An Adaptive Nonlinear Extended State Observer for the Sensorless Speed Control of a PMSM

This paper presents a sensorless speed control strategy for a permanent-magnet synchronous motor (PMSM) based on an adaptive nonlinear extended state observer (ANLESO). In this paper, an extended state observer (ESO), which takes back-EMF (back electromotive force) as an extended state, is used to estimate the rotor position and the rotor speed because of its simpler structure and higher accuracy. Both linear ESO (LESO) and nonlinear ESO (NLESO) are considered to estimate the back-EMF of PMSM, and NLESO is finally implemented due to its obvious advantage in convergence. The convergence characteristics of the estimation error of the observer are analyzed by the Lyapunov theory. In order to take both stability and steady-state error into consideration, an adaptive NLESO is proposed, which adaptively adjusts the parameters of NLESO to a compromised value. The performance of the proposed method was demonstrated by simulations and experiments.

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Sampled-data extended state observer-based backstepping control of two-link flexible manipulator

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331219832954 ◽

2019 ◽

Vol 41 (13) ◽

pp. 3581-3599 ◽

Cited By ~ 3

Author(s):

Umesh Kumar Sahu ◽

Bidyadhar Subudhi ◽

Dipti Patra

Keyword(s):

Control Strategies ◽

Estimation Error ◽

Experimental Studies ◽

State Observer ◽

Lyapunov Theory ◽

Extended State Observer ◽

Flexible Manipulator ◽

Sampled Data ◽

Extended State ◽

Model Uncertainties

Currently, space robots such as planetary robots and flexible-link manipulators (FLMs) are finding specific applications to reduce the cost of launching. However, the structural flexible nature of their arms and joints leads to errors in tip positioning owing to tip deflection. The internal model uncertainties and disturbance are the key challenges in the development of control strategies for tip-tracking of FLMs. To deal with these challenges, we design a tip-tracking controller for a two-link flexible manipulator (TLFM) by developing a sampled-data extended state observer (SD-ESO). It is designed to reconstruct uncertain parameters for accurate tip-tracking control of a TLFM. Finally, a backstepping (BS) controller is designed to attenuate the estimation error and other bounded disturbances. Convergence and stability of the proposed control system are investigated by using Lyapunov theory. The benefits (control performance and robustness) of the proposed SD-ESO-based BS controller are compared with other similar approaches by pursuing both simulation and experimental studies. It is observed from the results obtained that SD-ESO-based BS Controller effectively compensates the deviation in tip-tracking performance of TLFM due to non-minimum phase behavior and model uncertainties with an improved transient response.

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Speed Control of Permanent Magnet DC Motor with Friction and Measurement Noise Using Novel Nonlinear Extended State Observer-Based Anti-Disturbance Control

Energies ◽

10.3390/en12091651 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1651 ◽

Cited By ~ 14

Author(s):

Amjad J. Humaidi ◽

Ibraheem Kasim Ibraheem

Keyword(s):

Permanent Magnet ◽

Finite Time ◽

Nonlinear Function ◽

State Observer ◽

Lyapunov Theory ◽

Extended State Observer ◽

Extended State ◽

Disturbance Rejection Control ◽

Single Term ◽

Nonlinear Extended State Observer

In this paper, a novel finite-time nonlinear extended state observer (NLESO) is proposed and employed in active disturbance rejection control (ADRC) to stabilize a nonlinear system against system’s uncertainties and discontinuous disturbances using output feedback based control. The first task was to aggregate the uncertainties, disturbances, and any other undesired nonlinearities in the system into a single term called the “generalized disturbance”. Consequently, the NLESO estimates the generalized disturbance and cancel it from the input channel in an online fashion. A peaking phenomenon that existed in linear ESO (LESO) has been reduced significantly by adopting a saturation-like nonlinear function in the proposed nonlinear ESO (NLESO). Stability analysis of the NLEO is studied using finite-time Lyapunov theory, and the comparisons are presented over simulations on permanent magnet DC (PMDC) motor to confirm the effectiveness of the proposed observer concerning LESO.

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Improved Nonlinear Extended State Observer-Based Sliding-Mode Rotary Control for the Rotation System of a Hydraulic Roofbolter

Entropy ◽

10.3390/e24010041 ◽

2021 ◽

Vol 24 (1) ◽

pp. 41

Author(s):

Zhen Zhang ◽

Yinan Guo ◽

Xianfang Song

Keyword(s):

Sliding Mode Control ◽

Sliding Mode ◽

Estimation Error ◽

Dead Zone ◽

State Observer ◽

Extended State Observer ◽

Extended State ◽

Mode Control ◽

Rotation System ◽

Nonlinear Extended State Observer

This paper develops a sliding-mode control with an improved nonlinear extended state observer (SMC-INESO) for the rotation system of a hydraulic roofbolter with dead-zones, uncertain gain, and disturbances, with the purpose of improving tracking performance. Firstly, the rotation system is modeled to compensate for dead-zone nonlinearity. Then, we present an improved nonlinear extended state observer to estimate disturbances of the rotation system in real time. Moreover, a proportional-integral-differential sliding-mode surface is introduced and an improved sliding-mode reaching law is designed. Based on this, a sliding-mode control law is developed. In order to eliminate the influence of estimation error and uncertain gain, we design two adaptation laws based on the sliding-mode surface and the estimated states. Finally, the effectiveness of the proposed SMC-INESO is verified through comparative simulation studies.

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Speed control for permanent magnet synchronous motor based on an improved extended state observer

Advances in Mechanical Engineering ◽

10.1177/1687814017747663 ◽

2018 ◽

Vol 10 (1) ◽

pp. 168781401774766 ◽

Cited By ~ 11

Author(s):

Bingyou Liu

Keyword(s):

Control System ◽

Permanent Magnet ◽

Permanent Magnet Synchronous Motor ◽

Speed Control ◽

Synchronous Motor ◽

State Observer ◽

Extended State Observer ◽

Motor Speed ◽

Extended State ◽

Speed Control System

An improved extended state observer is designed to eliminate the influences of speed control for a permanent magnet synchronous motor. The improved extended state observer is designed based on a new nonlinear function. This function exhibits better continuity and derivability than previously available functions and can effectively reduce the high-frequency flutter phenomenon. The nonlinear dynamics, model uncertainty, and external disturbances of the permanent magnet synchronous motor speed control system are extended to a new state. The improved extended state observer is utilized to observe this state. The overtime variation of the permanent magnet synchronous motor speed control system can be predicted and compensated in real time by the improved extended state observer. Therefore, the improved extended state observer, which is designed based on the new nonlinear function, can eliminate the disturbances on the permanent magnet synchronous motor speed control system. Finally, simulation experiments are performed and results show that the permanent magnet synchronous motor speed control system with improved extended state observer exhibits better performances.

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