The Research Of Doubly-fed Wind Power System Based On NI Platform

As a kind of sustainable energy,wind energy has become a mainstay of new energy which has occupied increasing proportion of power system capacity, however, growing wind power system capacity with intermittent and uncertainty characteristic of wind resources will bring to the impact and unstable problems;Strict new energy access requirements are necessary. Doubly-fed wind power system research must ensure that the balanced fesibility,tuining to unbalanced condition in order to achieve unnecessary abandoning wind power.In view of the application requirements,this paper uses NI company’s core software LabVIEW and Starsim power and power electronic simulation modeling software simulation,due to the particularity of the LabVIEW graphical expression,it’s suitable to represent the control block diagram.Starsim seamlessly combines with NI products,which is very suitable for real-time simulation.NI company’s hardware products PXI-RT high-performance processor and FPGA board platform consist of experimental system of doubly-fed wind power generation.Firstly, variable speed constant frequency doubly-fed wind power system’s basic situation under three-phase balanced and unbalanced station have been introduced.Mathematical model and corresponding targeted control strategy under ideal or fault condition have been introduced. NI’s Starsim complete DFIG power system model connected back to back PWM transformers, completing control algorithm through Lab VIEW graphical language.Secondly,we set up and analyze three-phase voltage under balanced and unbalanced condition, this paper expounds the ideal under grid voltage control strategy of DFIG and maximum power tracking implement active and reactive power decoupling control. Then, analyze the unbalanced power grid when the mathematical model of doubly-fed motor and in view of the four control target four corresponding control algorithm is put forward.Finally, DC motor simulated four kinds of common wind speed model adopting 7.5kW doubly-fed induction motor NI’s PXI-RT8108 and inside FPGA board as experimental platform. Respectively we achieved maintain DC bus voltage and ensured grid-side three phase current sinusoidal,we completed rotor-side converter and maximum power tracking grid excitation process.