Research On Dynamic Modeling And Optimal Control Of Gas Turbine In Multi-operational Scenarios

As one of the key coupling devices of power natural gas thermal power in energy Internet,gas turbine is widely used in power grid frequency regulation,cogeneration,distributed generation and other operation scenarios.The output power of gas turbine is affected by the changes of ambient temperature and system frequency.It is very important to simulate and analyze these effects correctly,otherwise it may lead to the wrong estimation of frequency response reserve of power system,and even lead to load shedding and power outage.Secondly,the gas turbine controller is affected by its time-varying,nonlinear and various operation scenarios;on the one hand,it is difficult to set the parameters of the controller;on the other hand,the parameters of the controller are fixed during operation,and the adaptive performance is poor;the dynamic performance of the gas turbine is limited,and the unreasonable control parameters even affect the stability of the power grid.Therefore,it is of great significance to study the key issues of gas turbine operation control under multiple operation scenarios to ensure its own safe,stable and efficient operation,and even promote energy interconnection.The main contents of this paper are as follows:Firstly,aiming at the problem that the output power of gas turbine is affected by the changes of environment temperature and system frequency,a dynamic model of gas turbine considering the influence of environment temperature and system frequency is established.According to the waste heat utilization mode of gas turbine,the operation scenarios are divided,and the dynamic model of gas turbine under multiple operation scenarios is established.Considering the influence of environmental temperature change on the output power of gas turbine,according to the test curve given by the manufacturer,the influence of environmental temperature on the output power is analyzed;according to the fuel flow of gas turbine,the operating conditions are divided,and the influence of system frequency change on the output power of gas turbine is analyzed.The simulation results show that the established model can dynamically evaluate the operation state of gas turbine under multiple operation scenarios,and provide simulation reference for actual operation;at the same time,it also provides an important model basis for the optimization design of gas turbine controller.Secondly,an improved particle swarm optimization(PSO)algorithm is proposed for the complexity of gas turbine system.Based on the dynamic model of gas turbine established in the previous paper,combined with the control objectives of gas turbine in different operation scenarios,the controller optimization model is established,and the improved particle swarm optimization algorithm is used to solve the problem.The particle swarm optimization algorithm is improved from four aspects,which effectively improves the convergence speed,optimization accuracy and robustness of the algorithm for solving the optimization parameters of gas turbine controller.The simulation of gas turbine power generation system under different operation scenarios and different load disturbances is carried out.The results show that the proposed method can effectively improve the response speed of gas turbine to load disturbance under multiple operation scenarios,and protect the gas turbine from the influence of dangerous combustion chamber temperature.Finally,aiming at the problem that the controller’s adaptability is poor due to the fixed control parameters,an on-line design method of gas turbine controller parameters based on variable universe fuzzy control is proposed.Taking the controller parameters obtained by the off-line optimization design method as the initial values,the parameters of the gas turbine controller are adjusted online by fuzzy control,and the fuzzy rules are established according to different control objectives;the fuzzy universe is adjusted adaptively by the variable universe method,which improves the application scope of the fuzzy rules.Based on the gas turbine power generation system under different operation scenarios and different load disturbances,the control effect and robustness of the controller under the online design method are simulated and analyzed.The results show that the design method can effectively improve the adaptive performance of the gas turbine controller,and further improve the response speed of the gas turbine under multi operation scenarios;at the same time,the design method is simple,the amount of calculation is small,and less observable state variables are required.