Research On Adaptive Distributed Control Of Multi-Machine Infinite Busbar Excitation Systems With SVC

With the development of the world economy and new energy power generation,the scale of modern power systems has expanded rapidly.The gradual implementation of regional networking even nationwide and multinational networking,as well as the continuous introduction of new components and new technologies,have made the grid structure increasingly complex,which poses new challenges to the stability of power systems.In terms of improving the dynamic performance and stability of power systems,the performance of existing equipment can be effectively improved by introducing nonlinear control methods.Among the many methods,the excitation control of the generator is the most commonly used technical means.In this thesis,based on Lyapunov stability theory,a scheme based on distributed adaptive dynamic surface algorithm and RBF neural network algorithm is proposed for multi-machine infinite busbar excitation systems,and it is completed the design of the excitation controller for multi-machine power systems.The main research contents of this thesis are as follows:A control scheme combining sliding mode control and distributed adaptive dynamic surface control is proposed for multi-machine power systems with SVC.When there are coupling interconnection and time delay in the multi-machine power systems,the information of each subsystem can be collected and processed by limited coverage lemma to achieve distributed control.In the process of controller design,the improved a hysteresis quantizer is used to effectively reduce the jitter of the system,which is closer to the actual control.Using the RBF neural network as an approximator to estimate unknown parameters and uncertainties in the systems model,and by replacing the estimation of the weight vector itself with the norm of the weight vector,the calculation step is simplified,which is more suitable for online control.It is verified by MATLAB that the controller can improve the power angle performance of the multi-machine power systems,and all the control signals in the closed-loop system can converge quickly,achieving semi-global and finally bounded.The controller design based on adaptive dynamic surface algorithm is implemented for multi-machine electric excitation systems with dead zone.The dead zone is analyzed and the corresponding method is adopted to improve the control effect.At the same time,combining the adaptive dynamic surface with the error conversion function and the tracking performance function can improve the dynamic quality of the systematic error.The static var compensator is equipped at the busbar to enhance the reactive power adjustment capability of the system and enhance the transient stability of the system.The MATLAB simulation proves that the controller can keep the tracking error of the multi-machine power systems always between the tracking performance functions,and all the signals are semi-global and finally bounded.The simulation results can verify the effectiveness of the proposed control scheme.