DCM模式下等离子体电源的频率控制方法设计  

Frequency Control Method Design of Plasma Power Supply in DCM Mode

作　　者：薛家祥[1] 高鹏 高喆 周钢 XUE Jia-xiang;GAO Peng;GAO Zhe;ZHOU Gang(College of Mechanical and Automobile Engineering,South China University of Technology,Guangzhou 510640,China;Dongguan Large Electronics Co.,Ltd.,Dongguan 523070,China)

机构地区：[1]华南理工大学机械与汽车工程学院,广州510640 [2]东莞市钜大电子有限公司,东莞523070

出　　处：《自动化与仪表》2022年第11期27-32,共6页Automation & Instrumentation

基　　金：国家自然科学基金资助项目(51875213);东莞市科技装备动员项目(KZ2019-6,KZ2020-01)。

摘　　要：针对材料表面改性用等离子体电源存在控制能力差、瞬时输出功率低、系统损耗大等问题,该文分析不同工作模式下电流波形对放电效果和输出功率的影响,确定采用DCM的工作模式,并设计了一种自适应频率控制方法。该控制方法通过DSP的eCAP模块捕获电流过零点,利用所得负载电流谐振频率结合DCM频率条件以及电流间断时间自适应调整全桥逆变电路的PWM周期和占空比,从而实现频率调节。实验结果表明,该控制方法不仅能够保证电路工作在DCM及ZCS状态,还能显著提升瞬时输出功率,减小系统损耗,改善材料表面改性效果。For the plasma power supply for material surface modification,there are problems such as poor control ability,low instantaneous output power,and large system loss.This paper analyzes the influence of current waveforms on discharge effect and output power under different operating modes,determines the working mode of DCM,and designs an adaptive frequency control method.This control method captures the current crossing zero point through the eCAP module of the DSP,and uses the resulting load current resonance frequency to adjust the PWM period and duty cycle of the full-bridge inverter circuit adaptively by combining the DCM frequency conditions and the current interruption time,so as to achieve frequency regulation.Experimental results show that the control method can not only ensure that the circuit works in DCM and ZCS states,but also significantly increase the instantaneous output power,reduce system loss,and improve the surface modification effect of the material.

关 键 词：等离子体电源 频率控制 DCM 全桥逆变 DSP 

分 类 号：TN86[电子电信—信息与通信工程]