The Basic Theory Research Of HTS Wind-turbine Generator And Simulation Analysis

With the development of HTS materials technology recently, the basic theory researches on HTS electrical machine have attached great importance from some international research organizations and institutes, and some problems appeared in the design and theory studies on the HTS electrical machine. This paper is based on the HTS wind generator theory, with the FEM simulate software, designed a HTS permanent magnet synchronous generator. Moreover,analyzed and summarized the reason and solving method of AC loss in the HTS electrical machine. Then, it is proposed a method to solve the AC loss and some conclusion analysis of the Preliminary simulation has been shown.Firstly, this paper studied the development state of the HTS materials which is applied in HTS generator design and summarized some HTS theory model. Then, the theory of the HTS model and the design theory of HTS electrical machine has been analyzed and summarized.On the basis, according to the strong magnetic properties of HTS bulks, a 3MW half-superconducting HTS permanent magnet synchronous wind generator has been designed.The HTS model has been confirmed and simulated in the FEM static electromagnetic field.Due to HTS generator model in FEM, it has been simplified firstly. Then, under the liquid Liquid nitrogen situation, the HTS generator electro-magnetic has been tested and the effectiveness has been proved. Through the result of the simulation which compared in the same size, HTS electrical machines are with advantages of small loss, high efficiency, good operating adjustment performance.Secondly, according to the researches and analyses of AC loss, the reason and some solving method has been shown. And there is shown a new method to avoid or reduce the AC loss. Though changing the structure of the electrical machine, the AC loss could be avoided by using the method of armature to be DC. Based on Faraday’s electromagnetic induction law,a improved model has been proposed. Through FEM 3D analysis, the hypothesis model of stable direct current in the conductor has been achieved, and verified the permanent magnet magnetization and the feasibility of the magnetic path in theory.Finally, compared with simulated experiment and traditional electrical machine theory, a full-superconducted HTS DC electrical machine has been designed and modeling by FEM software. In this new scheme, the excitation part could be achieved by permanent magnet which has the same polarity in radial direction. A cage bars structure in stator is designed as the armature windings. Then, through the magnetic circuit design, the electromagnetic induced current should be direct current in the armature windings. Therefore, when the HTS material is used in the armature windings, the AC loss could be avoided. Meanwhile, we can use the HTS bulk which has the characteristic of strong magnet field to take place of the permanent magnet in the part of excitation. In this way, it can overcome the existing drawback and considerably improve the efficiency of full-HTS electrical machine.