Research On Combined Peak Regulation Strategy Of Multiple Power Supply With High Proportion Unconventional Units

Energy shortage,environmental pollution and greenhouse effect are the three major problems of energy development.The contradiction between the high-carbon power energy structure and the demand for low-carbon development is becoming increasingly obvious.Clean and low carbon has become one of the core goals of power industry development.With the low dispatching resources such as wind power,photovoltaic power and more nuclear power plants(NPP)integrated into grid,the peak-valley difference of load continues to increase and the situation of peak regulation is increasingly serious,the demand for NPP to participate in peak regulation is very urgent.Multiple power supply coordination and optimization has become the future development direction of peak regulation.In addition,the enhanced interaction between power grid and demand side and the advancement of energy storage have made some loads and energy storage equipment adjustable and controllable,and can provide valuable peak regulation auxiliary service,which also provides a new way to alleviate the peak regulation pressure.Based on the above background,this paper combines the peak regulation resources of generation side and demand side,studies the multiple power supply peak regulation strategy with high proportion NPP,and a three-stage combined peak regulation model is established.Firstly,according to the operation characteristics of various types of generating units,the output models are established,and considering the interaction between power grid and demand side,the relevant constraints of demand side resources are given.Secondly,the method of equivalent load is adopted to deal with the output of wind turbines,and the carbon trading mechanism is introduced to analyze the operation cost from two aspects of economy and low carbon.Considering the safety and flexibility of peak regulation of NPP,a nuclear-thermal-wind-hydroelectric power peak regulation optimization model considering carbon trading mechanism is established,and the optimal peak regulation mode and depth of NPP according to the system requirements are determined.On this basis,the influence of carbon price on the operating cost and carbon emission of the system is analyzed.Finally,based on scenario analysis,a virtual power plant composed of interruptible load and energy storage equipment is used to reduce the prediction error of equivalent load in the third stage of dispatching operation.The nonlinear mixed integer programming model is linearized by linearization and solved by YALMIP toolbox of MATLAB.In the example,rationality and effectiveness of the model are verified.The simulation results indicate that the proposed model can ensure the safe and flexible operation of NPP,release the peak regulation pressure of system,reduce the start-up and stop-down peak regulation of thermal power units and decrease the hydropower abandoned water,and effectively avoid frequent changes of the generating units due to load forecasting errors.And it can also reduce the operating cost and carbon emission of system and balance the economic and environmental benefits.