摘要
风电功率具有强波动性和不确定性,其强波动性主要表现为较大的爬坡事件,而其强不确定性则表现为风电功率难以精确预测,两者都给电力系统运行带来了新的挑战。针对爬坡事件,建立了考虑风电爬坡事件约束的精确线性化的机组组合模型;针对风电功率难以精确预测,考虑用其预测值以及区间预测上、下限来描述风电场出力,从而通过线性鲁棒优化理论将该随机问题转化为一确定性问题后进行求解。以含风电的10机39节点系统为例进行算例分析,结果表明,对于一般的风电爬坡事件,爬坡事件约束是不起作用的,但对于风电波动速率较大的情况,考虑爬坡事件更能保证系统安全。由于所建模型为一线性混整规划模型,故可实现大规模求解并用于实际系统。
Wind power has the characteristics of volatility and uncertainty due to its large ramp events and difficulty of accurate prediction, which brings new challenges to power system operation. To cope with ramp event, this paper proposes an exact linearization unit commitment model with constraints of wind power ramp event. Wind power is described by its predicted values as well as the upper and lower limits of its interval prediction to solve the inaccurate prediction. Thus, this stochastic problem can be converted into a deterministic problem by linear robust optimization theory. Case studies are carried out based on a 10-machine 39-bus system with wind farms integration. Simulations show that, the constraints of large wind power ramp event should be considered to guarantee the security of power system, although the constraints of small wind power ramp event have no effect on unit commitment. In addition, since it is linear mixed integer programming, the proposed unit commitment model can be used in practical large-scale systems.
出处
《电工技术学报》
EI
CSCD
北大核心
2015年第24期188-195,共8页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(50937002)
国家高技术研究发展计划(863计划)(2011AA05A112)资助项目
关键词
爬坡事件
预测误差
机组组合
鲁棒优化
风电功率
Ramp event
prediction error
unit commitment
robust optimization
wind power