Research On Wide Area Damping Control Method Of Power System Based On ARX Model And Artificial Immune System Theory

With the gradual expansion of my country's interconnected power grid,the structure of the power system is becoming more and more complex,and the resulting low-frequency oscillations threaten the safe and stable operation of the power system.How to suppress low-frequency oscillations has become a hot issue for scholars to explore.Damping control is one of the effective methods to suppress low-frequency oscillations,and Wide Area Measurement System Wide-area Measurement System can provide synchronized measurement data of important units and nodes in the interconnected grid,which makes it a part of damping control Powerful auxiliary tool.This paper focuses on the design of the wide-area damping controller in terms of wide-area control loop selection,controller structure design,and parameter configuration methods.The following research work has been done:1)Aiming at the problem of artificial immune wide area damping controller installation location and control signal selection,this paper is based on the Autoregressive eXogenous identification method with multiple input and multiple output items for control loop selection.Usually,the identification of low-frequency oscillations based on measurement data only processes and analyzes a single signal,and it is impossible to grasp the relationship between several oscillation modes in the system.The proposed method combines the response characteristics of the generator set control system to obtain the low-order transfer function model of the system by reducing the dynamic oscillation characteristics in the system by order reduction,and calculates the residue index to select the wide-area control loop.The simulation shows that the proposed method is simple in calculation and can accurately identify the system oscillation mode.2)For the traditional Power System Stabilizer,it is difficult to meet the damping control performance problem under various operation modes of the power grid.This paper draws on the Artificial Immune System theory to construct a wide-area damping control structure composed of innate immune part and adaptive immune part.Among them,the innate immune part is a traditional PSS structure,which has nothing to do with uncertain factors such as external interference;the adaptive immune part can adjust the original controller parameters in time according to the disturbance response of the system,and the combination of the two can achieve the overall dynamics Compensation to improve control performance under different operating conditions.3)In view of the problem of artificial immune wide-area damping controller parameter configuration method,this paper proposes an Improved Fireworks Algorithm,through adaptive radius adjustment of the explosion operator,the introduction of differential component mutation operator and change Three measures were selected to solve the problems of too fast convergence and poor searchability of the basic firework algorithm,and the performance test of the IFWA algorithm was performed using test functions.In addition,the Integral of Time and Absolute Error is used to construct an optimized objective function and corresponding optimized control model that reflect the dynamic response characteristics of the system,and the controller is optimally designed according to different disturbance responses of the system.The two-zone four-machine system and the England ten-machine system are used to verify the simulation,which is superior to the traditional wide-area PSS control effect,and enhances the system's anti-interference ability and dynamic stability.