The effective identification of the load torque is one of the key methods to improve the positioning accuracy of the position servo system, and the sliding mode observer (SMO) is a common identification method in the speed control system because of its advantages of insensitive parameters and easy physical realisation. However, the existing SMO cannot achieve high precision and high response identification of load torque in the full speed range when the motor is running at variable-speed or variable-load, which limits its application in the position servo system. Based on the analysis of the stability and the adaptive law of feedback gain coefficient, an improved SMO for adaptive identification based on adaptive control and improvement of cut-off frequency is proposed. To verify the proposed method, the dedicated simulation model and test platform are built. The results show that the proposed observer can realize the adaptive identification of the load torque under the condition of variable-speed or variable-load, and the estimation accuracy is high. The position servo system designed by the proposed observer can improve the response against load change, which is an effective method for high-precision positioning control of the position servo system with a variable-speed or variable-load.

中文翻译：

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基于改进滑模观测器的永磁同步电机位置伺服系统负载自适应辨识新方法

负载转矩的有效辨识是提高位置伺服系统定位精度的关键方法之一，而滑模观测器（SMO）由于其参数不敏感、参数不敏感等优点是速度控制系统中常用的辨识方法。容易的物理实现。然而，现有的SMO在电机变速或变负载运行时，无法在全速范围内实现负载转矩的高精度、高响应识别，限制了其在位置伺服系统中的应用。在分析反馈增益系数的稳定性和自适应规律的基础上，提出了一种基于自适应控制和改进截止频率的自适应辨识改进SMO。为了验证所提出的方法，搭建了专用的仿真模型和测试平台。结果表明，所提出的观测器能够实现对变速或变负载条件下负载转矩的自适应辨识，估计精度较高。所提出的观测器设计的位置伺服系统可以提高对负载变化的响应，是对变速或变负载的位置伺服系统进行高精度定位控制的有效方法。