학술논문

Instantaneous speed and disturbance torque observer using nonlinearity cancellation of shaft encoder
Document Type
Conference
Author
Source
2002 IEEE 33rd Annual IEEE Power Electronics Specialists Conference. Proceedings (Cat. No.02CH37289) Power electronics specialists conference Power Electronics Specialists Conference, 2002. pesc 02. 2002 IEEE 33rd Annual. 2:540-545 vol.2 2002
Subject
Power, Energy and Industry Applications
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Robotics and Control Systems
Signal Processing and Analysis
Computing and Processing
Torque
Shafts
Observers
Analytical models
Quantization
Filters
State estimation
Noise measurement
Sampling methods
Noise reduction
Language
Abstract
In this paper, the theoretical analysis, simulations and practical results of a new speed and disturbance torque observer are proposed. The analysis of the nonlinearity introduced by the encoder quantization allows improving the behaviour of the filter in all the speed range. A Kalman filter type observer has been developed. The main novelty is that the state estimate observational update takes place at the quantized position signal discontinuities. Unlike the usually, applied Kalman filter, the measurement noise covariance is variable. In this observer, it is a function of the shaft speed because the selection of the sampling instant results in a reduction of the output noise covariance. The observer adapts its gain depending on the state variables. The optimal gain calculation results in an observer bandwidth increase. Another advantage of this observer is that the self-sustained. oscillations are suppressed, obtaining asymptotic stability.