Design And Realization Of University Electric Machines Experimental System Based On Distributed Control

Electric machine experimental teaching can not be ignored in strong electrical courses in domestic universities.Experimental teaching and training can enable students to understand the working principle and basic features of the DC generator,DC motor,induction motor and synchronous generator more clearly.Furthermore,ability of engineering practice which includes electric machine selection in applications and debugging and troubleshooting can be improved.For now,most teaching equipment developed by domestic manufacturers has some shortcoming which can not be accepted by electric machine experimental teaching,for example,complex operation,higher failure rate caused by control circuit protection,low test accuracy and lacking of digital measurement and communication which leads the teacher cannot monitor and manage the experiment uniformly.For the above,an idea that makes the distributed control method into the electric machine experimental system design was given.The computers were divided into teacher computers and student computers.The student computers were responsible for decentralized control to the motor experimental bench,and the teacher computer was responsible for centralized management and warning.The electric machine experimental bench took single chip as the core of motor physicals collection system which can achieve high-precision measurement of voltage,current,power,power factor and speed.Student computers with application software were designed for student to realize the data communication with the electric machine physicals collection system,and can reflect the change process of the electric machine parameters accurately.Teacher computer was designed for teacher who was responsible for the management,and unified control.The computer can contact with multiple student computers to send commands and receive data.It enabled teacher to monitor and control the electric machine experimental bench,the experimental data can be managed and analyzed,and the analytical results about the student experimental status were provided for the teacher.Electric machine experimental system application software for both teacher and student were developed based on VC++ and SQL Server database.The software integrated several functions,such as data reports,graphics curve fitting and printing.Refer to the electric machine theory,several fitting algorithm of the electric machine characteristics werestudied and improved,and the rationality of result was demonstrated.The experimental system can support a variety of electric machine experiment including DC generator,DC motor,induction motor,synchronous generator and transformer in domestic universities.It has received the lab teacher's popular acclaim.