Research On The Experimental System For Variable-speed Constant-frequency Wind-power Generation

With the shortage of the fossil fuel such as coal, oil and the environment pollution caused by the combustion of fossil fuel, It is of great significance to develop and utilize wind power, which is not only renewable but also without pollution. Now many kinds of technologies applied to wind-power generation are in the ascendant, among which the technology of variable speed and constant frequency (VSCF) is getting increasing recognition for its characteristic of high-efficiency and practicability. And the technology also becomes research hotspot of many countrys' scholar.In this paper, it brought forward the method of emulating wind turbine by squirrel-cage induction motor to solve the prime motor issue for the study of wind power generating system in lab. And the torque-rotating speed characteristic of wind turbine is simulated by using polynomial fit. So the wind torque can be calculated under any rotating speed of wind turbine and wind speed, which is regarded as torque reference to control the inductance motor. Under the torque control, the inductance motor outputs determinate torque and rotating speed to simulate the real wind turbine.The reliable and integrated laboratory experimental platform of wind power generation system was constructed in this paper. And the platform including three converters and three DSP controllers and two squirrel-cage induction motors. The induction motor that simulated the wind turbine characteristic and the wind generator are controlled by the slip-frequency method. And the module software is written by 16 bits fixed-point C code that interfaces with assembly language functions so that it can be amended and replanted easily.Finally, a series of experimental study are done on the VSCF wind power generation system platform. The study includes the operation experiment of simulated wind turbine and wind power generation system connecting to grid conditions experiment. The result of the experiments all validated the validity and feasibility of the model of VSCF wind power generation system platform in the lab .