Increasing efforts to develop renewable energy has become a key measure for countries around the world to alleviate energy shortages and environmental problems. Mobilizing demand side flexible resources can increase the configurable flexibility capacity in the power system, improve energy utilization efficiency and reduce the operating costs of power system. Accurate assessment of the schedulable potential of flexible resources on the demand side can cope with the impact of high proportion of renewable energy grid connection on the power system, adjust and control the system quickly and accurately, so as to realize a balance of energy supply and demand.