Page 25 - 《应用声学）》2023年第5期

第 42 卷 第 5 期 Vol. 42, No. 5
2023 年 9 月 Journal of Applied Acoustics September, 2023

⋄ 研究报告 ⋄

步进追频及恒振幅控制的超声电源设计

苏含玉 安纯尧 刘建停 李喜峰 †

(上海大学 上海 200040)

摘要：针对超声金属焊接过程中出现的负载变化导致谐振频率漂移和焊接振幅失恒问题，设计了一种基于步
进追频及恒振幅控制的超声电源。在负载变化对谐振频率影响的研究基础上，根据可编程逻辑阵列 -直接数字
式频率合成器步进追频原理设计了负载变化追频逻辑；结合全桥逆变电路的移相控制方式，研究了不同占空
比下的最大输入电流与最大焊接振幅的关系，提出了基于输入电流反馈下的步进移相恒振幅控制方案。实验
结果表明，负载变化追频逻辑实现了谐振频率快速变化下的动态实时追踪，解决了因频率失谐导致的焊接振
幅非线性下降问题。同时，在加入了振幅闭环控制后，实现了焊接振幅相对极差稳定在 10% 以内。
关键词：步进追频；恒振幅控制；超声电源
中图法分类号: TN86 文献标识码: A 文章编号: 1000-310X(2023)05-0917-06
DOI: 10.11684/j.issn.1000-310X.2023.05.003

Ultrasonic power supply design based on FPGA-DDS stepping

frequency tracking technology

SU Hanyu AN Chunyao LIU Jianting LI Xifeng

(Shanghai University, Shanghai 200040, China)

Abstract: Aiming at the problems of resonance frequency drift and weld amplitude loss caused by load changes
in ultrasonic metal welding, an ultrasonic power supply based on step chasing and constant amplitude control
is designed. Based on the study of the effect of load change on resonant frequency, the load change tracking
logic is designed according to the principle of field programmable gate array step chasing, and the relationship
between the maximum input current and the maximum weld amplitude under different duty cycles is studied,
and the step-shift phase constant amplitude control scheme based on input current feedback is proposed. It
solved the problem of nonlinear decrease in weld amplitude due to frequency detuning. At the same time,
after adding the amplitude closed-loop control, the relative amplitude of the welding amplitude is stabilized
within 10%.
Keywords: Step chasing frequency; Constant amplitude control; Ultrasonic power supply

2022-05-10 收稿; 2022-05-30 定稿
作者简介: 苏含玉 (1995– ), 女, 江苏连云港人, 硕士研究生, 研究方向: 超声焊接电源。
† 通信作者 E-mail: lixifeng @shu.edu.cn