Sensorless Control of IPMSM Drives Based on Extended State Observer With Enhanced Position Estimation Accuracy

A nonlinear Third-Order Extended State Observer (TESO) is proposed for the estimation of the rotor position and speed for sensorless Interior Permanent Magnet (IPM) synchronous motor drives. An optimized parameter tuning method is deployed to reconcile the needs of expanding the disturbance observation bandwidth and suppressing the measurement noise effectively. Both the steady state and transient performance of the TESO are verified through the experimental tests. In comparison with the performance of a conventional Linear Extended State Observer (LESO), the proposed observer is proved to have better noise suppression ability and disturbance observation performance in wide operating range.

This paper proposes a new move toward to assess the performance of sensorless control of interior permanent magnet synchronous motor (IPMSM) drive along with electromagnetic noise effect by using EKF. Normally in rotary condition, rotor position and speed estimation of IPMSM drive are drawn through an Extended Kalman Filter (EKF) algorithm by measuring its voltages and currents of the stator. The main drawback in developing EKF is it may not proficient to consider the effect of electromagnetic noise which is mainly produced during the time of different speed ranges. Owing to this reason this may cause to vary the motor flux linkages which are significant to find the rotor position and speed by EKF method will give approximate results. To carry on this process, we present the simulation results for sensorless speed control of IPMSM drive by using EKF algorithm with the incorporation of a noise signal which is corresponding to the frequency of electromagnetic noise signal using MATLAB/Simulink software. The armature current, rotor position, and speed estimation are analyzed under this noise signal effect and the effectiveness of the EKF for sensorless control of IPMSM drive is observed.

Sensorless control of high-speed permanent magnet synchronous motors (HSPMSMs) using the conventional extended state observer (ESO) exhibits limitations in accurately estimating the back electromotive force (BEMF). Such phase delays adversely affect the performance and dynamic response of HSPMSMs. To address this issue, a cascade high-order extended state observer (CHESO) is proposed to enhance position estimation and speed control of HSPMSMs. The effectiveness of the CHESO in extending the observation bandwidth and improving control accuracy is demonstrated. In the proposed two-level CHESO architecture, the BEMF is accurately estimated at the first level, while position, load torque, and uncertain disturbances are concurrently estimated at the second level. Subsequently, the estimated disturbances and load torque are employed in an adaptive feedforward control strategy to enhance the dynamic performance and anti-disturbance capability of the HSPMSM control system. Compared to the conventional ESO, the proposed CHESO minimizes position estimation errors and improves the estimation accuracy of high-speed regions, as verified by experimental results.

This paper presents a sliding mode synchronization controller (SMSC) based on extended state observer (ESO) for the dual-drive system in gantry-type machine tools (GTMT). This controller achieves not only excellent tracking accuracy but also high synchronization performance. Firstly, a sliding mode synchronization controller is designed for the dual-drive system based on a simplified mode. Then, in order to handle the difficulties associated with the parameter uncertainties, external disturbances and coupling effects of the dual-drive system, a linear extended state observer (LESO) is designed. In this active disturbance rejection control (ADRC) technology, the total disturbances are treated as an extended state of the system and compensated with the disturbance observed value. Moreover, Rigorous theoretical analysis is performed to show that the proposed control method is able to achieve asymptotical tracking and synchronization performance for the dual-drive system in GTMT. Finally, Simulation studies are carried out and the results show that the proposed control strategy performs an improved tracking and synchronization motion control in comparison to the independent axis P-PI control approach.

Considering the strong nonlinearity, fast time-varying and strong coupling dynamic characteristics of the high-speed vehicles (HSV), combining with the fact that the extended state observer (ESO) can effectively observe the total disturbance of the system and the predictive sliding mode controller (PSMC) has strong robustness and the ability to reduce chattering, a predictive sliding mode control method with extended state observer is proposed in this paper. Firstly, the HSV model is simplified for the attack angle control; Secondly, the tracking sliding mode surface is predicted and the sliding mode control law is derived by using the optimized performance index, which will avoid the switching function and reduce chattering effectively; Thirdly, a linear extended state observer (LESO) is designed to observe the parameters perturbation and the total disturbances of the system, the estimated value is compensated into the PSMC. Fourthly, the numerical simulation shows that the PSMC with LESO can track the step instruction of angle of attack stably even if there are parameters deviations and external composite disturbances. In addition, the control amount does not exceed the rudder deflection angle of the actuator, and the chatter phenomenon is effectively alleviated.

