Research On PROFIBUS-DP Communication Test System Of Intelligent Motor Protector

The control of motor is more flexible with the rapid development of industrial automation technology. Intelligent motor protector with its powerful function, high accuracy, high reliability, and networking features becomes the the development direction of motor protector and Control field. PROFIBUS-DP is one of the most successful fieldbus technology in the world, and intelligent motor protector with PROFIBUS-DP communication function hold an important position in the market of intelligent motor protector. At present, most of the intelligent motor protector products made by domestic manufacturers can not absolutely accord with DP protocol. And the artificial way is mainly used in communication function test, whose operation is complex and efficiency is low. In order to change this situation, this paper designs a test system focus on the PROFIBUS-DP communication of intelligent motor protector, which has characteristic of high degree of automation, convenient operation, strong commonality, and so on.The paper firstly analyzes the PROFIBUS-DP key technology, and then analyzes the functional requirements of test system. The test methods focus on DP protocol consistency and communication function/performance of intelligent motor protector are designed, according to the researches on the test specification of DP and the communication functions of intelligent motor protector. At last, the hardware structure of test system is designed, and the development of PC automation test software is finished. This hardware solution based on the DP master card with open dynamic link library, makes sure that the test work is executed in the framework of DP agreement standard. A combination scheme based on digital I/O card and programmable power is designed in order to realize the function interface of test system and intelligent motor protector. I/O card is the digital I/O interface between test system and motor protector, and programmable power is used to simulate the working conditions of motor. Five kinds of different auxiliary tests slaves which can simulate fault states in the interoperability tests are designed. In order to realize general use of test system, the paper establishes a software scheme from black box testing, and user-defined function test is realized by the use of extensible markup language, which greatly enhances the applicability of this system.This PROFIBUS-DP communication test system for intelligent motor protector based on the specification of PROFIBUS-DP, whose operation is easy and popularity is strong, can help users find existing communication problems in the designs, and then help users improve the communication reliability of products. This design will facilitate the development of our countries'intelligent motor protector and the application of PROFIBUS-DP technology.