Design Of SVC Nonlinear Control For Multi-machine Power System Considering Output Constraints

As the power system continues to grow and expand,it becomes more complex,so ensuring the safe and stable operation of the power system is essential.Static Var Compensation(SVC)is an efficient and flexible reactive power compensation device in FACTS devices,which is widely used in multi-machine power systems.Constraints the power angle difference output of the multi-machine power system,enabling the generator to run synchronously when the system fails.In this paper,considering the output constraints of multi-machine power system,based on backstepping method and Lyapunov stability theory,combined with adaptive control and sliding mode control,the transient stability problem of multi-machine power system with SVC is studied.The research includes the following parts:(1)For the multi-machine power system with SVC,the transient stability problem of the system is studied considering the constraint of system power angle difference output.Firstly,the backstepping method is applied to construct the constrained Lyapunov function,and a constrained nonlinear SVC controller is designed.Then,combined with sliding mode control,a class K function is introduced and an improved constrained sliding mode nonlinear SVC controller is designed.(2)Further consider the uncertainty of the damping coefficient in the multi-machine power system.Firstly,based on the backstepping method,combined with the constrained Lyapunov function and adaptive control,a constrained adaptive SVC controller is designed.Then,using the improved backstepping method and sliding mode control,an improved constrained sliding mode adaptive SVC controller is designed.(3)Comprehensive consideration of the uncertainty of the damping coefficient and unknown external interference in the multi-machine power system.Firstly,the backstepping method is applied to construct a constrained Lyapunov function.Combined with adaptive control,a constrained adaptive SVC robust controller is designed.Then,using the improved backstepping method and introducing the norm-type continuous sliding mode term to suppress external interference,an improved constrained sliding mode adaptive SVC robust controller is designed.