An analysis of the effects of closed-loop commutation delay on stepper motor control and application to parameter estimation

作者：Krishnamurthy Prashanth^*; Khorranti Farshad

来源：IEEE Transactions on Control Systems Technology, 2008, 16(1): 70-77.

DOI：10.1109/TCST.2007.899724

• delay effects
• motion control
• motor commutation
• parameter estimation
• stepper motors

The purpose of this brief is to call attention to a phenomenon that is observed when a closed-loop commutation delay is present in stepper motor control applications especially involving high-speed precision motors, e.g., precision assembly, wafer probing, coordinate measuring machines. Commutation I'S a popular technique used to feedback linearize the mechanical dynamics of a stepper motor by generating phase currents based on the sine and cosine of the relative position within a toothpitch. In the presence of a time delay in the closed loop, the feedback linearization is not exact and a residual term depending on incremental position remains in the closed-loop dynamics. In this brief, we show that a time delay in the closed loop results in two dynamical phenomena, viz., introduction of multiple solution trajectories with sensitive dependence on initial conditions (possibly yielding steady-state velocities with opposite signs) and saturation of velocity. We also show that these phenomena can be exploited to estimate parameters such as closed-loop delay, sensor offset, and toothpitch of the motor.

• 出版日期2008-1
• 单位香港理工大学