Analysis of pressure pulsation mechanism and dynamic characteristics of axial piston pump

ZHAO Baojian, GU Lichen, LIU Jiamin, GENG Baolong, SHI Yuan, WU Haoyu, YANG Sha

（School of Mechatronic Engineering， Xi’an University of Architecture and Technology, Xi’an 710055, China）

Abstract： The pressure pulsation of axial piston pump is not only an important cause of rotation speed fluctuation, vibration noise and output stability of the hydraulic system, but also the main information source for obtaining fault information. Hydraulic system is characterized by strong noise interference, which leads to low signaltonoise ratio (SNR) of detection signals. Therefore, it is necessary to dig deep into the system operating state information carried by pressure signals. Firstly, based on flow loss mechanism of the plunger pump, the mapping relationship between flow pulsation and pressure pulsation is analyzed. After that, the pressure signal is filtered and reconstructed based on standard Gabor transform. Finally, according to the timedomain waveform morphology of pressure signal, four characteristic indicators are proposed to analyze the characteristics of pressure fluctuations under different working conditions. The experimental results show that the standard Gabor transform can accurately extract highorder harmonics and phase frequencies of the signal. The reconstructed timedomain waveform of pressure pulsation of the axial piston pump contains a wealth of operating status information, and the characteristics of pulsation changes under various working conditions can provide a new theoretical basis and a method support for fault diagnosis and health assessment of hydraulic pumps, motors and key components.

Key words： axial piston pump； pressure pulsation； standard Gabor transform； appearance characteristics； operating conditions

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轴向柱塞泵压力脉动成因及其动态特性分析

赵宝建， 谷立臣， 刘佳敏， 耿宝龙， 石媛， 仵浩宇， 杨莎

（西安建筑科技大学 机电工程学院， 陕西 西安 710055）

摘要:轴向柱塞泵压力脉动既是引起液压系统转速波动、 振动噪声以及输出稳定性的重要原因， 也是获取故障信息的主要信息源。 液压系统具有强噪声干扰特性， 导致监测信号信噪比低， 因此很有必要深度挖掘压力信号携带的系统运行状态信息。 本文首先通过柱塞泵流量损失机理， 来分析流量脉动与压力脉动之间的映射关系。 之后基于标准Gabor变换对压力信号进行滤波重构。 最后根据压力信号时域波形形貌， 提出4个特征指标来分析不同运行工况下的压力脉动特点。 实验结果表明： 标准Gabor变换能够准确提取信号中的高次谐波及相位频率。 其重构的轴向柱塞泵压力脉动时域波形形貌， 蕴含着丰富的运行状态信息。 通过分析各工况下脉动的变化特点， 为液压泵、 马达及关键元件的故障诊断和健康评估提供了新的理论依据和方法支持。

关键词:轴向柱塞泵； 压力脉动； 标准Gabor变换； 形貌特征； 运行工况

引用格式：ZHAO Baojian, GU Lichen, LIU Jiamin, et al． Analysis of pressure pulsation mechanism and dynamic characteristics of axial piston pump． Journal of Measurement Science and Instrumentation， 2022， 13（1）： 2130. DOI： 10．3969／j．issn．16748042．2022．01．003

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