An Exploration into the Monitoring Methods for Key Parameters of Servo Drive Unit Based on Control Chart Method

In this study, the key parameters of servo drive units in CNC machine tools were explored by the online condition monitoring and reliability modeling during their long-term operation, in an attempt to eliminate the thorny problems in the reliability monitoring and evaluation of such servo drive units. Specifically, the model reference adaptive system algorithm was adopted to identify the online parameters of the motor by monitoring the stator resistance, stator inductance and flux linkage of the permanent magnet synchronous motor. Moreover, the percentage-based control chart was plotted to present the distribution of unknown parameters, with the intention of analyzing the reliability changing trend of the motor. Finally, the effectiveness of this method was validated via a case test. These findings contribute to the health monitoring and reliability evaluation of such servo drive units.