The Research Of Motor Soft Starter Based On Intel 80C196MC

The Three-phase Asynchronous Motor is widely used in business, industrial and agricultural production, national defence and daily electrical equipment because of its simple structure, reliable operation, convenient maintenance and low price. With the development of modern industrial and production technology, the demand of motor starting control is becoming higher and higher. The traditional start methods are not able to satisfy the needs of industrial production, because they can't really eliminate the voltaic impact. The advent of the soft starter solves the problem; it makes the motor start smoothly, eliminates the voltaic impact and achieves a real stepless start.Combined with the high-speed processing capability of 16-bit motor control chip Intel 80C196MC and based on the theory of thyristor phased regulator, the AC motor control principle and the strategy of soft start, this article introduces an intelligent soft starter based on this microcomputer and the thyristor which is the main circuit device.First, we used MATLAB to do a system simulation and obtained the rules of current, voltage and torque under different starting modes. The result illuminated the accuracy of the tentative and laid the foundation for hardware and software design.By a large number of information finded and summarized, this article carries out on the hardware circuit design and debugging, such as thyristor synchro and triggering circuit, Intel 80C196MC external system design, current detection circuit and fault circuit protection and so on. Finally I completed the circuit confirmation and the PCB boards. Moreover, I deeply studied the soft start control algorithms and the current closed-loop, did the software programming and debugging to the voltage slope starting mode, current-limiting starting mode, voltage slope and current-limited starting mode and soft stop mode, constantly improved the control performance.The results show that the soft starter can well eliminate the current impact and complete the stepless motor start at different starting modes. The soft starter achieves the design requirements.