The dual observation of periodic and aperiodic interferences cannot be balanced by traditional linear extended state observer (T-LESO). Therefore, the speed fluctuations caused by uncertain periodic and aperiodic interferences in the interior permanent magnet synchronous motor control system cannot be suppressed by the traditional linear active disturbance rejection controller. To resolve the aforementioned problem, an improved linear active disturbance rejection controller (I-LADRC) in which multifrequency quasi-resonant filtering decoupling linear extended state observer and generalized linear extended state observer (G-LESO) are cascaded is proposed. In this controller, the interference feedforward control method of T-LESO is first changed, the observer bandwidth <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ω_o</i> and controller bandwidth <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ω_c</i> in the transfer function based on the interference term are decoupled from each other, reducing the difficulty of parameter tuning. On this basis, a multifrequency quasi-resonant filter is embedded in the decoupled linear extended state observer (LESO), so that periodic interferences can be accurately observed. For G-LESO, a fourth-order LESO is adopted to enable more accurate observation of aperiodic high-order interferences. The outer loop controller based on I-LADRC is designed, and the correctness and effectiveness of this method are verified through experiments.

This paper presents the fuzzy logic-based speed control of an interior permanent magnet synchronous motor (IPMSM) drive. The fundamentals of fuzzy logic algorithms related to motor control applications are illustrated. A new fuzzy speed controller for the IPMSM drive is designed. The efficacy of the proposed fuzzy logic controller (FLC) based IPMSM drive is verified by simulation as well as experimental results at different dynamic operating conditions. The fuzzy logic controller is found to be robust for application in the IPMSM drive. The complete vector control scheme incorporating the FLC is implemented in real-time using a digital signal processor (DSP) controller board DS 1102 in a laboratory 1 hp interior permanent magnet synchronous motor.

Disturbances and uncertainties are the main concerns in control systems. To obtain this information in real time, the extended state observer is proposed as the core of the active disturbance rejection control. However, the estimation errors of extended state observer cannot converge to zero in the presents of unknown but bounded disturbances, which will bring unexpected tracking errors to the closed-loop system. By taking advantage of the linear extended state observer and the super-twisting algorithm, the super-twisting extended state observer is proposed to deal with the non-diminishing second-order derivable disturbances in this paper. The asymptotic convergence of the super-twisting extended state observer and the controller are proved by the Lyapunov method. Moreover, the effectiveness and robustness of the super-twisting extended state observer are verified by simulation analysis. Simulation results show that the proposed super-twisting extended state observer maintains the minimized estimation error with less settling time compared the with linear extended state observer. The tracking performance of the controller with the proposed observer is greatly improved.

A new sensorless control scheme for Interior Permanent Magnet Synchronous Motor (IPMSM) drives is presented in this paper. In this method, high-frequency low-amplitude current is injected to the stationary α-axis and the corresponding high frequency voltage and the injected current are used to solve for rotor position based on the mathematical model of the motor in the stationary α-β frame. This method does not neglect any term in the mathematical model of the motor and therefore can estimate the rotor position accurately from standstill to the rated speed. The method solves for the rotor position in the stationary α-β frame and therefore is easy to implement. The method has been verified with simulation results, which show the position estimation error of the method is from 1°(electrical) at standstill to 4° at the rated speed.

