Identification of Multivariable System Using Relay Tuning

Chemical and biochemical engineering quarterly

G. S. Dombe¹  M. Chidambaram¹ 

关键词: Relay tuning;    multivariable system;    IMC;   

DOI  :  

来源: Croatian Society of Chemical Engineers

【 摘 要 】

Abstract In this paper, the recently proposed method by Ramakrishnan and Chidambaram (2003)6 on identifying SOPTD transfer function model by asymmetric relay tuning method is extended to identify a multivariable system. The decentralized relay feedback method suggested by Wang et. al. (1997)11 is applied for the m × m system and m relay tests are required for identifying the entire transfer function matrix. Although, most of the processes can be adequately approximated by a FOPTD model, some of the processes are under-damped and higher order processes can be better incorporated by a SOPTD than a FOPTD model. Certain higher order stable models when approximated to a FOPTD model give a negative time constant, hence, identifying a second order model is necessary. The proposed method is applied to a 2 × 2 transfer function matrix. The multivariable IMC controllers are designed for the identified model and the closed loop performance of the actual and identified model is compared.

【 授权许可】

Unknown