On-line Estimation of Nonlinear and Time Varying Effects in Rotor System Using Qr Orderly Recursive Method
نویسندگان
چکیده
This paper investigates the on-line estimation of parameters and the determination of the significance of several nonlinear and time varying linear effects in rotor dynamic systems. These effects include nonlinear spring restoring forces, nonlinear structural damping, and the asymmetric stiffness of the shaft. Since these effects are all linear in the parameter, a linear regression scheme can be formulated to estimate the parameter. To solve this linear regression problem, an orderly recursive QR factorization method is used. Based on the estimated parameters and the residual error energies of a series of models, which are available from the QR orderly recursive method, a partial F-statistic test is used to determine the significance of each effect. The simulation results show that the parameters can be obtained after the resonant peak and the significance of these effects can be determined correctly if the sequence of these effects in the QR factorization matrix is carefully arranged. NOMENCLATURE Cuvw body-fixed coordinate system Cxyz intermediate non-spinning coordinate system between OXYZ and Cuvw OXYZ stationary inertial coordinate system h coefficient of the nonlinear structural damping k average of the stiffness of the shaft in two directions kij coefficient of the nonlinear spring restoring force. i,j=0...3 and i+j=3. It, Ip diametric and polar moment of inertia of the disk. y x θ θ , inclination angle in two directions of the disk y x θ θ , angular velocity of the disk y x θ θ , angular acceleration of the disk φ φ φ , , spinning angle, velocity, and acceleration of the rotor τ dynamic unbalance. It is an angle between the principle moment of inertia and the symmetrical axes. ∆ difference of the stiffness of the shaft in two directions
منابع مشابه
Identification of non-linear effects in rotor systems using recursive QR factorization method
There are several non-linear and time variant effects in a rotor-bearing dynamic system. The non-linear characteristics of the rolling element bearing, internal damping, unsymmetrical stiffness of the shaft, cracks on the shaft, and the radial clearance are the typical root causes of these effects [1]. As rotating speeds increase and rotor weights decrease, these non-linear and time variant eff...
متن کاملAn Adaptive Nonlinear Controller for Speed Sensorless PMSM Taking the Iron Loss Resistance into Account (RESEARCH NOTE)
In this paper, an adaptive nonlinear controller is designed for rotor Surface Permanent Magnet Synchronous Motor (SPMSM) drive on the basis of Input-Output Feedback Control (IOFC), and Recursive Least Square (RLS) method. The RLS estimator detects the motor electromechanical parameters, including the motor iron loss resistance online. Moreover, a Sliding-Mode (SM) observer is developed for onli...
متن کاملAdaptive Speed Control of Three-Phase Induction Servo-drives Based on Feedback Linearization Theory
In this paper, based on feedback linearization control method and using a special PI (propotational integrator) regulator (IP) in combination with a feed-forward controller, a three-phase induction servo-drive is speed controlled. First, an observer is employed to estimate the rotor d and q axis flux components. Then, two input-output state variables are introduced to control the dynamics of to...
متن کاملAdaptive Speed Control of Three-Phase Induction Servo-drives Based on Feedback Linearization Theory
In this paper, based on feedback linearization control method and using a special PI (propotational integrator) regulator (IP) in combination with a feed-forward controller, a three-phase induction servo-drive is speed controlled. First, an observer is employed to estimate the rotor d and q axis flux components. Then, two input-output state variables are introduced to control the dynamics of to...
متن کاملInvestigating Nonlinear Vibration Behavior of Rotors with Asymmetry Shaft Considering Misalignment
In this paper, the nonlinear vibration behavior of a rotor with asymmetric shaft considering misalignment is studied. The system consists of a rectangular shaft and a disk which is connected to a motor through a flexible coupling. In order to consider higher order deformations, nonlinear Bernoulli beam is used for modeling the shaft. Gibbons’ equations are utilized to apply misaligned coupling ...
متن کامل