Adaptive Internal Model Control Scheme Research Articles

Fuzzy Adaptive Internal Model Control Schemes for PMSM Speed-Regulation System

In this paper, the speed regulation problem for permanent magnet synchronous motor (PMSM) system under vector control framework is studied. First, a speed regulation scheme based on standard internal model control (IMC) method is designed. For the speed loop, a standard internal model controller is first designed based on a first-order model of PMSM by analyzing the relationship between reference quadrature axis current and speed. For the two current loops, PI algorithms are employed respectively. Second, considering the disadvantages that the standard IMC method is sensitive to control input saturation and may lead to poor speed tracking and load disturbance rejection performances, a modified IMC scheme is developed based on a two-port IMC method, where a feedback control term is added to form a composite control structure. Third, considering the case of large variations of load inertia, two adaptive IMC schemes with two different adaptive laws are proposed. A method based on disturbance observer is adopted to identify the inertia of PMSM and its load. Then a linear adaptive law is developed by analyzing the relationship between the internal model and identified inertia. Considering the control input saturation in practical applications, a fuzzy adaptive law based IMC scheme is developed based on apriori experimental tests and experiences, where a fuzzy inferencer based supervisor is designed to automatically tune the parameter of speed controller according to the identified inertia. The effectiveness of the proposed methods have been verified by Matlab simulation and TMS320F2808 DSP experimental results.

Adaptive Internal Model Control with fractional order parameter

AbstractIn this paper we have introduced as a model in the adaptive Internal Model Control (IMC) structure a fractional order system to obtain a fractional adaptive IMC scheme. We have shown that this adaptive control scheme always provides theoretical guarantees of stability when a stable fractional order transfer function is used as an IMC parameter and that the use of this fractional IMC parameter can improve the performances of the control system along with its robustness against noises. A comparative simulation example is given to illustrate the efficiency of the proposed fractional order adaptive control scheme. Copyright © 2010 John Wiley & Sons, Ltd.

Internal model control structure using adaptive inverse control strategy

In this paper, we propose a new adaptive internal model control scheme based on adaptive finite impulse response filters. This scheme provides the same design procedure for both minimum and nonminimum phase plants. The plants under consideration may contain time delay. The tracking objective is accomplished for both invertible and noninvert-ible stable plants. The internal model of the plant and its inverse are estimated by recursive least-squares and least-mean-squares algorithms, respectively. The closed loop is designed such that the system from the reference input to the plant output can be approximately represented by a pure delay. The effect of the process zeros on the output is compensated by using adaptive finite impulse response filters. This avoids the cancellation of noncancellable zeros of the plant and forces the plant output to track the reference input with a delay. The stability of the closed loop for both minimum and nonminimum phase systems is guaranteed. Computer simulation and laboratory scale experimental results are included in the paper to demonstrate the effectiveness of the proposed method.

Adaptive internal model control: H/sub ∞/ optimization for stable plants

This paper considers the design of a robust adaptive H/sub /spl infin// optimal controller based on the IMC structure. Specific attention is focused on the practically important class of stable plants with one open right half-plane zero. The certainty equivalence principle of adaptive control is used to combine a robust adaptive law with a robust H/sub /spl infin// internal model controller to obtain an adaptive H/sub /spl infin// internal model control scheme with provable guarantees of stability and robustness. The approach used earlier for designing and analyzing adaptive H/sub 2/ optimal control schemes is seen to carry over in a natural fashion to the adaptive H/sub /spl infin// optimal control case. This attests to the generality of that approach, which not only provides a theoretical basis for analytically justifying some of the reported industrial successes of existing adaptive internal model control schemes, but also opens up the possibility of synthesizing new ones by simply combining a robust adaptive law with a robust internal model controller structure.

Adaptive internal model control: H2 optimization for stable plants

This paper considers the design and analysis of a pointwise optimal adaptive internal model control scheme. Using a series-parallel identification model, the “internal model” for an open loop stable plant is adapted on-line and the time-varying internal model control “parameter” is chosen in a certainty equivalence fashion to pointwise minimize an H 2 performance index. Stability of the resulting scheme and its robustness to plant modelling errors are established. The results here provide a suitable theoretical basis for analytically justifying some of the reported industrial successes of adaptive internal model control schemes.

Adaptive Internal Model Control: H2 Optimization for Stable Plants

This paper considers the design and analysis of a pointwise optimal adaptive internal model control scheme. Using a series-parallel identification model, the "internal model" for an open loop stable plant is adapted on-line and the time-varying internal model control "parameter" is chosen in a certainty equivalence fashion to pointwise minimize an H2 performance index. Stability of the resulting scheme and its robustness to plant modelling errors are established without having to check any Strictly Positive Real conditions or requiring any Persistent Excitation. The results here provide a firm theoretical basis for analytically justifying some of the reported industrial successes of Adaptive Internal Model Control schemes.

Adaptive internal model control: Design and stability analysis

This paper shows how adaptation can be combined with an internal model control structure to obtain an adaptive internal model control scheme possessing theoretically provable guarantees of stability. The internal model controller structure is first reviewed in the context of the YJBK parametrization of all stabilizing controllers, and its appropriateness for the control of open-loop stable plants is discussed. Using a series-parallel identification model, it is then shown how, for a stable plant, one can adapt the internal model on-line and guarantee stability and asymptotic performance in the ideal case i.e. in the absence of modelling errors. This is achieved without having to check any strictly positive real conditions or requiring any persistent excitation. By robustifying the adaptive law using standard approaches from the robust adaptive control literature, the robustness of the scheme to the presence of modelling errors, such as unmodelled dynamics, is also established. The theoretical developments here complement the reported industrial successes of internal model control schemes.