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As a key component to adjust the speed and torque, double-fed speed up gearbox plays a vital role in reliability and stability for the wind turbine system. Considering the base helix angle, normal pressure angle, position angle, rotation of carrier and the mesh of the ring gear and planet gear, a coupled dynamic model for high-power wind turbine gearbox transmission system, which consists of two helical planetary stages and one helical gear stage was established using the lumped parameter method in this paper. Numerical integration applying the explicit 4/5th order Runge-Kutta algorithm was used to solve the proposed model and the dynamic responses of transmission system were investigated. Results show that the modal frequencies for the system are not coincided with the gear mesh frequencies of the stages. Then, the dynamic mesh forces of the 1 st stage in different models are compared and analyzed in frequency domain.

Target detection and segmentation algorithms have long been one of the main research directions in the field of computer vision, especially in the study of sea surface image understanding, these two tasks often need to consider the collaborative work at the same time, which is very high for the computing processor performance requirements. This article aims to study the deep learning sea target detection and segmentation algorithm. This paper uses wavelet transform-based filtering method for speckle noise suppression, deep learning-based method for land masking, and the target detection part uses an improved CFAR cascade algorithm. Finally, the best separable features are selected to eliminate false alarms. In order to further illustrate the feasibility of the scheme, this paper uses measured data and simulation data to verify the scheme and discusses the effect of different signal-to-noise ratio, sea target type, and attitude on the algorithm performance. The research data show that the deep learning sea target detection and segmentation algorithm has good detection performance and is generally applicable to ship target detection of different types and different attitudes. The results show that the deep learning sea target detection and segmentation algorithm fully takes into account the irregular shape and texture of the interfering target detected in the optical remote sensing image so that the accuracy rate is 32.7% higher and the efficiency is increased by about 1.3 times. The deep learning sea target detection is compared with segmentation algorithm, and it has strong target characterization ability and can be applied to ship targets of different scales.