By using the Lyapunov stability theory,the gain of the observer could be obtained by solving a linear matrix inequality(LMI) in Matlab LMI toolbox,which solves the unstable problem of the adaptive speed observer using pole-placement technique.

• 应用Lyapunov稳定性理论,观测器的增益借助于Matlab中LMI工具箱求解一线性矩阵不等式得到,它解决了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。