Abstract: In order to suppress the influence of inertia disturbance on a high performance servo drive system, the system should possess the function of inertia identification and self-tuning of controller parameters. Among them, identifying the real-time inertia value accurately and rapidly should be solved first as the key. Research on inertia identification is conducted in this paper, which derives an inertia identification gradient formula of the permanent magnet synchronous motor (PMSM), and analyzes factors influencing the convergence time and precision of inertia identification. Simulation and experiments demonstrate that the gradient algorithm is effctive. The convergence time of identification is short and it can be limited to around five seconds.The shorter the period and the larger the given range of a given velocity, the better is the real-time property of inertia identification. This study can provide basis for the parameter self-tuning of the speed controller.

Key words: high performance, permanent magnet synchronous motor, servo system, inertia identification, gradient methods, identification performance