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arXiv · 2305.08737

Dirty derivative stability in the frequency domain

Simon Kuang
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Abstract

Differentiation filters can be made proper by composition with a first-order low-pass filter at a desired bandwidth, resulting in a "dirty derivative." A stable closed-loop system that relies on output derivatives remains stable when the derivatives are replaced with dirty derivatives of sufficiently high bandwidth. I prove and generalize this fact by a frequency-domain argument.

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Simon Kuang. 2023-04-22. Dirty derivative stability in the frequency domain. https://arxiv.org/abs/2305.08737

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