Research On Autonomous Scheduling Strategy Of Micro-grid Based On Bi-level Optimization

With the continuing emergence of global issues such as environment pollution,energy shortage and so on,the exploitation of clean energy is gradually drawing the attention from all over the world.Through physical or chemical way of conver sion,taking photovoltaic & wind power generation for instance,clean energy is converted into electricity which is more convenient to consume and being utilized secondarily afterwards in the grid.However,the grid is faced with pressure for peak shaving to a certain extent according to the volatility and intermittence attached to clean energy.Moreover,the grid's ability of adopting clean energy turns out to fall behind the growing amount of accessible clean energy which leads to increasingly intensified energy waste for solar energy and wind energy.The safety and stability of system operation is being tested.As the construction of smart grid is stepping forward,the traditional vertically integrated topology is transforming to a new flat type with the interconnection of various micro-grids as a result of the increasing intelligence of the more and more connected grid.Application of electric information acquisition system and popularization of intelligent electric appliances like electric vehicles makes it possible for loads to be scheduled rather than just being cut down when necessary.The traditional way of scheduling is incapable of exploring the scheduling potential of loads because its inherent deficiencies.Micro-grid,as a new schedulable type of grid structure,has great potential on helping the system to adopt clean energy and gradually becomes a new research hotspot.This paper focus on the autonomous scheduling strategy under the background of global energy internet,aiming at the optimal arrangement of schedulable resources within the micro-grid to improve the energy utility efficient and the adoption level while degrading peak shaving pressure.First of all,the operation modes and topology of present micro-grid is expounded with the ability and forms of micro-grids participating in the system scheduling plan based on smart grid.Then,the autonomous scheduling strategy of smart industry district,which is chosen as a typical kind of micro-grid,is proposed.A bi-level optimization model is built where the uncertain factors are dealt with through chance constraints.Finally,a research on combined heat and power scheduling is carried out focusing on the combined multi-type energy scheduling in micro-grid where the internal energy flow and conversion is analyzed.Then the micro-grid is modeled and the model is improved through the method of robust optimization to seek for the economical scheduling strategy under the situation that the system is operating under the worst conditions.Cases are studied for each model to verify the validation of the model as well as the feasibility of the proposed strategy.