关键词: 脉冲响应模型, 子空间辨识, 闭环辨识, 建模

Abstract: In view of the fact that it is difficult to gather the open-loop data of the control system in practice, a direct identification method of impulse response model based on subspace approach from closed loop data is presented. An orthogonal decomposition is first used to estimate the deterministic components of the joint input-output process. Then, closed loop identification problem can be converted to identify the plant with the deterministic components of the joint input-output process under open loop circumstance. Through exploiting the low triangular structure of Toeplitz matrix, the subspace matrix consisting of impulse response coefficients is estimated row by row. The impulse response model is derived by averaging elements of the estimated subspace matrix. Three simulation examples of SISO numerical simulation, MIMO numerical simulation and Wood-Berry distillation process are used to compare the proposed method、PBSID_OPT and CVA. Results of several simulations show the good performance of the proposed method. The results of this paper have actual significance of reference and guidance for the application of subspace identification method in the modeling of actual industrial process.

Key words: impulse response model, subspace identification, closed loop identification, modeling