| With China’s continuous economic and social development and the continuous adjustment of energy structure,hydroelectric energy development is developing rapidly.The pumped storage power station is responsible for peak regulation and frequency regulation and accident backup in the power grid,which is of great significance for maintaining the safe and stable operation of the power system.However,the speed control system of the pumped storage unit has strong non-linearity and time-varying nature,which makes its control problem very complicated.Pumped-storage units have many operating conditions and frequent conversions,when the operating conditions change drastically,great water hammer pressure may be generated,which threatens the safe operation of pumped-storage power stations and stability of the power system.Therefore,carrying out pumped storage unit speed control system modeling,control law optimization and transition process calculation research is of great significance for exploring the inherent characteristics of pumped storage units,improving unit control performance,and ensuring the stable operation of pumped storage power plants and power systems.First of all,this paper thoroughly studied the operating principles and dynamics characteristics of the key facilities of the pumped storage unit speed control system,established its precise nonlinear model.Then combined the TS fuzzy model identification theory on the nonlinear model to explore the generalized predictive control scheme of the pumped storage unit speed control system.At last,developed a powerful visual calculation software for the transition process of the pumped storage power station based on the Java language.The main research and innovative results of this paper are as follows:(1)Establishment of a refined model of pumped storage units speed control system.Fully consider boundary conditions in the pumped-storage power station,including differential surge chambers,pressure regulating valves and gate grooves,according to the characteristic line method to establish the characteristic line model of the water pipeline and boundary conditions.Based on the improved BP neural network combined with stochastic gradient boosting algorithm,the full characteristic curve of the pump and turbine is encrypted and extended,which significantly improves the interpolation accuracy.Simulation is carried out according to power station example and compared with the measured data,which verifies the rationality and accuracy of the established model.(2)Obtainment of the CARIMA model of generalized predictive control based on T-S fuzzy model identification.By analyzing the characteristics of the CARIMA model used in generalized predictive control,combined with the TS fuzzy model theory and its identification method,the feasibility of obtaining a CARIMA model that can be applied to predictive control through TS fuzzy model identification is demonstrated,and the specific steps of generalized predictive control based on T-S fuzzy model identification are given.(3)The generalized predictive controller is designed and verified by experiments.Use the T-S fuzzy model theory to identify the speed control system of the pumped-storage unit,and verify the identification accuracy,and use the obtained identification model as the CARIMA model of the speed-regulating system of the pumped-storage unit to design a generalized predictive controller.Through the start-up and frequency disturbance simulation experiment and the comparison experiment with PID and FOPID controller under multiple working conditions,the good control performance of the generalized predictive controller is verified.(4)Development of pumped storage power station transition process visual calculation software.According to the modeling theory of the pumped storage unit speed control system,based on Java language and Eclipse integrated development environment,fully considering user’s usage habits and concerned transition process calculation results,a transition process calculation software CSTPP with complete functions,stable operation and fast calculation has been developed.And according to the power station example,this software is used to carry out multi-condition simulation calculation,which verifies the accuracy of CSTPP. |
