Page 68 - 《应用声学》2023年第4期

第 42 卷 第 4 期 Vol. 42, No. 4
2023 年 7 月 Journal of Applied Acoustics July, 2023

⋄ 研究报告 ⋄

超声波电源中数字鉴相器设计 ∗

刘宁庄 † 龙路阳 杜光辉 段富才

(西安科技大学电气与控制工程学院 西安 710000)

摘要：超声波电源系统中电压电流相位差测量精度影响着换能器振幅稳定性以及系统工作效率。目前基于异
或门原理，采用分立数字芯片实现鉴相的方案，存在信号调理电路复杂、线性范围小、精度低等问题。为提高电
压电流鉴相精度，该文提出了一种数字鉴相器设计。该数字鉴相器采用正交解调原理鉴相，并使用坐标旋转数
字算法在 FPGA 上实现了鉴相器的设计，简化了电路，减少了杂散信号的干扰。经过 Modelsim 仿真测试表明
在 30 dB 信噪比条件下鉴相误差为 0.21 ，最后经过实验测试，数字鉴相器鉴相最大误差绝对值为 0.256 ，提高
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了测量精度。
关键词：超声波电源；正交解调；数字鉴相器；坐标旋转数字算法
中图法分类号: TN930 文献标识码: A 文章编号: 1000-310X(2023)04-0730-07
DOI: 10.11684/j.issn.1000-310X.2023.04.008

Design of digital phase detector in ultrasonic power supply

LIU Ningzhuang LONG Luyang DU Guanghui DUAN Fucai

(School of Electrical and Control Engineering, Xi’an University of Science and Technology, Xi’an 710062, China)

Abstract: The measurement accuracy of the voltage and current phase difference in the ultrasonic power
system affects the amplitude stability of the transducer and the working efficiency of the system. At present,
based on the principle of XOR gate and using discrete digital chips to realize phase detection, there are
problems such as complex signal conditioning circuit, small linear range and low precision. In order to improve
the accuracy of voltage and current phase detection, this paper proposes a design of a digital phase detector.
The digital phase detector adopts the principle of quadrature demodulation to detect the phase, and uses the
coordinate rotation digital computer (CORDIC) algorithm to realize the design of the phase detector on the
field programmable gate array (FPGA) which simplifies the circuit and reduces the interference of spurious
signals. The Modelsim simulation test shows that the phase detection error under the condition of 30 dB
signal-to-noise ratio is 0.21 . Finally, through the physical test, the absolute value of the maximum phase
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detection error of the digital phase detector is 0.256 , which improves the measurement accuracy.
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Keywords: Ultrasonic power supply; Quadrature demodulation; Digital phase detector; Coordinate rotation
digital computer algorithm; Field programmable gate array

2022-03-09 收稿; 2022-05-18 定稿
国家自然科学基金项目 (51807075)
∗
作者简介: 刘宁庄 (1973– ), 男, 陕西富平人, 副教授, 硕士研究生导师, 研究方向: SOC 嵌入式系统应用技术, FPGA 应用技术。
† 通信作者 E-mail: liuningzhuang@126.com