Xianguo Gui

Adaptive Compensation Method of Position Estimation Harmonic Error for EMF-Based Observer in Sensorless IPMSM Drives

To improve the performance of sensorless interior permanent magnet synchronous motor (IPMSM) drives, a quadrature phase-locked loop (PLL) with an adaptive notch filter (ANF) is proposed for the model-based sliding-mode observer (SMO). The position estimation error with the sixth harmonic distortion caused by the inverter nonlinearity and the flux spatial harmonics is analyzed. The ANF based on adaptive noise canceling principle combined with the quadrature PLL is proposed to diminish the estimation harmonic error. This method can adaptively compensate the harmonics in the estimated electromotive force to eliminate the corresponding position estimation error. The estimated harmonic coefficients from the ANF can be continuously self-tuned using the least-mean-squares algorithm according to the estimated position information. The effectiveness of the proposed method is verified with the experimental results at a 2.2-kW IPMSM sensorless drive.

Position Estimation Error Reduction Using Recursive-Least-Square Adaptive Filter for Model-Based Sensorless Interior Permanent-Magnet Synchronous Motor Drives

To improve the performance of sensorless interior permanent-magnet synchronous motor (IPMSM) drives, an adaptive filter (AF) using recursive-least-square (RLS) algorithm is proposed for the electromotive force (EMF) model-based sliding-mode observer with a quadrature phase-locked loop (PLL) tracking estimator. The inverter nonlinearities and flux spatial harmonics, which cause the position estimation error with the sixth harmonic, are analyzed. An AF based on the adaptive noise-cancelling principle in cascade with a quadrature PLL is adopted to remove the harmonic estimation error. According to the harmonic characteristics of the estimation error from the quadrature PLL, the AF coefficients can be continuously updated by the RLS algorithm. The application of the RLS algorithm guarantees the fast convergence rate of the AF. Through the AF using the RLS algorithm, the harmonics of the estimated EMF can be effectively compensated. Therefore, the selected position estimation harmonic error can be eliminated. The effectiveness of the proposed method is verified with the experimental results at a 2.2-kW sensorless IPMSM drive.

On-line Inertia Identification Algorithm for PI Parameters Optimization in Speed Loop

This paper presents a novel on-line inertia identification method with a load torque observer to optimize the speed loop PID parameters of a servo system. The proposed inertia identification algorithm in this paper adopts the fixed-order recursive empirical frequency-domain optimal parameter estimation to improve the speed loop performance. A load torque observer is employed in order to obtain a more precise value of inertia. Then, the method of speed loop PI parameters optimization with the identified inertia and load torque is deduced in frequency domain. Compared with the recursive least square algorithm, the effectiveness of the proposed method is demonstrated by the simulation and experimental results.

Investigation of

Flux-weakening capability of permanent-magnet synchronous machines (PMSMs) is fundamentally determined by d- and q -axis inductances. Based on axial flux permanent-magnet machines (AFPMs), this paper extracts the intrinsic factors that influence the d- and q-axis inductances of PMSMs, meanwhile revealing the fact that the d- and q-axis inductances of fractional slot concentrated winding machines are not inevitably larger than that of distributed ones. The proportion of each of the d- and q-axis component inductances for multigap AFPMs is first studied. By analyzing armature inductance in conjunction with differential leakage inductance, this paper introduces a novel parameter to decouple the influence of slot-pole combinations and physical dimensions so that the “inductance ability” of different slot-pole combinations can be quantified. An improved method of calculating the slot leakage inductance of semiclosed slots is then put forward, which proves to be more accurate than the conventional method. The investigations and conclusion in this paper are not restricted to AFPMs but applicable to radial flux permanent-magnet machines as well. Validations of various slot-pole combinations are carried out with finite-element analysis and experiments.