This paper proposes a novel class of adaptive extended state observers (AESOs) that significantly expand the applications of extended state observers (ESOs) to nonlinear disturbed systems. An AESO is designed as a linear time-varying form that, as a result, combines both the advantages of theoretical completeness in a conventional linear ESO (LESO) and good practical performance in a conventional nonlinear ESO (NESO). To tune the time-varying observer gains, AESO error dynamics is first transformed into a canonical (phase-variable) form. Then, time-varying PD-eigenvalues are assigned for the canonical system based on differential algebraic spectral theory. Theorems for stability and estimate error bounds of the AESO are given in the presence of unknown disturbances. These theorems also offer some important guidelines for assigning the PD-eigenvalues. To demonstrate the effectiveness of this new observer, two representative applications, including a numerical single-input–single-output example and a practical multiple-input–multiple-output hypersonic vehicle application, are exemplified, and comparison simulations are conducted among AESO, LESO, and NESO. Future work is pointed out in the end.

This paper presents a sliding mode controller for an interior permanent magnet (IPM) synchronous motor, in which direct torque control (DTC) concept, variable structure control and space vector modulation (SVM) are integrated to achieve high performance. In comparison with conventional DTC, the inverter switching frequency is constant and controllable by using SVM, the torque and flux ripple are significantly reduced. The fast response and robustness merits of DTC are preserved. Position and angular speed of the rotor are obtained through an extended Kalman filter (EKF).

Because traditional direct torque control (DTC) has unfixed switching frequency and ripple of torque and flux, deadbeat direct torque and flux control (DB-DTFC) of interior permanent magnet synchronous motor (IPMSM) is studied. At first, DB-DTFC based on IPMSM mathematical model is deduced. The calculated proper voltage vector can make reference torque and stator flux during one sampling period. But, parameters of IPMSM such as inductance of stator windings vary with its operation and affect on torque and flux performance. Secondly, parameter identification based on recursive least squares with forgetting factor is analyzed, which can identify IPMSM parameters online and eliminate their affects on performance of torque and stator flux. Finally, simulations are carried out and validate the proposed DB-DTFC which has both excellent dynamic and steady performance.

This study is focused on very low speed performance comparison between two sensorless control systems based on the novel `active flux` concept, that is, the current/voltage vector control versus direct torque and flux control (DTFC) for interior permanent magnet synchronous motor (IPMSM) drives with space vector modulation (SVM), without signal injection. The active flux, defined as the flux that multiplies iq current in the dq -model torque expression of all ac machines, is easily obtained from the stator-flux vector and has the rotor position orientation. Therefore notable simplification in the rotor position and speed estimation is obtained. For IPMSM, a stator-flux observer is employed based on combined current and voltage models, with speed-dependent smooth transition between them using a PI compensator of flux error. Comparative experimental results using both sensorless control systems are presented to verify the principles and to demonstrate the effectiveness of the active flux observer at very low speeds from 20 to 2 rpm (1 0.1 Hz).

A control strategy for constructing current active disturbance rejection controller based on $\alpha$ and $\beta$ axial current as the main variable of the extended state observer is presented, to realize the high performance control of the interior permanent magnet synchronous motor without position sensor. In the two-phase stationary coordinate system, the current active disturbance rejection controller takes currents as input, voltages which drive motor by an inverter as output directly, so the accumulated error caused by the application of the rotor position angle in multiple coordinate transformations is eliminated, thus improving the control accuracy of the system apparently. Also, through the expansion state observer in the current active disturbance rejection controller, the differential of active flux containing the rotor position information is observed and compensated as the unknown perturbation, and taken as input to the phase-locked loop; therefor, the accurate speed and the rotor position angle are obtained, and the high precision control of the motor is realized. The simulation results show that the method has such advantages as high control precision, strong anti-interference ability.

This paper proposes an improved PLL-type estimator for self-sensing control based on back-electromotive force (back-EMF)estimation in an interior permanent magnet synchronous motor (IPMSM). Although the position and speed of rotor are accurately estimated by PLL-type estimator in steady state, the estimated information in transient state may be unstable. To analyze the transient performance of rotor position estimators, the structure design and proposed methods of estimator are introduced. And, the effect of proposed method has been figured out that the estimated speed error and torque ripple are decreased in transient state. The feasibility of the introduced estimator effect are verified through simulation results.