In-grid Performance Analysis On An 10MW Superconducting Wind Turbine

With the rapid development of the wind turbine market, there has been a trend toward increasing turbine rating. In recent years, with the more mature production technology and better performance of high temperature superconducting(HTS) material, the superconducting wind turbine becomes one of the main development directions of wind power generation technology.Firstly, the structure of the 10 MW HTS wind turbine was designed based on the analysis of the structure characteristics of HTS generators, and the design experience of HTS motors from different countries, which includes the design of the size of stator and rotor, the structural parameter setting and so on.Then, the mathematical model and the simulate model of the HTS synchronous generator were established in this paper. And the simple model of the grid system of the above 10 MW HTS generator was built based on the SimPowerSystem libraries in Matlab/Simulink, which includes the design of converter and its control system. The simple model of the grid system of the 10 MW HTS generator allows us to analyze the core operation law, including fault currents, torques and the characteristic differences between conventional and superconducting machines.Finally, the fault stator current, fault excitation current, fault torque, fault rotation speed and the maximum fault clearance time of the system were analyzed after three phase short circuit fault happened on the grid system of the 10 MW HTS generator. And these were compared with the corresponding amount of traditional synchronous generator when three phase short circuit fault also happened. The result showed that the biggest fault clearance time of HTS system is longer than that of the conventional system. The change of the field current showed that it would not have damage on superconducting magnet coil, once the protection system could act quickly to remove the fault after three phase short circuit fault happened. However, the biggest fault stator current and the biggest failure torque of the HTS system are larger than these of traditional one.It can be seen from the simulation result that the HTS generator has many disadvantages while it has lots of advantages. In this paper, a practical technical solution was put forward to improve fault shock problem, which is decreasing the thickness of damping screen of the superconducting generator. And the simulation result showed that this measure has an obvious effect on oscillation amplitude of the superconducting fault torque. The paper also analyzed the performance of the HTS generator with structure, and the result manifested that the recovery time of the structure having long-axis was longer than that of short-axis one. Furthermore, it is concluded that the light weight design can be obtained by increasing the radius of generator.