An Control System Of Flow Field In Wind Tunnel Based On High Voltage Conversion Frequency Control Method

With the development of global economy and intensifying competition in aviation industry, which have caused transform in wind tunnel experiment field. New tide of wind tunnel experiment comes out. To be on top in this area, the Occident has invested a mint of capital to update and rebuild their facility of wind tunnel, to adjust working pattern,to improve efficiency and to develop new experimental technology. Facing challenge, we have to implement collectivization tactic. Changing old wind tunnel, rebuilding new, and improve technology. All these make improving of F1-8 wind tunnel flow field system become an important problem.It is for the first time in domestic wind tunnel experiment that to adopt high voltage transducer to rebuild adjusting system of flow field of large-scale wind tunnel. This text will analyze technology requirement and realization way of flow field adjusting system of FL-8, and expatiate the theory of frequency conversion. AC variable frequency speed regulator controlled by DTC become the key technology of this facility and make it more advantage and credible. New method and tactic to control wind speed was given.FL-8 is a close single circumfluence low velocity wind tunnel. It was build by Harbin Military University. It was the first time to use 3-meter quantitative wind tunnel, which has made a great contribution to our country's space flight career and gained nice credit standing. With the development of space flight, experiment with wind tunnel became more and more. Accomplishing tasks effectively and qualitatively becomes more significant. Since the old type of FL-8 cannot meet the new requirement, we have to rebuild the control system of electromotor.Quality of wind tunnel relates not only to airflow shape and outside frame but also subjected to the control system of electromotor. The rotate speed of fans and the speed press of flow field at experimental segment are the primary parameters for control. Low speed wind tunnel experiment requires strict of the wind speed, which requires a wild range of wind speed, high precision, and quick adjustment. Besides to control rotate speed of electromotor, the control system adjusts wind speed, substantively it is the control of speed press (V2=2q/p). So, flow field control system adjusts speed press through the control of rotate of electromotor. The main primary way to do that is to enhance the feed back precision; choose excellent electromotor; adopt advantage control technology.