基于改进麻雀优化PID的波浪补偿控制方法OACSTPCD

With the continuous promotion of the 14th Five-Year Plan for offshore wind power,the demand for megawatt-level high-power off-shore fans in deep far sea areas has increased.However,in the process of offshore work such as lifting and installing the fans,the continuous fluc-tuation impacts of complex waves on the ship lead to a significant decline in the accuracy and efficiency,and even cause significant losses to per-sonnel safety and property.Effective wave compensation for engineering ships in the complex sea conditions can provide a stable working envir-onment to ensure accurate and efficient tasks.Therefore,a wave compensation control strategy based on the improved sparrow search PID al-gorithm was proposed in this paper and applied to the Stewart compensation platform.Firstly,based on Stewart compensation platform,the kinet-ic and inverse kinematics models of the wave compensation system were established,and an iterative solution algorithm of the positive solution model was designed.Then,the PID(Proportion Integration Differentiation)was used for wave compensation control since it is mature and easy for hardware implement.To get the suitable three parameters of PID for superior performances,the sparrow search algorithm was used to optim-ize the parameters.Whereafter,the Circle Chaotic Mapping method was used to initialize the values distribution to solve the problem of uneven initialization.The Cauchy Mutation and Reverse Learning methods were used to improve the global optimization ability of the algorithm.Finally,the motion of an engineering ship in class 4-6 sea state was input to the system,and the model was built with MATLAB/Simulink and carried out on the Stewart hardware platform to verify the effects of the compensation control method.In view of the above research,this paper mainly con-tains the following aspects:1)Building the simulation model of the wave compensation system.The SimMechanics tool in Simulink was used to establish a dynamic modle according to the mechanical structure and transmission mode of Stewart platform.The upper and lower layers were used as wave compensation system and ship motion simulation system respectively.The pose analysis and homogeneous coordinate transforma-tion were carried out,and the forward and inverse kinematics models were established.In the meantime,for the continuous ship trajectory,the it-erative solution algorithm of the forward solution model was designed and verified by simulation.2)Establishing the optimal control method of the wave compensation system.According to the model characteristics and control requirements of wave compensation,the PID control method was applied.The wave compensation system was controlled by PID based on the difference between the axis length reference displacement and the actual displacement detected by the encoder.PID parameters were optimized by the sparrow search algorithm,while corresponding improve-ments were made to address the shortcomings of the basic sparrow search algorithm.3)Simulation verifications based on wave compensation sys-tem.The AQWA software was used to generate ship motion data with different wave heights and periods.The ablation experiments of the im-proved sparrow search algorithm were carried out in MATLAB/Simulink software under the sea state of 4-6 PM spectrum and the gravity waves under the sea state of 6 at 90°and 180°wave direction angles.It was verified that Circle Cauchy Reverse Sparrow Search Algorithm(CCRSSA)had better effect on PID control parameter optimization.Then comparing with Genetic Algorithm(GA),Particle Swarm Optimization(PSO)and other algorithms,the results showed that the improved sparrow search algorithm had good optimization control effect and convergence speed un-der different sea conditions of 4-6 levels.Finally,compared with reinforcement learning control method,it was proved that the improved PID con-trol could achieve better compensation for ship motion and had the advantage of real-time response.4)Test verification based on the hardware platform.The comparison test between CCRSSA and PSO was carried out with hardware equipment.The length of the electric cylinder was col-lected by the enconder,and then the positive solution of the collected electric cylinder length data was calculated.The compensation results of three degrees of freedom showed that the compensation control results of CCRSSA under different sea conditions had advantages,with adaptabil-ity and generalization.Finally,compensation error and efficiency in different ship motion values were calculated.Although the compensation effi-ciency was decreased slightly with the increase of sea state grade,it was still above 95%.It could meet the needs of high precision wave compens-ation and meet the requirements of actual offshore operations.This paper mainly studies the compensation control of multi-degree-of-freedom wobble caused by irregular and regular wave movement of engineering ships in deep sea areas under class 4～6 sea conditions.From the aspects of forward and inverse kinematics analysis,modeling,control and parameter optimization,some achievements have been made.However,there are still some domains that have not been explored and studied,and the studies are needed to supplement in follows:1)In practical applications,the sea state environment is complex and changing,and the invariable compensation control system model is not suitable for the changing envir-onment.Therefore,it will be more helpful to study adaptive models under the changeable environment and carry out the hardware online test with virtual simulation platform.2)The model established in this paper is relatively complex and mainly used for the design of offline control schemes,which cannot apply some deep learning methods to online interactive learning.Therefore,it is urgent to study models that can be applied to deep learning and online control.