燃气发生器二自由度H∞自适应压强控制研究

2-Degree-of-Freedom H∞ Adaptive Pressure Control of Gas Generator

关键词:  二自由度H_∞控制  自适应控制  LPV系统  增益调度  燃气发生器  最小二乘辨识

Key words:  2-degree-of-freedom H_∞ control  Adaptive control  LPV system  Gain schedule  Gas generator  Least square identification

摘要:

为了解决由滑动板调节角度和空腔自由容积引起的燃气发生器压强时变特性的控制问题，设计了二自由度H_∞自适应控制器。首先，建立燃气发生器数学模型，并提出根据标准二阶线性模型建立燃气发生器归一化线性变参数（LPV）系统的方法。其次，假设燃气发生器系统固有频率不变，通过最小二乘辨识方法获得在不同工作点的虚拟阻尼系数分布。再其次，针对归一化LPV系统，设计了两个胞点的二自由度H_∞控制器，在两个控制器胞点之间，根据虚拟阻尼系数实时求解控制参数。最后，给出了二自由度H_∞自适应控制器输入信号量纲变换方法。仿真结果表明，燃气发生器LPV系统辨识精度高，二自由度H_∞自适应控制器具有不超调、快速控制特性和良好的抗噪声干扰能力。

Abstract:

In order to work out the control problem with time-variant characteristic of gas generator pressure， which was caused by sliding plate regulation angle and cavity free volume， a 2-degree-of-freedom H_∞ adaptive controller was designed. Firstly， the mathematical model of gas generator was established， and on the basis of standard second order linear model， method of establishing normalization linear parameter varying （LPV） system of gas generator was proposed. Secondly， assuming that the natural frequency of gas generator system is constant， the virtual damping coefficient at different working points was obtained by the least square identification method. Thirdly， aiming at normalization LPV system， two 2-degree-of-freedom H_∞ controllers were designed， between which the control parameters were solved in real time by virtual damping coefficient. Finally， the dimension conversion method of input signal of 2-degree-of-freedom H_∞ adaptive controller was proposed. The simulation results show that gas generator LPV system has high identification accuracy， and 2-degree-of-freedom H_∞ adaptive controller has characteristics of fast control with no overshoot and good anti-noise capability.