Study On The Wind Turbine Variable-pitch Control Strategy

Today all kinds of non-renewable resources increasingly exhaust, so development of green, non-polluting renewable energy is the most effective way to resolve the world’s energy problems for many countries. Because the wind power is such endless and repetitive use new energy, it will inevitably become the darling of all countries to pursue. At present, wind turbine is in transition phase from fixed pitch to variable pitch in China, so the study of variable pitch wind turbine control and theory is very necessary.Firstly, the principle of variable-pitch wind turbine aerodynamics is studied and explained in this article. The current most widely used two wind energy utilization factor formulas are studied in comparison by Matlab simulation software, and the better one is used in this article. The control process of variable pitch is studied. At the same time, the popular variable speed variable pitch wind turbine at present is also explored, and the overall wind turbine control strategy are derived. Secondly, the corresponding mathematical models of every part of wind turbine are built according the principles of locals composition the whole, the overall validation local. And then we establish the whole wind turbine system model. The non-controller system is simulated to prove the correction of the model. Based on non-controller model, the system is joined the traditional PID control strategy and simulated, but the results shows that traditional control strategy does not achieve satisfactory results. According to the characteristics of wind power system, fuzzy control of intelligent control mode is applied in the system. Different conditions in high speed and low speed wind, we design two fuzzy controllers respectively, simulate fuzzy control process of the system, and the result achieves the expected effect. At last, because the most wind turbines are often in very bad working environment, which requires that the controller must have higher reliability, etc. The PLC controller can satisfy the wind turbine control requirements for better. In this paper, I choose SIEMENS Programmable Controller S7-300 to design the variable pitch wind turbine control systems. According to the control flow charts of before and after into the power net for wind turbines, we complete the hardware configuration and software program for the control system in STEP7, and debug the program by S7-PLCSIM simulation software. The communication is connected between WinCC and Matlab based on Dynamic Data Exchange.