Hydropower,thermal Power,wind Power And Photovoltaic Joint Dispatch Considering Uncertainty

The rapid development of wind power and photovoltaics promotes the reform of my country's energy structure and the energy saving and emission reduction of the power system.The high proportion of renewable energy grid connection will be an inevitable trend in the development of my country's power system.With the integration of large-scale wind power and photovoltaic grids,the dispatching method of the power system changes from deterministic to probabilistic,which makes traditional dispatching methods challenging.Wind power and photovoltaic are random and uncertain,which leads to an increase in the peak-valley difference of the equivalent load of the system,threatening the safety and stability of the power system.Coordinated scheduling through flexible power compensation is an effective measure to increase the amount of wind and solar energy consumption and ensure the safety and stability of the system.In the multi-energy power system of hydropwer,thermal power,wind power and photovoltaic improving the peak shaving capacity of hydropwer and thermal power is an important means to solve the peak shaving of the power grid from the power supply side.This paper considers the uncertainties of wind power and photovoltaics,deeply analyzes the cascade hydropower cooperative compensation mechanism and the peak shaving mechanism of the hydropwer and thermal power system,and on this basis,studies the dispatch mode of the hydropower,thermal power,wind power and photovoltaic system considering the controllable load peak shaving and the randomness of the wind power and photovoltaic output.The main findings are as follows:(1)Statistical indicators are used to analyze the influence of wind power and photovoltaic volatility,uncertainty and anti-peaking characteristics on the power system.The results show that the reverse peaking characteristics and frequent fluctuations of wind power and photovoltaic not only increase the peak-valley difference of the equivalent load of the power system,but also increase the fluctuation range and speed of the equivalent load.This requires that the flexible power supply has rapid adjustment ability and depth peak-shaving characteristics.From this,it can be seen that the key factor restricting the absorption of wind power and photovoltaic is the insufficient peak-shaving capability of the system.(2)In order to ensure the coordination among cascade hydropower stations,tap the peak-shaving capacity of cascade hydropower stations,proposing a cooperative scheduling mechanism for cascade hydropower stations that are connected to large-scale wind power and photovoltaic power plants.The goal is to consider the comprehensive utilization constraints and hydraulic constraints,and establishes a cooperative peak shaving model for cascaded hydropower stations based on the principle and principle of peak shaving.Three sets of comparison schemes are proposed to verify the proposed model.The results show that the cooperative peak-shaving model of cascade hydropower stations improves the coordination among various hydropower stations.(3)The combined peak and peak mode of the hydropwer,thermal power system is very important for the operation of the power system of the hydropwer,thermal power supply.Considering the water inflow of cascade hydropower stations in different seasons,the comprehensive utilization requirements of reservoirs and the peak-shaving situation of thermal power during heating period,a joint peak-shaving mode of hydro-thermal system is proposed,and a mathematical model of joint peak-shaving of hydro-thermal system with the largest wind power and photovoltaic consumption as the target was established.The nested cascade hydropower station peak-shaving model is nested,and the results prove the effectiveness of the combined peak-shaving mechanism of the hydro-thermal system,and reveals that the key factor for accommodating wind power and photovoltaic is the power generation space where thermal power can be compressed.(4)In order to further study the dispatch mode of hydropwer,thermal power wind power and photovoltaic system considering the randomness of controllable load peak shaving and wind power generation,a model of hydropwer,thermal power wind power and photovoltaic joint dispatch considering the randomness of controllable load peak shaving and the uncertainty of wind power and photovoltaic is established.the model considers reservoir constraints,Thermal power climbing constraints,etc.with the goal of minimum wind abandonment and photovoltaic loss of the system as the goal,the particle swarm optimization algorithm is used to calculate the maximum start-up capacity of the thermal power and the output plan of the hydropower station.In order to verify the validity of the model,the calculation results are used as input to the joint peak-shaving model of the hydro-thermal system.The results show that the maximum startup capacity of the thermal power calculated by the proposed model is reasonable.