Requirement of Flexible Load Research Under the Grid-Connected Large Amount of Renewable Energy

Abstract

With the large-scale wind power and photovoltaic bases construction in the power grid, the penetration rate has gradually increased. The characteristics of randomness, intermittence, back regulation, large output fluctuation and inaccurate prediction threaten the power grid development. The power grid only relies on the rotating reserve capacity of thermal power units to overcome the impact of renewable energy output fluctuation, and power grid peak shaving will face great difficulties. With the deepening of economic development and transformation in China, heavy industry and high energy consuming industries have declined, the living standards of people have improved, and the power consumption of tertiary industries such as civil load, commerce and service industry has increased. All these increase the peak valley difference, worsen the load characteristics, and for the peak regulation capacity higher requirements of the system were put forward. At the same time, the proportion of new loads with dual characteristics such as electric vehicles and energy storage systems with the ability to interact with the power grid is increasing. With the continuous advancement of power system reform and the continuous improvement of power market mechanism, the load side has the feasibility of participating in system regulation. Therefore, under the new situation, the high proportion of renewable energy integration, the increase of system flexible load proportion and application all increase the uncertainty and difficulty of power grid operation conditions. It is urgent to establish a power system peak shaving resource coordination and optimization method and strategy considering flexible load peak shaving capacity. It is used to guide the coordinated and optimal operation of flexible load participating in system peak shaving when the proportion of renewable energy connected to the grid is high.