Analysis And Control Of Float-type Wave Power Generation System With PMSM

The global energy crisis makes lots of countries in the world do the research ofnew energy methods and national sustainable energy development strategy. Oceanenergy is an important renewable energy, it is estimated that the marine energyaccounts for about70%of the world’s total energy. Countries around the world arecompeting for marine resources.Our country is an ocean state so that we can abundantly take advantage of thewave energy. As a national science fund project, the paper studied a new float-typewave power system based on the analysis of the research of wave power technology athome and abroad. The system can generate electrical power and supply the pharos,residents, island military preparedness, and so on. And when the technology is mature,the large-scale grid-connected power generation can also be realized. So thisinvestigation has an important theoretical and practical meaning.The float-type wave power generation device capture wave power by the floatand transfer the energy through the mechanical transmission devices, so the waveenergy can be finally converted into electrical energy by using the permanent magnetsynchronous generator (PMSG) and its control system. The float-type wave powergeneration system is studied in this paper, and the work is mainly as follows:(1) The principles, anchoring methods and control strategies of wave powergeneration systems are introduced with the development of wave power technology athome and abroad described.(2) A new float-type wave power generation system is put forward with its waveenergy converter fully studied. The analytical force analysis and calculation of thefloat based on Froude-krylov theory is carried out. And the force analysis is alsosimulated and verified by using MATLAB software.(3) The low speed PMSG in the system is designed, and the electromagneticdesign process is given. The numerical calculation and simulation verification of thePMSG is carried out using finite element analysis in ANSOFT software. Thesimulation results show that the parameter characteristics are in accordance with thedesign scheme.(4) The simulation models of islanding power generation and grid-connection are built. The corresponding voltage and frequency control strategy and low voltage ridethrough (LVRT) method based on PR control are designed. According to the wavecharacteristics in the coastal area in Tianjin, the system output performance under twodifferent conditions are simulated. The simulation results verified the accuracy of thecontrol methods.