基于模糊PI算法的频率自动控制系统设计

Design of frequency automatic control system based on fuzzy pi algorithm

分析了超声换能器频率相位差和偏移值的关系,由于无法通过时域模型来表达,并且该模型构建的经典控制器其适用性不高,基于此本研究提出基于模糊PI控制的超声电源频率跟踪系统,进一步指出换能器两端电流电压时域模型,通过频谱分析法能够获得两者相位差以实现超声电源频率跟踪仿真分析。构建超声电源频率跟踪系统并进行仿真分析,处于正常工作电压下测量初始谐振频率,通过仿真分析和实验数据表明该方法的有效性。本研究发现,相对传统控制方法来说,基于模糊PI法能够提升系统控制精度,以提升超声换能器的使用寿命以及运行效率。

This paperanalyzed the relationship between the frequency phase difference of the ultrasonic transducer and the offset value.Considering the fact thatthe classic controller constructed bythe time domain model has not high applicability,this research proposed a frequency tracking system of ultrasonic power supply based on the fuzzy PI control.Also,a time-domain model for molding the current and voltage at both ends of the transducer was presented.The phase difference between the two can be obtained by spectrum analysis methodandthe simulation analysis of ultrasonic power frequency trackingcan bemade.The ultrasonic power frequency tracking system was constructed and analyzed.The initial resonance frequency wasmeasured under normal working voltage.Simulation analysis and experimental data showed the effectiveness of the method.This study found that compared with the traditional control method,the fuzzy PI method can improve the control accuracy of the system,and consequently it can improve the service life and operating efficiency of the ultrasonic transducer.