This paper deals with the problem of estimating CSD (Crystal Size Distributions) during polymorphic crystallization processes. The proposed approach is based on the high gain observer using the discretization of the PBE’s (Population Balance Equations). First, in the growth phase, the monitoring of the nuclei production permits the estimation of the CSD using an adequate observer. In the dissol...

In disturbance-observer-based control, the closed loop system consists of a main feedback control loop and an inner disturbance observer loop. This paper presents a design method for a disturbance observer to satisfy closed loop performance specifications, provided that the main feedback controller is known. Taking advantage of certain fixedstructure disturbance observers, the disturbance obser...

In this paper, we investigate the use of adaptive extended Luenberger state estimators for general nonlinear and possibly time-varying systems. We identify the connection between the extended Luenberger observer and Grossberg’s additive model for dynamic neural networks. The association between dynamic neural networks and the Luenberger observer leads to an obvious modification on the proposed ...

In this paper, the performance of two adaptive observers applied to interconnected systems is studied. The nonlinearity of systems can be written in a fractional form. The first adaptive observer is an adaptive sliding mode observer for a Lipchitz nonlinear system and the second one is an adaptive sliding mode observer having a filtered error as a sliding surface. After comparing their performa...

In current industrial control applications, the proportionalþ integralþ derivative (PID) control is still used as the leading tool, but constructing controller requires precise mathematical model of plant, and tuning the parameters of controllers is not simple to implement. Motivated by the gap between theory and practice in control problems, linear active disturbance rejection control (LADRC) ...

The paper presents a cascade control scheme for Permanent Magnet Synchronous Motors (PMSMs) based on a novel reduced order state observer which provides accurate speed tracking performance. The asymptotic vanishing of both the observation error and the speed tracking error is proven. The observer design allows a residual signal to be defined, able to detect faults using Park’s vector currents. ...

This paper proposes a novel Space Vector Pulse width modulation (SVPWM) for sensor less control of induction motor using model reference adaptive system (MRAS). The steady state ripples in the torque are present in the conventionally used MRAS sensor less control of induction motor which utilizes normally used voltage source inverters. Also performance of the steady state speed is not as perfec...