动力短舱校准装置的供气流量控制策略

Flow control strategy for powered nacelle calibration facility

为了降低动力短舱校准装置的马赫数波动,提高校准数据的准确性,需要对供气流量控制策略进行研究。对系统整体特性进行了分析,对高压供气控制系统采用广义预测控制算法实现在一定时域内的最优控制,针对气源压力扰动导致的流量稳定性较差的问题,采用带遗忘因子的递推最小二乘法在线辨识扰动模型,通过扰动前馈的控制结构实现对于扰动的有效抑制。针对数字阀切换过程不同步导致的流量冲击现象,设计了一种针对数字阀的异步切换控制器来抑制该扰动。开展了某型号短舱的校准试验,结果表明:供气流量控制精度优于±0.001 kg/s,马赫数控制精度优于0.000 5,控制效率提升了40%,证明所提出的控制策略是有效的。

In order to reduce the fluctuation of Mach number of powered nacelle calibration facility and improve the accuracy of calibration data,it is necessary to study the control strategy of air supply flow rate. The overall characteristics of the system were analyzed, and the generalized predictive control algorithm was adopted to realize the optimal control of the high-pressure air supply control system in a certain time domain. At the same time, considering the problem of poor flow stability caused by the pressure disturbance of air source,the recursive least square method with forgetting factor was adopted to identify the disturbance model online,and then the disturbance feedforward control structure was adopted to effectively suppress the disturbance. Considering the problem of flow shock caused by asynchronous switching process of digital valves,an asynchronous switching controller for digital valves was designed to suppress the disturbance. Finally, calibration test of a certain type of nacelle was carried out. Results showed that the control accuracy of air supply flow was better than ±0.001 kg/s,the control accuracy of Mach number was better than 0.000 5,and the control efficiency was increased by 40%,proving that the proposed control strategy was effective.