船用柴油机压电喷油器执行器动态特性试验研究

Experimental Study on Dynamic Characteristics of Piezoelectric Injector Actuator of Marine Diesel Engines

关键词:  喷油器  驱动电压  驱动电流  温度  压电执行器  动态特性  船舶柴油机

Key words:  Injector  Driving voltage  Driving current  Temperature  Piezoelectric actuator  Dynamic characteristics  Marine diesel engine

摘要:

为探究热-电场下压电喷油器内部执行器动态特性变化规律，建立了压电执行器热-电-力多场加载动态测试系统，分析了在不同电场和热场下压电执行器的动态响应特性和位移特性的变化规律。结果表明：压电执行器响应速度随充放电过程峰值电流的增加而增加，其最大稳定位移随驱动电压增加也基本呈现线性增加的趋势，电压由100V增加到160V，最大稳定输出位移增加了约57.9%，但充放电时间有所延长；当电流超过14A，电压超过140V时变化趋势减缓；温度低于100℃时，压电执行器的最大稳定位移随温度升高基本呈现线性增加的趋势，尽管充放电过程峰值电流有所增加，但受执行器材料等效电阻和电容的变化影响，响应特性仍变差；当温度超过100℃时，由于逐渐接近材料的居里温度点，执行器输出位移急剧减小，且响应时间明显延长，不利于压电执行器的快速响应。

Abstract:

In order to explore the dynamic characteristics of the actuator of piezoelectric injector under the thermal-electrical field， a dynamic test system of the thermal-electrical-force multi-field loading of the piezoelectric actuator was established. The dynamic response characteristics and displacement characteristics of the piezoelectric actuator under different electric and thermal fields were analyzed. The results show that the response speed of the piezoelectric actuator increases with the increase of the peak current during the charging and discharging process. The maximum stable displacement increases linearly with the increase of driving voltage. The voltage increases from 100V to 160V， and the maximum stable output displacement increases by about 57.9%， while the charging and discharging time increases. When the current exceeds 14A and the voltage exceeds 140V， the change trend slows down. When the temperature is lower than 100℃， the maximum stable displacement of piezoelectric actuator increases linearly with the increase of temperature. Although the peak current increases during the charging and discharging process， the response characteristics are still poor due to the change of the equivalent resistance and capacitance of the actuator material. When the temperature is over 100℃， the actuator output displacement decreases sharply and the response time increases significantly due to approaching Curie temperature point of the material， which is not conducive to the rapid response of the piezoelectric actuator.