The trawler winch is a main winching tool in the fishing operation of trawler. The disturbing influence of various factors such as sea wind and waves, change in the size of the catch and the turning of the fishing vessel during the operation of the trawler will cause unbalanced force on the wire rope of the two winches, which will easily cause the deformation and damage of the fishing net facilities and directly affect the improvement of the fishing yield and increase the harvest. In order to compensate for the change of the tension of the winch tractor during the operation of the trawler, the change of the load tension caused by the wave, or the rotation direction of the fishing vessel, and to ensure the good shape of the net opening, an electro-hydraulic control technology was used to design an automatic trawler tension controller. The tension control method of the trawler is investigated. The tension sensor is used as the input information of the electrical signal of the trawler's left and right trawler, which is measured indirectly and transmitted to the controller for logical operation, and the output torque of the hydraulic motor is changed by controlling the pilot overflow, which drives the trawler winch to adjust the tension of the left and right trawler to achieve the dynamic balance of the control system. In order to solve the problem of the tension of the trawl and the influence of the length change on the trawl, we designed an intelligent control system combining PLC control system and hydraulic system and used AMEsim hydraulic simulation software system to model and simulate it, the results show that without PLC control the torque of hydraulic motor 1 is 2387.7NM, the torque of hydraulic motor 9 is 2148.64NM the difference is 239.06 NM uneven force on both sides of the trailing platform, after adding PLC adjustment torque is obviously controlled torque to maintain about 2300NM, within a certain range to play a reliable adjustment effect.

This paper introduces the rapid automatic control module of trawler based on the hydraulic system of ‘Zhejiang fishery scientific research ship No.2’.The hydraulic simulation model of double motor winch system is built in AMESim software, and SIMULINK module in MATLAB software designed closed loop fuzzy PID controller for hydraulic system simulation. through fuzzy PID control technology drives the hydraulic winch to quickly adjust the tension of the traction, maintain the stable balance of the traction force, maintain the optimization of network horizontal expansion, not only improve the fishing efficiency, but also timely and effective protection mesh. the technical achievements formed by the research will enable small and medium-sized trawlers to adjust the tension under various working conditions through the fuzzy PID control system to stabilize the opening shape of the trawl, so as to improve the automation level and fishing efficiency of related trawling equipment, and provide technical support for precision fishing.

In order to study the interaction effect between three buoys of wave power platform of "Haiyuan 1", we’ve made a research to that wave power platform in real sea conditions. We tested respectively the motion curve of different buoys, calculated the average delivered power, and analyze the interaction effect of buoys. We hope that the experimental result can provide technical support for the arrangement of wave power platform buoy.

The paper introduces the hydraulic jack-up system design about the first domestic self-installing product platform. According to the production platform features, the jack-up system chooses the mode of hydraulic cylinder driving. So the jack-up system is both economy and safe reliability. The jack-up system is equipped with proportional valve and the PLC programmable controller which has a touch panel to show the inclination of the platform, the synchronism of hydraulic cylinders in the four legs of the platform, the state of the piston pin and the alarm indication of the hydraulic power station etc.