压电式推力测试系统动态性能分析与改善

姿控火箭发动机推力测试系统的动态性能对于推力测量的准确性具有重要影响.采用方形脉冲力模拟发动机推力,对压电式推力测试系统进行了动态标定,根据频响特性曲线建立了测试系统的高阶传递函数模型并获得了动态性能指标.针对测试过程中的超调和振荡,基于高阶传递函数模型,采用阻尼补偿法对推力测试系统的输出进行补偿.结果表明,经过补偿后误差减小,改善了压电式推力测试系统的动态性能.

Analysis and Improvement of the Dynamic Performance of Piezoelectric Thrust Test System

The dynamic properties of the thrust test system for the attitude control rocket motor have great influence on the accuracy of the thrust measurement. The piezoelectric thrust test system was dynamically calibrated by using square impulse to simulate the engine thrust. Based on the frequency response curve, a high order transfer function model was established to obtain the dynamic performance indexes of the measurement system. Aiming at the overshooting and the vibration occurred in the process of the thrust measurement, the damping compensation was used to compensate the output of the thrust test system, according to the high order transfer function model. The results showed that the error could be decreased by the damping compensation, and the dynamic performance of the piezoelectric thrust test system was improved.