建立了一种新型的全阶自适应状态观测器,提出了基于观测器的速度和定子电阻辨识方案。应用Lyapunov稳定性理论,经过严格推导得出了速度辨识自适应律;通过对两个双线性矩阵不等式的求解得到状态观测器的增益矩阵,从而克服了现有采用极点配置的自适应速度观测器存在不稳定区域的问题。在此基础上,由Lyapunov稳定性条件,在保持观测器增益不变的情况下,得到观测器的定子电阻辨识算法;通过将定子电阻的辨识值反馈,减小了定子电阻变化对系统性能的影响。在Matlab/Simulink环境下,对基于自适应观测器的无速度传感器感应电机直接转矩控制进行了仿真,并以TMS320F240为控制核心构建了感应电动机直接转矩控制系统,完成了速度辨识和定子电阻辨识实验。仿真和实验结果表明本文给出的自适应观测器在全速范围内具有良好的稳态和动态性能。
This paper presents a novel full-order adaptive state observer. An adaptive identification scheme based on the observer for speed and stator resistance is proposed. By applying the Lyapunov stability theory, the speed identification adaptive law is derived strictly. And the gain of the observer is obtained by solving two bilinear matrix inequalities. Compared to the pole-placement technique, it overcomes instability of the regular adaptive speed observer. Meanwhile, according to Lyapunov stability condition, stator resistance identification algorithm is obtained, keeping the same observer gain. The influence on the system performance is reduced by feeding back the identification value of the stator resistance. In the Maflab/Simulink environment, based on the observer, the model of speed sensorless induction motor by applying direct torque control is built. Finally, taken the microchip TMS320F240 as a core controller is built, a speed sensorless direct torque controlled induction motor drive is developed. The experiment of speed and resistance identification process is conducted. Simulation and experimental results verify that the adaptive observer possesses good static and dynamic performances in the full speed range.