Application of H2 -based Sliding Mode Control for an Active Magnetic Bearing System

In this paper, application of Sliding Mode Control (SMC) technique for an Active Magnetic Bearing (AMB) system with varying rotor speed is considered. The gyroscopic effect and mass imbalance inherited in the system is proportional to rotor speed in which this nonlinearity effect causes high system instability as the rotor speed increases. Transformation of the AMB dynamic model into regular system shows that these gyroscopic effect and imbalance lie in the mismatched part of the system. A H2-based sliding surface is designed which bound the mismatched parts. The solution of the surface parameter is obtained using Linear Matrix Inequality (LMI). The performance of the controller applied to the AMB model is demonstrated through simulation works under various system conditions.

• Abdul Rashid Husain
• Mohamad Noh Ahmad
• Abdul Halim Mohd. Yatim

• Active magnetic bearing
• sliding mode control
• linear matrix inequality
• mismatched uncertainty and imbalance.

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