Design Of Precise Air Conditioning Fan Controlle Rbased On DSP

In order to ensure the reliable operation of the electronic information equipment, we need to provide higher standards of temperature and humidity. So precise air conditioning has a widely development, as a key part, fan control technology becomes a hot research topic.Now three-phase asynchronous motor is widely used in the precision air conditioning fan, it has many speed control methods, the most widely used is the frequency control, but frequency control has many problems, and limited on many occasions, especially in the electronic information equipment production and R&D sites. In this case researchers often use any other control methods, such as variable voltage speed control, its electromagnetic interference can be controlled more easily at power frequency, and the fan controller used this mode has simple structure, low cost, so it has a wide range of applications.There are many ways in variable voltage control circuit, through the various considerations and schemes comparison, determine the appropriate way, and then determine the whole system. The main circuit uses three-phase three-wire-free neutral point connection, and uses Freescale’s56F8025chip as the main control chip, including zero-crossing detection circuit, current detection circuit, temperature detection circuit, data storage unit man-machine interface. Main circuit and control circuit make up the whole hardware parts.Based on the above hardware circuit, in the CodeWarrior Development Studio, the software part was designed. Software including motor operating procedures and the motor running control procedures, which the motor runing control program uses three-phase power zero-crossing as a reference point, use the motor power factor angle as feedback quantity, realize the control of the fan, including the speed control and protection measures, and the motor running control program mainly including silicon controlled temperature detection, man-machine interface, the communication interface, etc.Through the experiment test, this precision air conditioning fan controller, realized the fan linear smoothing adjustment, and be able to make the appropriate protective measures in a timely manner in which they appear abnormal. The experiment conducted a comprehensive test voltage and current waveforms, and many other data when the motor work. The results show that the use of the system control fan operation when the noise is far less than similar controllers, and has good market value.