Study On Modeling And Optimization Control Of Wind-photovoltaic Integrated Microgrid Containing Pumped Hydropower Energy Storage

With the increase of power demand,traditional fossil energy is depleted and environmental problems are becoming more serious.Energy issues have restricted the sustainable development of countries around the world.The development and use of renewable energy can effectively solve the above problems and it is a hot issue in today's society.The advantages of distributed generation,including renewable energy generation,are mainly reflected in efficiency,cost,and performance.The distributed power supply has a negative impact on the power system's power flow,harmonics,stability and other aspects,because of its random output,fluctuations and other characteristics.And the performance of energy storage equipment restricts the large-scale development of microgrids.For this reason,the idea of using a small pumped-storage generating unit as the energy storage element of the microgrid is proposed.The modeling work of pumped storage units and microgrids is carried out.The optimization algorithm is used to optimize the unit controller parameters,and the performance of pumped storage units and microgrids is improved.It has practical engineering application value and great significance.For the modeling work of pumped storage units and microgrids,the nonlinear characteristics of pumped storage units are complex.The cross-overlap problem of the full-character curve of the pump-turbine and the uncertain disturbances of the wind and photovoltaic systems in the microgrid increase the pumped-storage capacity.Unit and microgrid modeling and control difficulty.To this end,on the basis of a comprehensive analysis of pumped-storage characteristics and the establishment of refined single-machine models,micro-grid models suitable for different simulation purposes were established for different simulation needs of microgrids.In order to improve the performance of pumped storage and its control performance in the microgrid,the optimization of the control parameters based on the optimization algorithm was further studied to ensure the safe and stable operation of the system.The main work and innovative achievements of the paper are as follows:(1)Aiming at the research needs of the pumped storage unit simulation and optimization operation,the nonlinear model of the speed regulation system of the pumped storage unit was studied and established;for the different simulation requirements of the microgrid,the uncertainties of the new energy generation system were considered and the application was established.Micro-grid models for different simulation purposes are the basis for the study of system optimization.(2)For the optimization of control parameters,a new heuristic optimization algorithm—an artificial flock algorithm—was proposed.The algorithm simulated the social behavior of herds through the sheep-head effect,stochastic exploration,and competition mechanism,and designed the comparison experiments with the other seven optimization algorithms and compared the optimization of the test benchmark function;(3)Aiming at the problem of optimization of multiple parameters for overshoot of overshoot and turn-on time of pumped storage units,a smart boot strategy was introduced.The traditional boot and smart boot strategies were optimized using an artificial flock algorithm.The start-up method improves the startup performance of pumped storage units;(4)Study on modeling methods for different simulation control needs of pumped-storage-energy storage-wind-solar complementary microgrid,research on micro-grid load frequency control and transient simulation control,and adopting an artificial flock algorithm to control pumped-storage generating units.The instrument parameters are optimized to improve the control effect of the pumped-storage unit in the microgrid.