A robust uncertainty controller with system delay compensation for an ILPMSM system with unknown system parameters

A robust uncertainty controller with a system delay compensation for an ironless linear permanent-magnet synchronous motor (ILPMSM) system with unknown system parameters has been investigated. The proposed controller consists of an inverse of the first-order reference model with an input deduction and integral term. The system delay compensation adopts an inverse system delay model to compensate the system transport delay effect. The proposed control scheme can reduce modeling uncertainty due to the difference between the reference model and the unknown real system model and disturbance due to d-q-axis coupling effect. The advantages of the proposed control algorithm are as follows: First, the system response which can be achieved is similar to that of the designed nominal reference model. In other words, the dc gain of the controlled system is denoted as one, so the proposed algorithm does not need to be combined with other control algorithms. Second, it does not require the system parameters to be known precisely. Our experimental results confirm the feasibility of the proposed scheme to compensate for the effects of uncertainty disturbances and system transport delay in the practical application of an ILPMSM system with unknown parameters.