TY  - JOUR
SN  - 09591524
EP  - 1376
AV  - none
SP  - 1368
TI  - NLPCA as a diagnostic tool for control valve stiction
N1  - cited By 24
Y1  - 2009///
VL  - 19
UR  - https://www.scopus.com/inward/record.uri?eid=2-s2.0-70349164108&doi=10.1016%2fj.jprocont.2009.04.010&partnerID=40&md5=56bced8115bd0e1b2b0b24c186178d08
A1  - Zabiri, H.
A1  - Ramasamy, M.
JF  - Journal of Process Control
KW  - Control loop; Control valve; Control valves; Controlled variables; Controller outputs; Curvature indices; Diagnostic tools; In-process; Industrial case study; Non-linear correlations; Non-Linearity; Nongaussianity; Nonlinear behavior; Nonlinear principal component analysis; Operating data; Plant operations; Regression coefficient; Straight lines
KW  -  Nonlinear analysis; Process control; Safety valves; Stiction
KW  -  Principal component analysis
ID  - scholars707
N2  - A significant number of control loops in process plants perform poorly due to control valve stiction. Developing a method to detect valve stiction in the early phase is imperative to avoid major disruptions to the plant operations. Nonlinear principal component analysis (NLPCA), widely known for its capability in unravelling nonlinear correlations in process data, is extended in this paper to diagnose control valve stiction problems. The present work is based on distinguishing the difference between the shapes of the signals caused by stiction and other sources, and utilizes the operating data of controlled variable-controller output (pv-op). The structure of pv-op data used in this work is of sufficiently low dimension such that the NLPCA's output allows the usage of simple mathematical tests in quantifying the nonlinear behavior of the loop. It is shown that if the underlying structure of pv-op data is linear, the NLPCA output generally approximates to a straight line with a regression coefficient (R2) greater than 0.8, otherwise there is a possibility of presence of nonlinearity or non-Gaussianity. The presence of stiction is then detected via a new and simple NLPCA curvature index, INC. Results from simulated and real industrial case studies show that NLPCA is a very promising tool for detecting valve stiction. © 2009 Elsevier Ltd. All rights reserved.
IS  - 8
ER  -