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Journal of Central South University 2015年第5期22卷 1716-1724页

作者：邓江明陈特放陈春阳 School of Information Science and Engineering Central South University School of Traffic Transportation and Engineering Central South University

An adaptive current compensation control for a single-sided linear induction motor(SLIM) with nonlinear disturbance observer was developed. First, to maintain t-axis secondary component flux constant with consideration of the specially dynamic eddy-effect(DEE) of the SLIM, a instantaneously tracing compensation of m-axis current component was analyzed. Second,adaptive current compensation based on Taylor-discretization algorithm was proposed. Third, an effective kind of nonlinear disturbance observer(NDOB) was employed to estimate and compensate the undesired load vibrations, then the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed method for an SLIM control system was performed, and it showed that the proposed adaptive compensation scheme with NDOB could significantly promote speed dynamical response and minimize speed ripple under the conditions of external load coupled vibrations and unavoidable feedback control variables measured errors, i.e., current and speed.

关键词： single-sided linear induction motors(SLIMs) current compensation adaptive control dynamical response nonlinear disturbance observer(NDOB)

current Polarity Detection and current compensation Strategy for PAC Based Three-Phase ZVS PWM Converter

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Journal of Shanghai University(English Edition) 2005年第6期9卷 539-543页

作者：屈克庆陈国呈孙承波 School of Electromechanical Engineering and Automation Shanghai University Shanghai 200072 P.R. China Shanghai Key Laboratory of Power Station Automation Technology Shanghai 200072 P. R. China

A novel software implementation for current polarity detection and current compensation is presented. For a three-phase zero-voltage soft-switching （ZVS） PWM converter based on phase and amplitude control （PAC）, when saw-tooth carriers with alternate positive and negative slopes are adopted, the positive or negative slopes are chosen according to the phase current polarity. Since polarity reversal causes current distortion, current at the instant of reversal should be compensated for. Based on the characteristic of unity power factor converter in rectification and regeneration modes, a software implementation for current polarity detection is proposed. Distortion of current zero-crossing caused by using saw-tooth carriers with alternate positive and negative slopes is analyzed, and the relevant compensation method is proposed. Experimental study with a 1.5 kW device shows that phase current has a small harmonic content and power factor is high both in rectification and regeneration modes.

关键词： current polarity detection current compensation converter ZVS PAC.

A New Method to IMprove the LVRT of DFIG Based on the current compensation

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A New Method to IMprove the LVRT of DFIG Based on the Curren...

Design of improved CMOS phase-frequency detector and charge-pump for phase-locked loop

第三十届中国控制会议

作者： CHEN Jinmei~1,XUE Ancheng~1,TIAN Chunguang~2,BI Tianshu~1,GAO Changzheng~2 1.State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University,Beijing 102206,P.R.China 2.Electric Power Research Institute,Jilin Electric Power Company Limited,Changchun 130021,P.R.China

＜正＞Doubly fed induction generator（DFIG） has been widely used as its converter capacity is small.However,the low voltage ride through（LVRT） of DFIG is still a problem.This paper proposed a new LVRT controller based on the philosophy of current compensation.First,base on the Laplace Transform,this paper analyzes the rotor and stator current transients under the grid fault,focused on the influence of the stator DC flux.And then,it proposes a combination control strategy consisting of current compensation control and DC crowbar control improve the LVRT of DFIG.The simulation with the RTDS verified the effectiveness of the proposed control strategy.

关键词： Doubly Fed Induction Generator（DFIG） Low Voltage Ride Through（LVRT） current compensation Crowbar

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Journal of Semiconductors 2014年第10期35卷 119-125页

作者：刘法恩王志功李智群李芹陈胜 Engineering Research Center of RF-ICs and RF-Systems Ministry of Education

Two essential blocks for the PLLs based on CP, a phase-frequency detector （PFD） and an improved current steering charge-pump （CP）, are developed. The mechanisms for widening the phase error detection range and eliminating the dead zone are analyzed and applied in our design to optimize the proposed PFD. To obtain excellent current matching and minimum current variation over a wide output voltage range, an improved structure for the proposed CP is developed by fully utilizing many additional sub-circuits. Implemented in a standard 90-nm CMOS process, the proposed PFD achieves a phase error detection range from -354° to 354° and the improved CP demonstrates a current mismatch of less than 1.1% and a pump-current variation of 4% across the output voltage, swinging from 0.2 to 1.1 V, and the power consumption is 1.3 mW under a 1.2-V supply.

关键词： CMOS phase-frequency detector charge-pump current compensation accelerating acquisition PLL

Underwater docking of an under-actuated autonomous underwater vehicle:system design and control implementation

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Frontiers of Information Technology & Electronic Engineering 2018年第8期19卷 1024-1041页

作者： Bo LI Yuan-xin XU Shuang-shuang FAN Wen XU College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China

Underwater docking greatly facilitates and extends operation of an autonomous underwater vehicle(AUV) without the support of a surface vessel. Robust and accurate control is critically important for docking an AUV into a small underwater funneltype dock station. In this paper, a docking system with an under-actuated AUV is presented, with special attention paid to control algorithm design and implementation. For an under-actuated AUV, the cross-track error can be controlled only via vehicle heading modulation, so both the cross-track error and heading error have to be constrained to achieve successful docking operations, while the control problem can be even more complicated in practical scenarios with the presence of unknown ocean currents. To cope with the above issues, a control scheme of a three-hierarchy structure of control loops is developed, which has been embedded with online current estimator/compensator and effective control parameter tuning. The current estimator can evaluate both horizontal and vertical current velocity components, based only on the measurement of AUV's velocity relative to the ground; in contrast, most existing methods use the measurements of both AUV's velocities respectively relative to the ground and the water column. In addition to numerical simulation, the proposed docking scheme is fully implemented in a prototype AUV using MOOS-IvP architecture. Simulation results show that the current estimator/compensator works well even in the presence of lateral current disturbance. Finally, a series of sea trials are conducted to validate the current estimator/compensator and the whole docking system. The sea trial results show that our control methods can drive the AUV into the dock station effectively and robustly.

关键词： Autonomous underwater vehicle (AUV) Docking systems current estimator current compensation Docking control

Thrust control of superconducting DC linear motor for electromagnetic launch

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Thrust control of superconducting DC linear motor for electr...

Design and Implementation of Full Speed Range Control of Permanent Magnet Synchronous Motor for Electric Vehicle

第36届中国控制会议

作者： Guanchun Li Jie Li Engineering Research Center of Maglev Technology National University of Defense Technology

This paper presents a thrust control based on current compensation.The controller is designed based on the relationship between current and back-EMF,and the control scheme is assessed through simulation study.Simulati... 详细信息

ISBN: (纸本)9781538629185

关键词： Thrust control current compensation SDCLM

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Design and Implementation of Full Speed Range Control of Per...