Digital H∞ filter design for a low frequency multiple‐input multiple‐output system with multirate measurements

• Published in: International journal of robust and nonlinear control Vol. 32; no. 9; pp. 5184 - 5199
• Main Authors: Yang, Hongjiu, Wang, Shuaiying, Li, Peng
• Format: Journal Article
• Language: English
• Published: Bognor Regis Wiley Subscription Services, Inc 01.06.2022
• Subjects: Asymptotic methods; digital filter; Filter design (mathematics); H-infinity control; H∞ filter; Low frequencies; low frequency; MIMO system; multirate measurements; Samplers
• ISSN: 1049-8923; 1099-1239
• DOI: 10.1002/rnc.6081

In this article, a digital H∞ filter is designed for a low frequency multiple‐input multiple‐output (MIMO) system with multirate measurements from multiple samplers. A delay compensation is introduced to reduce estimation errors from the multiple samplers and a zero‐order holder. A single‐rate error system is obtained by converting the low frequency MIMO system using a discrete‐time lifting technique. A digital H∞ filter is proposed based on a delay‐partitioning method to guarantee asymptotic stability and H∞ performance for the single‐rate error system. A numerical example is provided to show effectiveness and superiority of the digital H∞ filter in low frequency domain.