Open AccessSliding‐mode position control of medium‐stroke voice coil motor based on system identification observer
Author(s) -
Pan Jianfei,
Or Siu Wing,
Zou Yu,
Cheung Norbert Chow
Publication year - 2015
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.815
H-Index - 97
eISSN - 1751-8679
pISSN - 1751-8660
DOI - 10.1049/iet-epa.2014.0486
Subject(s) - control theory (sociology) , voice coil , controller (irrigation) , observer (physics) , sliding mode control , electromagnetic coil , state observer , position (finance) , stroke (engine) , engineering , control system , computer science , nonlinear system , physics , control (management) , mechanical engineering , artificial intelligence , agronomy , finance , quantum mechanics , electrical engineering , economics , biology
This study presents the performance improvement in the position control of a medium‐stroke voice coil motor (VCM) using a sliding‐mode controller (SMC) with a system identification observer (SIO). The proposed VCM is developed with a full stroke of 24 mm, and its non‐linear electro‐magneto‐mechanical characteristics are analysed by the three‐dimensional finite element method. A least‐squares‐based SIO is introduced into the VCM control system prior to the position regulation of the SMC in order to achieve a shorter rise time of 29 ms and a smaller steady‐state error of <±2 μm under a square‐wave excitation of 20 mm amplitude and 0.5 Hz frequency. An experimental verification between the SMC and a traditional proportion–integral–differential controller is carried out. The results demonstrate improved dynamic and static tracking responses in the SMC under load‐free, frequency‐varying operations.