Development And Research Of Asynchronous Motor Intelligent Protection Device Based On DSP

Asynchronous motors play a very important role in modern industrial production and life.Because it often works in the environment of high temperature and humidity,which leads to frequent failures.Once the motor failure,will not only produce a very large economic losses,and even cause personal injury to the staff.In order to solve this problem,this paper aims to develop a set of intelligent motor protection device with high reliability and perfect function.First of all,this paper is to study the current status of the development of motor protection devices,and the rapid development of digital signal processing technology background,to replace the traditional form of motor protection and ensure the safe and reliable operation of the motor for the purpose of using DSP + MCU dual CPU composed of motor protection device program,selected with a strong computing power TMS320F2812 DSP as the main controller,and with the control of good performance of the microcontroller.Then,this paper uses the symmetrical component method to analyze the fault characteristics of the motor,and introduces the principle of motor protection,and builds the simulation model by Matlab software to complete the simulation of different faults.In the hardware part,the design of the whole circuit is completed,and the DSP core board based on TMS320F2812 is designed,including the signal conditioning circuit,the minimum system,external expansion Flash and RAM,communication module and so on;Single chip microcomputer as the core of the human-computer interaction board,the main device to achieve the keyboard input,LCD display and the host computer communication module,etc.There are also a current transformer module and a voltage transformer module for achieving primary to secondary signal conversion.The software part completes the main program,data acquisition and processing program,the protection of the judge program and the design of human-computer interaction program.The full-wave Fourier algorithm with a certain filtering capability is used to quickly calculate the parameters and logic judgments,and finally realize the protection function.In addition,based on the design of the Matlab GUI PC monitoring interface,real-time monitoring of the operation of the motor.Finally,the performance of the protection device is tested by the AT-900 integrated automation system,including the protection of overload,phase failure,phase short circuit,three-phase unbalance and so on.The results of the final experiment show that the design scheme has good feasibility,the device can correctly judge the fault correctly and meet the design requirements.