d

Alternating-current motor drive systems consume the majority of global electricity, but most of them are still not efficient enough. This paper proposes a complete solution to the efficiency enhancement of general induction motor (IM) drive systems with the least cost and a high reliability. On the motor side, the squirrel-cage rotors of IMs are replaced with optimally designed interior permanent-magnet (PM) rotors without damping windings; meanwhile, other assemblies remained unchanged. Stators with both wye- and delta-connected windings are investigated, and super premium efficiency (IE4) is achieved on all the remanufactured motors in this paper. On the drive side, the maximum efficiency per ampere algorithm is realized based on the position-sensorless control to better exert the motor efficiency and reduce the system cost. For applications where an original IM is used under a grid drive, this paper safely switches the remanufactured interior PM synchronous motors from an inverter to the grid drive. A total of seven prototypes with different rated powers and velocities are remanufactured, and various experiments are provided as the verifications of the effectiveness and practicability of the proposed solution.

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This paper presents a novel algorithm to eliminate d-q axis static current error of PMSM predictive current control when the model in predictive controller has parameter mismatch with real system. The relationship between current error and parameter mismatch is analyzed numerically, and the static current error is eliminated by introducing current error integration in d-axis current control while dynamically adjusting the parameter of controller flux according to the q-axis current error. The algorithm is quite suitable for industrial application and is verified through simulation and experiment on a 3.3kW PMSM servo platform.

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In this paper, we describe a new optimum design procedure for speed controller considering anti-windup for PMSM drive system. Tuning of speed controller is complicated by nonlinearities. Usual practice obtains controller settings with conventional linear analysis methods and then tunes the settings using trial-and-error methods during commissioning. An alternative approach, using particle swarm optimization algorithm devised to test and compare different parameters of speed controller, we search for the anti-windup speed controller to achieving the optimal compromise of variable speed at full load. The search is performed on-line, on the physical hardware, by continuously downloading and testing new solutions on a DSP running the control algorithms in real time. The controller obtained through PSO significantly outperforms alterative schemes obtained with conventional design techniques.

-Axis Inductances Influenced by Slot-Pole Combinations Based on Axial Flux Permanent-Magnet Machines

This paper describe two PWM rectifier control using fixed-frequency SVPWM modulation. They are direct current control and direct power control based on the active and reactive power calculating. Comparative analyses are presented in the response speed, stability and harmonic content. It shows that direct current control system responses faster and is more stable. Total harmonic distortion value of direct current control is smaller. The reason that direct current control performs better is that there is feed forward decoupling in the system, thus it exhibits excellent features.

Efficiency Enhancement of General AC Drive System by Remanufacturing Induction Motor With Interior Permanent-Magnet Rotor

Efficient manipulation and locomotion skills of a humanoid robot largely depends on the performance of the servo controllers which are used at wrists, elbows, shoulders, ankles, knees, and hip joints. The requirements for humanoid robot joint servo controller include small size, low dissipation, high power density, high response speed and high control precision. Aiming at these technical requirements, based on permanent magnet synchronous motor (PMSM) vector control theory, minitype servo controller is developed applying for humanoid robot joint drives. The design methods and solutions of every functional module are given. The current loop, speed loop and position loop control strategy are analyzed. And the thermal analysis is included. Experimental results show that the servo controller had good performance and is suitable for humanoid robot joint drive system.

Improved predictive current control with static current error elimination for permanent magnet synchronous machine

A novel online particle swarm optimization is proposed to design anti-windup speed controller for PMSM drive system paper. It is complicated that conventional method with linear analysis and tuning the settings using trial-and-error methods during commissioning. An alternative approach, using particle swarm optimization algorithm devised to test and compare different parameters of speed controller, we search for the anti-windup speed controller to achieving the optimal compromise of variable speed at full load. The search is performed on-line, on the physical hardware, by continuously downloading and testing new solutions on a DSP running the control algorithms in real time. The controller obtained through PSO significantly outperforms alterative schemes obtained with conventional design techniques.