Power Load Frequency Control Considering Demand Response Under Cyber Attack

Under the situation of high-proportion intermittent renewable energy integration,the regulation resources at the demand side participating in power load frequency control(LFC)helps to relieve the frequency regulation pressure of the traditional power plants,reduce the cost and improve the regulation performances.Compared with the traditional power grid,modern power system is highly dependent on the communication network,especially the communication network extending to the power customer is much weaker,and thus the risk of the power system suffering from cyberattacks has increased dramatically.This thesis studies the detection and defense strategies against false data injection attack and Do S attack for the LFC problem considering the demand response.The main work and results are as follows:(1)For the problem of the demand resources participating in secondary frequency regulation of power system,an equivalent model of flexible load is established,and the dynamic performances of the LFC considering the demand response are analyzed.First,on the basis of the traditional LFC model,a first-order inertia model is used to represent the dynamic regulation characteristics of the load aggregator,and thus the equivalent model of the LFC with the demand response is established.Finally,the simulation experiment verifies that demand resources participating in the frequency regulation of power system can effectively restrain the frequency fluctuation and reduce area control error(ACE).(2)For the problem of false data injection attacks on the LFC,an attack detection algorithm basd on Kalman filter and a defense strategy for the LFC system are proposed.First,the Kalman filter algorithm is designed to detect whether the frequency signals and the tie-line power signals suffer from false data injection attacks.Then,considering the high redundancy of communication links in power systems,a selection algorithm that is used to determine which communication links are secure is proposed for defending against the fasle data injection attacks.Finally,the simulation results show that the proposed method can effectively detect and defend against the false data attacks and improve the security of the LFC system.(3)For the problem of the Do S attacks on the LFC system,an attack identification algorithm based on the communication delay detection is proposed.First,to determine whether the system frequency signals and tie-line power signals suffer from the Do S attacks,the communication delay of the feedback signals is calculated to determine whether feedback signals are secure.Then,the proposed selection algorithm in(2)is adopted to extract the secure feedback signals to defend against the Do S attacks.Finally,the simulation results show that the proposed algorithm can effectively resist the Do S attacks and guarantee the frequency regulation performances of the LFC system.