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Line heating is highly susceptible to plastic deformation leading to structural changes, which seriously affects shipbuilding efficiency. It is extremely important to obtain the precise line heating deformation law. There is much research on plate deformation prediction, but there is still no mature, accurate and fast prediction method. Based on this, it is necessary to research the line heating deformation prediction method. ELM has the advantages of fast learning speed, good generalization performance and strong function approximation ability. To address the poor stability of the regression model due to the randomly generated weights and thresholds of ELM, a combined prediction model (SSA-ELM) based on a squirrel search algorithm (SSA) optimized limit learning machine is proposed. The results show that the relative errors of transverse shrinkage and angular deformation of SSA-ELM are improved by 4.7% and 3.9%. The SSA-ELM prediction model has good regression accuracy and generalization ability. It gives more accurate prediction results in terms of line heating deformation prediction.

Wind power generation system has characteristics of high nonlinear and stochastic. In this paper, power control strategy of permanent magnet synchronous wind power generation system is investigated to realize power adjustment under full wind speed conditions. For the wind power generation system operating under rated wind speed, the inverse system is constructed for the nonlinear dynamic model of the system. Then, an exact linearization feedback controller is constructed to achieve maximum power point tracking. When the wind speed is higher than the rated speed, a variable pitch controller is proposed by the usage of inverse system method. A pitch angle control module is employed to ensure the rated power output and limit rotor speed. Based on the maximum wind energy capture and the constant power control, the all operating regions control of permanent magnet synchronous wind power generation system is discussed. The continuous of the controller is analyzed. Simulation results show the effectiveness of the proposed control strategy.