Hongxing Wu

Adaptive back-stepping control for the sectioned permanent magnetic linear synchronous motor in vehicle transportation system

Compared to other kinds of motor used in the vehicle transportation systems, the permanent magnet linear synchronous motor (PMSLM) is favorable for the advantages such as high efficiency, high power density, excellent controllability and without middle mechanical transmission. Dividing the long primary into sections, the sectioned PMLSM does well in energy saving, secularity, reliability and maintenance. In this paper, the sectioned PMLSM used in vehicle transportation system (VTS) is designed, whose winding in the primary is divided into two sections. To eliminate the external disturbance and parameter variation, an adaptive back-stepping controller with parameters estimation for a PMSLM speed control system is proposed and the detailed design procedure is discussed. The speed tracking responses with adaptive backstepping controller and PI controller are compared. The simulation results validate the proposed control method.

Dynamic Sensorless Detection of Linear Electromagnetic UAV Launch

The technical solution of Unmanned Aerial Vehicle (UAV) has the following features: good controllability; simple thrust control; high precision; long operating life; low cost; strong adaptability, repeatability, maneuverability, and imperceptibility. So the UAV has widespread application prospects. The position sensor of the mover of UAV linear electromagnetic ejection is the key component of control system. It has a direct influence on performance, structure, and reliability of the system. As the sensors such as linear photoelectric encoder and magnetic encoder are not able to meet the demand of high speed control, the paper develops the research on the detection methods of the mover position. First, the paper presents a detection method of mover position based on sliding mode observer. Due to the flicker problem of sliding mode observer, the paper then proposes a detection method based on state observer, and the method can result in smooth detected position of the mover. Finally, the simulated results of the ejection verify the validity of the proposed method.

Study on dual stator winding induction generator system based on fuzzy control

The dual stator winding structure (the power winding and compensating winding) is used to improve the dynamic performance of the induction generator. The constant output voltage of the power winding is kept through the input voltage regulation of the compensating winding. The dual stator induction generator system is controlled by a fuzzy controller for improving dynamic response. The modeling and simulation method of the fuzzy control system based on Matlab/Simulink are introduced in the paper. The simulation results show that the fuzzy control system has a faster dynamic response than that of the traditional PID controller. After changing Y801-4 induction motor to dual stator winding induction generator, the validity of dual stator winding induction generatorpsilas characteristic is proved by the results of experiment.

Research on Closed-Loop Control of Single-Phase Excited Permanent Magnet Synchronous Generator

Aiming at the characteristic of excited single-phase brushless synchronous generator, it is analyzed that the single closed-loop excitation regulator has a defect that its output voltage is reducing with increasing load. Using double closed loop speed regulation system of DC motor for reference. Design a new type regulator which has a excitation current inner loop and voltage outer loop, and use PWM method to regulate excitation current. Based on mathematic model and design target of the diesel generator and voltage regulation of generators steady and dynamic state. Current and voltage regulator are designed by typical link which is known by relation of target and parameter. The test result shows that the whole system has advantage that is regulating voltage precision and fast response. The voltage regulator is designed by engineering method, and it meets the requirements after correcting.

Research on the permanent magnet synchronous motor control system based on additional and sensing windings

The rotor position of permanent magnet synchronous motor is mostly detected by mechanical encoders, which increase the complexity and cost but reduce the reliability of the control system, moreover limit the applications of permanent magnet synchronous motor in certain special situations. In this paper, one method that can detects the rotor position, winding temperature and the rotor flux meanwhile through additional windings instead of changing motor structure is proposed. An additional winding is connected in the orientation opposite to that of the stator winding, and then a high-frequency current is injected into the winding to calculate the rotor position, sense the main motor winding temperature and the rotor flux by detecting the variations of the additional winding resistance and back electromagnetic force (EMF). Experimental results validate that the method is effective and feasible.

The study of an electromechanical actuator with a resolver as the position sensor

Space electromechanical actuator uses a permanent magnet synchronous motor as the servo component, which features in small dimension, high accuracy and reliability. At the same time the position signal of the electromechanical actuator is significant for the system performance. Resolver is widely used due to its high temperature tolerance, humidity resistance, impact resistance, anti-jamming and other advantages. In this paper, the position sensor of the electromechanical actuator servo system uses a resolver as the rotor position sensor, designes the resolver signal processing circuit that can get absolute position signal directly, and translate it into digital corresponding quantity. Decoder chip and controller chip can be linked through the data bus, I/O port and SPI port in order to interface with the digital signal processor (TMS32F2808) chip which can receive and process the signals of the rotor position. With the space vector control strategies of Permanent magnet synchronous motor, better performance has been achieved. Experiments show that the design is compact, high reliability, high precision and has achieved satisfactory results.

Research on the Nine-Phase Linear Oil Pumping Motor and the Control System

Traditional oil pumping unit has the disadvantages such as inferior controllability and low efficiency, new types of motors are researched to take the place of the conventional pumping unit. The electromagnetic oil-pumping unit driven directly by linear motor is presented in this paper. The principle of nine-phase DC linear motor is proposed, and general structure is designed. Finally the small-scale prototype motor has been manufactured and the controller with PI regulator using digital signal processing (DSP) is designed. The simulation and experimental results verify the design and control method.

The Research of a Novel Brushless DC Linear Motor for Electromagnetic Launcher

Electromagnetic launcher (EML) with advantages such as high thrust, high controllability, good reusability etc, shows promise for wide application. BLDC linear motor takes full use of the advantages of high efficiency, no excitation loss and good velocity performance as a DC motor. Based on the features of EML launcher, a novel BLDC linear motor with long primary short secondary structure is designed in this paper. The relationship between reluctance force and departure distance is studied when the mover departs from the track laterally. The prototype of the electromagnetic launcher is manufactured and investigated.