects of economy and security. As an example,CPLEX,an optimization software packet of MATLAB,is applied to solve the mixed integer programming model of WSCC 9-bus 3-generator system with grid-connected PV power and the results show that,the proposed method can simply and effectively solve the SCUC model considering the uncertainty of PV output and load prediction errors.