超磁致伸缩致动器电流响应特性实验研究

Experimental study on current response characteristics of giant magnetostrictive actuator

为满足高压共轨喷油器的驱动要求,设计了喷油器用超磁致伸缩致动器。针对传统直流方波驱动响应速度慢的不足,基于大电压开启技术设计了致动器的驱动波形;分析了开启电压及其持续时间对电流响应特性的影响,确定了合理的驱动方案,并探讨了不同占空比对电流稳态值和上升时间的影响;实验研究了不同占空比和开启电压下,合理开启电压持续时间的变化规律,并对变化规律进行了拟合。结果表明,与传统方波相比,大电压开启波形能大幅缩短致动器的电流响应时间;经开启电压持续时间,电流恰能增长至稳态时,电流响应时间最短;合理的开启电压持续时间与幅值呈负指数关系,且随占空比的降低而整体下移,常数补偿的负指数函数形式可有效拟合二者关系。

For meeting the driving requirements of injector,a giant magnetostrictive actuator is designed.Current response is too slow when DC square wave drives actuators.To solve this problem,the large voltage fast opening technology was used to design the driving wave of actuator.Reasonable waveform was determined from analyzing the impact of open voltage and the duration on the current response characteristics.And the influence of different duty radios on current steady-state value and rise time was discussed.Considering the influence of different duty ratios and open voltage,change rules of reasonable open voltage duration were studied and fitted through the experiments.The results show that compared with the traditional square wave,the driving waveform based on the large voltage fast opening technology can greatly shorten the actuator current response time.And after opening duration,the current increases to the steady-state value rightly and the response time is the shortest.Reasonable duration of opening voltage has negative exponent relation with the open voltage amplitude,and decreases integrally with the declines of duty radio.And the negative exponential with compensation of the constant coefficient can effectively describe the function between the two.