Research On Technology Of Hydraulic Individual Blade Pitch Control For Horizontal Axis Marine Current Turbine

With the development of social economy and consumption of traditional energy,the horizontal axis marine current turbine(HAMCT)has gained more and more attention as a new type of energy technology.At present,the domestic HAMCT technology is in a high-speed development stage.The power of the test prototype Level has been toward the megawatt level.However,with the enlargement of the HAMCT,the load conditions are much more complicated,so the technology of individual pitch has important research significance as the key technology of the active power and load control.In this paper,a hydraulic individual variable pitch system and pitch control strategy are designed for the 60 kW horizontal axis marine current turbine.The chapters of the thesis are as follows:The first chapter expounds the research background of this paper,introduces the research progress of marine current turbine.Then through the introduction of the research status of marine blade pith technology,the research significance and main research contents of this paper are put forward.The second chapter introduces the principle of pitch control,analyzes the theory of pitch load calculation and the pitch control process,and finally puts forward a design of individual blade pitch system according to the design requirement of 60 kW turbine.The third chapter expounds the design of mechanical structure of the individual blade pitch system,illustrates the design basis of the support structure,the oscillating cylinder and the seal structure,and verifies the feasibility of the design by the virtual assembly and finite element analysis.The fourth chapter expounds the design concept of the hydraulic system,and proposes a positioning servo control method based on speed feedback correction to restrain the influence of the load fluctuation through the theoretical analysis.The fifth chapter analyzes the operating data of the 60 kW turbine sea trial,and then proposes the individual pitch power and load control strategy based on the pitch control process and the principle of less variable pitch.The last chapter summarizes the work of the whole paper and points out aspects that deserve further research.