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Feedforward suppression of force ripple based on a simplex-optimized dither signal.

K K Tan·S J Chin·H F Dou
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Abstract

This paper presents the design and realization of a feedforward dither signal to reduce the force ripple in an iron-core permanent magnet linear motor (PMLM). A composite control structure is used, consisting of three components: a simple feedforward component, a PID feedback component, and a ripple compensator (RC). The first two components are designed based on a dominant linear model of the motor. The dither signal is generated based on a signal model which is identified using a multidimensional simplex downhill method. In this way, a simple approach is available to eliminate or suppress the inherent force ripple, thus facilitating smooth precise motion while uncompromising on the maximum force achievable. Real-time experimental results verify the effectiveness of the proposed scheme for high precision motion trajectory tracking.

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AlgorithmsFeedbackLinear ModelsModels, TheoreticalMotionQuality ControlStochastic ProcessesStress, MechanicalJournal Article

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K K Tan, S J Chin, H F Dou. 2003. Feedforward suppression of force ripple based on a simplex-optimized dither signal.. https://doi.org/10.1016/s0019-0578(07)60110-4

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