Direct Torque Control Technology Research Articles

Direct torque motor control technology based on NPC three-level SVPWM

This paper introduces a direct torque control technology based on NPC three-level SVPWM. It uses the Matlab platform to build a simulation model. It verifies the ideal waveform of the torque, magnetic chain, and current of the NPC-SVPWM direct torque control system under high speed and low speed with no load and load. This technique improves the waveform of the stator current and stator magnetic chain and solves the problem of the switching frequency not being fixed. Through this technique, it not only retains the robustness of the direct torque technique to the parameter change, but also effectively reduces the torque pulsation.

Optimum Design and Control of Marine Permanent Magnet Synchronous Motor

Marine electric propulsion has the advantages of wide range of speed regulation, easy installation and flexible operation’ so it is a high performance propulsion and superior in many respects compared with mechanical propulsion. Permanent magnet synchronous motor (PMSM) has a series of advantages such as fast response speed, strong overload capacity, high power density and high efficiency, so it is very suitable for marine propulsion system. In this paper, a kind of marine permanent magnet synchronous motor was optimized by using Maxwell software. At the same time, the direct torque control technology was simulated by using mathematical modelling. Direct torque control (DTC) is a high performance AC speed regulation technology. As long as the appropriate voltage vector is selected, the system can be controlled to quickly follow the given speed and adapt to the change of torque. The simulation results show the good performance for the marine permanent magnet synchronous motor in this paper so that it can fully meet the requirements in both speed characteristics and torque characteristics.

Research on Direct Torque Control of Doubly-Fed Generator Based on DSP Technology

Doubly-fed VSCF wind power generator has become the main machine because it can improve the efficiency of wind power and obtain the optimal energy output at rated wind speed. In the control of excitation on double fed generator,the technique of direct torque control become the mostly method.This paper adopts voltage space vectors subdivision technology of direct torque control technology that can improve the low frequency characteristic,and structure the experiment system based on DSP. The result indicated the project is feasiblIntroduction Wind power as a kind of green energy has attracted more and more attention. in recent years, wind power technology has made rapid development. Double-fed generator becoming the main type of wind power generator because of its capture wind energy efficiency at rated wind speed. At present, foreign countries have successfully applied direct torque control ( DTC ) technique in VSCF doubly-fed wind power generator, Whereas DTC exist the problems of low frequency excitation current aberrance and output torque ripple. Therefore, this paper puts forward the space vectors subdivision method to improve the low-frequency characteristicbased on the traditional direct torque control of doubly-fed generator, And structure the doubly-fed generator direct torque control experimental platform about the digital signal processor ( DSP ), realize the grid-connected power generation.

The Novel Control Technologies Used in Permanent Magnet Synchronous Motor

In order to improve the torque control performance of permanent magnet synchronous motor, variable frequency variable speed control technology, vector control technology, direct torque control technology and sensorless control technology were analyzed. The fuzzy + PID control technology used in permanent magnetic synchronous motor was introduced in detail. The conventional sliding mode observer based on the counter electromotive force estimate control technology and the structure of improved sliding mode observer was given separately. The fuzzy + PID control technology and improved sliding mode observer control technology proposed could improve the dynamic performance and static performance of the permanent magnet synchronous motor.

The Technology Study of Direct Torque Control Method for Permanent Magnet Synchronous Motor

According to the analysis of mathematical model for permanent magnet synchronous motor (PMSM), direct torque control(DTC) technology is introduced to the control system of PMSM. The paper builds dual-closed loop control system of PMSM, and the outer loop is speed loop, the inner loop is flux and torque loop, at the same time, the paper makes simulation in Matlab/Simulink. The simulation results show that the DTC technology significantly improves the dynamic performances of PMSM, and the control system is no overshoot, and has small flux response comparing with the conventional control methods of PMSM. So the application of DTC technology in PMSM provides a new thoughtful way for PMSM control system designing and debugging in actual application.

Improving Reliability and Productivity of an Aluminum Extruder by Implementation of Direct Torque Control Technology

Problem statement: The linear motor drive is widely used in driving an extrusion puller in an aluminum extrusion industry. The main disadvantage of this drive is manual and step-wise torque control. This research was done to replace the linear motor drive by AC drive with direct torque control technology. Approach: Mathematical calculations were carried to select an AC drive which satisfied parameters and values required for production process. Motor rotational speed and torque were calculated from required linear velocity of puller machine and pulling force required for extruded aluminum sections. Results: The suggested AC drive with direct torque control was implemented and installed. It proved higher reliability due to elimination of mechanical problems and wears. Higher productivity was obtained due to flexibility and automation of speed and torque control modes. Conclusion/Recommendations: Implementation of AC drive with direct torque control led to savings in electrical energy consumption, reduction in breakdown and maintenance intervals and improvement of product quality. AC drive with direct torque control was suggested to replace other drive types in all industrial applications were torque and speed modes of control were required.

Direct torque control of synchronous motor drives for dynamically demanding applications

This paper proposes a new concept for the Direct-Torque-Control (DTC)-based synchronous machine drive. DTC technology provides a synchronous machine drive with excellent dynamic properties. The DTC principles are first briefly recalled. The study observes the problem of the flux linkage integration instability and introduces the flux linkage estimate correction method based on the current model. The field winding current control methods are analysed. It is shown that a synchronous machine drive also needs a stabilisation method when working with very high load angles especially in the field weakening range. A method to control the load angle directly is then proposed. Test results with a 14.5-kVA laboratory prototype drive are given.