Huang Shenghua

Study on speed detection and control method of PMSM under ultra-low speed

The mathematical model of permanent magnet synchronous motor (PMSM) and the digital control method of current loop have been studied, including P regulator, P regulator plus feed forward control and PI regulator. And PI has the best performance. Under ultra low speed, the coupling of d axis current and q axis current do not exist, so the speed control system become a single input and single output system. The speed detection problem of PMSM has been studied also in this paper. The method of T and M/T speed detection will deteriorate the performance of the servo system under ultra-low speed. The M method is suitable for high speed and low speed range both. The deference of PLL and M speed detection method has been studied also. System software flowchart using TMS320F2812 is presented. The experiment results are given, and the validity of this theory is proved.

Induction compensation control of bearingless induction motor

Analysis and contrast between air-gap flux orientation and rotor flux orientation of bearingless induction motor are be given firstly, at the same time, the flux orientation control strategy and induction compensatation method of magnetic suspension system are analyzed. Then, according to the operation characteristics of bearingless induction motor, the combined control strategy is selected, i.e., rotor flux orientation strategy will be adopted for four-pole torque system and air-gap flux orientation and induction compensation control strategy will be adopted for two-pole magnetic suspension system, and the simulation and experiment of decouple control system of three-phase bearingless induction motor have been made. The simulation and experiment results have proved the validation of the united control strategy.

Models and Developing of Load Torque Simulator with Permanent Magnet Synchronous Motor for Ship Electric Propulsion

This paper has first elaborated the background, purposes and importance of the selected subject as well as briefly introduced the types of submarine drive motor load. Drive motor load characteristic simulation principle is the foundation of designing simulation controller. Sets up PMSM-DC generator unit, Based on it, the armature current of dynamic load simulation system has been designed. Meanwhile, the problems with the theories and techniques of simulation engines are solved. Next on the foundation of advancing and analyzing the permanent magnet synchronous motor load characteristic simulate dynamic model, build a base on TMS320LF2407DSP simulation controller of load system, and the experiment result was showed

A three phase ZVS bidirectional DC-DC converter

The purpose of the article is to introduce a new DC-DC converter typology, which has the advantages of simple circuit typology with no total device rating penalty, soft-switching implementation without additional devices, simple control and low cost. It is promising for medium and high power applications where high power density, low cost and high reliability power converters are required, such as fuel cell vehicles. We work on the three phase typology, including the phase shift control principles, the phase shift control strategy, soft switching realization conditions and method. By computer simulation and experiment, the theoretical results can be verified or modified. Finally, the simulation and experiment results are presented.

Hardware implement of numerical control system for bearingless induction motor

To realized the numerical control of three-phase bearingless induction motor, the unitary configuration of numerical control experimental system of three-phase bearingless induction motor has been designed firstly, then based on TMS320LF2407A numerical control CMOS chip of motor, the hardware control system configuration has been designed, and aiming at DSP operation and controller, high-speed photoelectricity seclusion and drive circuit, measuring and adjusting circuits for current and radial displacement, keyboard and display numerical control circuit, etc…, have been presented. The suspension control experiment results have verified the feasibility and practicability of the designed system.

The research of battery model and intelligent charging in the rail transport system

This paper introduces a third-order dynamic model for lead acid battery whose parameters vary with the state of charge (Soc), charge current and the electrolyte temperature(θ). According to the practical dynamic model, this paper also proposes two control structure for charging battery applying to constant current and constant voltage mode: i) a innovative third closed loops control strategy composed of innermost inductance current loop, inner battery current loop and outer battery voltage loop based on the DC/DC converter, ii) a novel double closed loops control strategy composed of inner current loop and outer either battery current loop under constant current mode or battery voltage loop under constant voltage mode based on the three-phase voltage-sourced PWM rectifier. Moreover, the variable proportional-integral (PI) controller and the power feed-forward control strategy are used on PWM rectifier. The simulation and experiments are carried out to prove the performance of the battery model that shows a good compromise between complexity and precision and the feasibility of the system.

A stator resistance compensator for a direct torque controlled low speed and high torque permanent magnet synchronous motor

Nowadays, the research on low speed and high torque permanent magnetic synchronous machine more and more attention in the fields of motors, and has great science significance and application value. Direct torque control (DTC) has become an a accepted advanced control method beside the current vector control Although DTC was initially applied in asynchronous machines, but it has been introduced successfully to synchronous machines. This paper will discuss the DTC in the PMSM. With DTC, the electromagnetic torque and stator flux can be estimated using the measured stator voltages and currents. The estimation does depend on motor parameters except for the stator resistance. The variation of stator resistance due to changes in temperature or frequency degrades the performance of DTC controller by introducing errors in the estimated flux linkage vector and the electromagnetic torque. Compensation for the effect of stator resistance variation then becomes necessary. Estimation of the stator resistance and its compensation using a PI-fuzzy estimation has been proposed in this paper.

Determination of PMSM Parameters from Simple Load Test

This paper describes a method of determination of permanent magnet synchronous machines (PMSM) parameters using simple load test combination with a linear regression model, which can avoid the disadvantages of the traditional load test. In the test, only supply phase voltage, phase current and the rotor position would be required, then the linear regression model was improved to simplify algorithm using QR decompose of matrix. The parameters including e0, R, Ld and Lq obtained by using this technique vary more smoothly, while results obtained by no load test are fluctuating. This method can be used to derive the nonlinear parameter identified model of PMSM in order to apply in an on-line computer controlled environment at the different operating conditions

A Direct Torque Controlled Permanent Magnetic Synchronous Motor System Based on the New Rotor Position Estimation

The low speed and high torque permanent magnetic synchronous motor (PMSM) is increasingly playing an important role in electric propulsion system due to its many advantages over competing technologies. The direct torque control (DTC) technique for PMSM is receiving increasing attention due to the important advantages the low dependence on motor parameters when compared with other motor control techniques. But for successful operation of PMSM, rotor position and speed information is required. Thus, there has been an intense interest in the development of a so called position sensorless drive. In this paper, a adaptive estimation approach is developed which enable sensorless operation of the PMSM . Implementation issues for the sensorless PMSM electric drive are discussed,and experimental results are presented in order to demonstrate the effectiveness of the proposed techniques to the sensorless PMSM.

The adaptive control of three-degrees-of-freedom spherical motor

This paper presents the electromagnetic model and the mechanical model of three-degrees-of-freedom spherical motor (3DOFSM). The vector control and disturbance torque observer can realize the electromagnetic decoupling and mechanical decoupling control of the 3DOFSM. The adaptive scheme is proposed to improve the robustness and the dynamic performance. The correctness of the control scheme are confirmed by simulation results.