电控单体泵高压油路压力波动频率计算方法研究

Frequency Calculation Method Research of Pressure Oscillationin Electronic Unit Pump

喷油系统喷油过程中高压油路燃油压力波动会直接影响系统循环喷油量的稳定性和一致性。应用类比思想,引入了液力电容和液力电感概念,基于电控单体泵喷油系统的结构参数,建立了用于计算系统高压油路压力波振荡频率的LC液力系统数学模型。计算结果表明:系统高压油路中压力波的一阶振荡频率为52.3～58.1kHz,随着喷油时间的增加而增大;二阶振荡频率为454～467kHz,随着喷油时间的增加而减小;三阶振荡频率为509～593kHz,随着喷油时间的增加而增大。通过对比试验数据,验证了所建立的数学模型能够准确计算系统高压油路内压力波的振荡频率。

Pressure oscillation in high pressure circuit of Electron-Controlled Unit Pump （EUP） during injection process affects injected delivery uniformity and stability. Introduced concepts of hydraulic C and hydraulic L by analogy with electrical LC oscillation circuit, the hydraulic LC mathematical model for analyzing the pressure wave oscillation frequency in the high pressure circuit was built up based on EUP injection system structural parameters. Results calculated by using the model show that its first order oscillation frequency in range from 4.54×10^5 to 4.67×10^5 Hz rises with injection time increase; the second order one in range from 4. 54×10^5 to 4. 67×10^5Hz declines with injection time decrease; the third order oscillation frequency in range from 5. 09×10^5 to 5. 93×10^5Hz, rises with injection time increasing. Comparison of the calculation results with the test bench data demonstrates that the model is proved to be satisfactory.