The Design Of Intelligent Motor Protector Based On ARM

The motor as a kind of driving machine, is widely used in the power plants and industrial enterprises, and it plays a decisive role in the national economy. So it is very important to ensure the normal operation of the motor. With the development of microelectronic technology and the rapid development of computer technology, the intelligent motor protector emerged as the times require, its feasibility strong, easy maintenance, low price, and have been widely used in modern industrial applications. Therefore, it is an important subject to strengthen the design of intelligent electric protector in the present age.In this paper, the theoretical analysis on the fault operations of the electromotor is carried out firstly. The fault operations include overvoltage, overload, loss of phase, over current, three-phase unbalance fault, and so on. And research the protection principle of the fault motor, then based on the analysis of the principle of protection of the designed an intelligent motor protector. The protective device adopts the embedded ARM microprocessor as the core chip in the hardware design, uses the ADE7758 chip to complete the A/D conversion of three-phase current and voltage, the calculation of the power, reduce the hardware circuit design, and complete the man-machine exchange through the keyboard and LCD. In the aspect of software design, using C language program to achieve the real-time detection of motor running state, the fault diagnosis and display function, we add the password input function in parameter modification, to prevent the misuse of the operating personnel, we add the accident record inquiry function in display. At the same time, the motor uses ModBus-RTU protocol to complete the communication of the upper and the lower machine. The whole process enables operators to run on the motor of online monitor and remote control, and may be provided to improve fault diagnosis scheme according to the help of powerful computer network resources in the future. In addition, we studied the anti-interference design of intelligent motor protector in the aspect of hardware, software.