考虑暂态安全性的低频低压减载量的全局优化

OPTIMAL PARAMETER-SETTING OF UNDER-FREQUENCY AND UNDER-VOLTAGE LOAD SHEDDING FOR TRANSIENT SECURITY

指出了低频和低压减载装置的整定不仅要满足静态和中长期动态对频率和电压的安全性要求 ,而且要满足暂态过程中的频率和电压安全约束。通过详细模型的时域仿真 ,在各种运行方式及故障集下寻找使系统暂态安全且总体控制代价最小的减载策略。给出了其减载量优化问题的数学描述 ,以减载代价最小为目标函数 ,把低频和低压减载控制作为多级控制序列。根据暂态频率和电压安全裕度指标计算减载的性价比 ,把性价比最大的决策作为下一级的初始条件 。

Parameter setting for under-frequency load shedding (UFLS) and under-voltage load shedding (UVLS) should not only ensure static security of frequency and voltage, but also suffice their transient security. Concerning transient security, an algorithm for searching the optimal load shedding scheme is proposed. UFLS and UVLS are treat as multi-stage control actions, and the total cost of load shedding is taken as the objective function. Based on the proposed security margins of transient frequency and transient voltage, the effectiveness-cost-ratio is used to conduct the stage-by-stage searching with detailed time-domain simulations under various operating conditions and faults.