一种新型变频调速系统的研究

针对目前工矿企业中高压电动机调速方式改造困难的问题,采用高-低压变频调速方式取代目前广泛使用的转子串切电阻和晶闸管串级调速方式.论述了该方式的优越性、原理及设计方法.以提升机系统为改造对象,将模糊控制用于提升机速度给定曲线跟踪的方法,并设计了单片机和变频器组成的速度闭环结构.仿真结果表明,采用模糊控制策略后系统响应速度快,稳态误差小,对环境因素等引起的参数变化不敏感,具有较强的鲁棒性.

Study on a New Frequency-variable Speed-adjusting System

According to the difficult situation of high-voltage motor speed-adjusting adaptation in industry and mine,in this paper,a method using the high-low voltage frequency-variable and speed-adjusting method is presented for replacing the rotor serial resistance and the thyristor cascade method which are widely used at present.The advantage,the theory and the design of this method are explained.It is applied to the mine hoister system and the idea using fuzzy control theory to trace the hoister system's speed curve is put forward.The speed closed-loop structure made of microcontroller and frequency-variable drives is designed.The result of simulation shows that fuzzy control method makes the system response rapid and has small steady state error.The system is insensitive to the parameters' changes and has stronger robustness.