Power System Flexibility Indicators Considering Reliability in Electric Power System with High-Penetration New Energy

In order to clarify the concept of power system flexibility, a definition of flexibility considering reliability is proposed by comparing and analyzing various literatures. Combined with the definition and the existing reliability index and flexibility index, a flexibility index considering reliability is proposed. According to the proposed flexibility index, the flexibility evaluation system is constructed, and the flexibility demand model and supply model are established. For the future high proportion of new energy power system, using IEEE reliability test systems, a variety of new energy proportion scenarios are constructed, and Monte Carlo method is applied to evaluate the changes of reliability index and flexibility index under different scenarios. It shows that under the background of high proportion of new energy, the result of traditional reliability index will be conservative, and it is suggested to use the flexibility index considering reliability.