Resilient Control For Key Component Of All-electric Ship Energy Storage Unit Based On Improved MPC

With the continuous advancement of economic globalization and the rapid development of shipping industry,maritime transportation tasks have become more and more onerous,and the using traditional energy sources to propel ships has brought great challenges to marine environmental protection.In order to alleviate the energy crisis,it is imperative to develop the all-electric ship with greenness and high efficiency.As the energy buffer module of the DC microgrid of the all-electric ship,the energy storage unit plays an important role in timely response to load requirements such as electric propulsion devices.To better meet the load response requirements of all-electric ships,the control problem of the energy storage unit key component in all-electric ships has attracted widespread attention in recent years.Due to the flexibility and the superiority of dealing with the control problem of MIMO system,Model Predictive Control(MPC)algorithm is used more in the control problem of the energy storage unit in all-electric ships.Considering the cyber-physical coupling characteristics of the all-electric ship DC microgrid,in actual control process,the communication network between the controller and the key component of the energy storage unit is vulnerable to Denial of Service(DoS)attacks,leading that the impact on system stability with packet dropouts of the control signal can not be ignored.Therefore,aiming at the packet dropouts of the control signal of the all-electric ship energy storage unit caused by DoS attacks,it is an urgent need to study the resilient control strategy of its key component to suppress fluctuations in DC bus voltage,which guarantee the safe navigation of all electric ships.The main research contents and contributions of this thesis can be summarized as follows:(1)The traditional MPC algorithm is summarized and analyzed,and the basic principles of the traditional MPC algorithm are expounded.Then the basic architecture of the MPC algorithm is introduced,the relevant theoretical derivation is carried out,and the advantages of the algorithm are analyzed.(2)In view of a Cyber-Physical System(CPS)with packet dropouts of control signals caused by DoS attacks,a resilient MPC algorithm is derived considering packet dropouts.And then considering the high computational complexity caused by its inherent structure,an improved resilient MPC algorithm is designed.Based on Tree-Based MPC(TBMPC)algorithm with probabilistic packet dropouts caused by DoS attacks,the algorithm is pruned by using the timestamp attack detection results,and then a Simplified Tree-Based MPC(STBMPC)algorithm is proposed to greatly shorten the operation time and improve the operating efficiency of the algorithm without sacrificing the control effect,which lays the theoretical foundation for the research on the resilient control of the energy storage unit key component in the all-electric ship attacked by DoS attacks.(3)Considering the all-electric ship under DoS attack,based on the predictive control method of the model considering packet loss,a flexible control strategy for the key components of the energy storage unit of the all-electric ship is proposed,which reduces the fluctuation of the DC bus and improves the stability of the system.At the same time,the efficiency of the algorithm is improved.In order to study the control effect of the design algorithm in different application scenarios,the algorithm was simulated and analyzed for all-electric ships with constant power load and all-electric ships with pulsed power load respectively.The simulation results verify that under different all-electric ship load configurations,the algorithm proposed in this paper is effective in reducing DC bus voltage fluctuations and improving the operating efficiency of the algorithm,and has good elastic performance to withstand DoS attacks.