Research On High Voltage Narrow Pulse Equipment Control System

At present,high voltage narrow pulse equipment is widely used in the fields of sterilization and dust removal,but the simple equipment and backward control system cannot meet the industrial demand.Therefore,it is imperative to develop a powerful,reliable and convenient high voltage narrow pulse equipment.In order to ensure the stable operation of equipment and reduce human intervention,advanced control system is essential.This paper mainly describes high voltage narrow pulse sterilization key technology and its control system.Main research work and innovation points are as follows:(1)Mechanism of pulse sterilization is analyzed.The principle of killing microorganism by pulse is analyzed by the theory of electroporation and disintegration.mathematical model of sterilization efficiency is analyzed to obtain that the higher electric field intensity is,the lower the microbial residual activity is.This paper also analyzes the influence of high voltage narrow pulse on sterilization and it is found that the lower pulse width is,the higher available pulse voltage is,the higher sterilization efficiency is and the performance of bipolar square wave pulse is better than others.(2)Hardware system of high voltage narrow pulse sterilization equipment is designed independently.By simulating the operation process of the pulse power supply,it is found that the inductive reactance should be reduced as much as possible to cut down the rising edge of the pulse and improve the quality of the pulse.The actual power supply circuit is built and the pulse drive and voltage control circuit are designed.Low voltage power supply,detection system,pumping system,spark signal acquisition system and 4G networking circuit are also devised.(3)For the high voltage breakdown spark,the feature extraction of spark signal is realized by wavelet analysis and FFT.And High precision recognition of high voltage breakdown spark is realized by SVM algorithm and recognition accuracy is up to 96%.Then a dynamic breakdown spark tracking control method based on spark strength is proposed to realize the pulse voltage feedback regulating.This paper used formula derivation and numerical simulation to verify that this method compared with traditional spark control has higher average voltage in the control process.Moreover,a method of regulating voltage which the conduction angle of the thyristor is used as a parameter to calculation in the algorithm is put forward so that optimizing algorithm and improving calculation efficiency.(4)High voltage narrow pulse equipment monitoring system software is designed independently.Equipment process control,4G communication and dynamic breakdown spark tracking control are realized by using android IPC.Acquisition,analysis and recognition of spark signal are realized by DSP.The deployment of daemon and the design of storage table are completed on self-built cloud server.Remote monitoring system include different user privileges is designed on WeChat Applet.Reliable private communication protocol is formulated for various communication modes.Self-designed monitoring system of high voltage narrow pulse equipment contains digital adjustable pulse power supply,monitoring equipment parameters in real time,dynamic breakdown spark tracking control,pulse voltage feedback regulation,data cloud backup,remote monitoring and other functions.This system has the advantages of high automation,friendly human-machine interface and high safety.