{"title":"Negative imaginary lemmas for improper descriptor systems","authors":"Xiaolu Liu , Meiqi Gao , Liu Liu , Naifeng Gan","doi":"10.1016/j.jfranklin.2025.107690","DOIUrl":null,"url":null,"abstract":"<div><div>This paper studies the negative imaginary property for improper descriptor systems. Firstly, it is demonstrated that a descriptor system with a negative imaginary transfer function cannot be impulse-free, that is, the negative imaginary transfer function is improper. Then some necessary conditions and sufficient conditions are established to characterize the negative imaginary property of improper descriptor systems based on the quasi-Weierstrass form. Furthermore, the lossless negative imaginary property of improper descriptor systems is derived by the relationship between the lossless positive realness and the lossless negative imaginariness. Several examples are given to illustrate the obtained results. In addition, this paper presents a generalized Kalman–Yakubovich–Popov lemma for the negative imaginary property of descriptor systems, which is achieved independently of the relationship between positive realness and negative imaginariness.</div></div>","PeriodicalId":17283,"journal":{"name":"Journal of The Franklin Institute-engineering and Applied Mathematics","volume":"362 8","pages":"Article 107690"},"PeriodicalIF":3.7000,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of The Franklin Institute-engineering and Applied Mathematics","FirstCategoryId":"94","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0016003225001838","RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"AUTOMATION & CONTROL SYSTEMS","Score":null,"Total":0}
引用次数: 0
Abstract
This paper studies the negative imaginary property for improper descriptor systems. Firstly, it is demonstrated that a descriptor system with a negative imaginary transfer function cannot be impulse-free, that is, the negative imaginary transfer function is improper. Then some necessary conditions and sufficient conditions are established to characterize the negative imaginary property of improper descriptor systems based on the quasi-Weierstrass form. Furthermore, the lossless negative imaginary property of improper descriptor systems is derived by the relationship between the lossless positive realness and the lossless negative imaginariness. Several examples are given to illustrate the obtained results. In addition, this paper presents a generalized Kalman–Yakubovich–Popov lemma for the negative imaginary property of descriptor systems, which is achieved independently of the relationship between positive realness and negative imaginariness.
期刊介绍:
The Journal of The Franklin Institute has an established reputation for publishing high-quality papers in the field of engineering and applied mathematics. Its current focus is on control systems, complex networks and dynamic systems, signal processing and communications and their applications. All submitted papers are peer-reviewed. The Journal will publish original research papers and research review papers of substance. Papers and special focus issues are judged upon possible lasting value, which has been and continues to be the strength of the Journal of The Franklin Institute.