Showing 5 results for Dtc
D. Arab Khaburi,
Volume 8, Issue 2 (6-2012)
Abstract
This paper presents a comparative study on the Predictive Direct Torque Control
method and the Indirect Space Vector Modulation Direct Torque Control method for a
Doubly-Fed Induction Machine (DFIM) which its rotor is fed by an Indirect Matrix
Converter (IMC). In Conventional DTC technique, good transient and steady-state
performances are achieved but it presents a non constant switching frequency behavior and
non desirable torque ripples. However, in this paper by using the proposed methods, a fixed
switching frequency is obtained. In this model Doubly-Fed Induction Machine is connected
to the grid by the stator and the rotor is fed by an Indirect Matrix Converter. Functionally
this converter is very similar to the Direct Matrix Converter, but it has separate line and
load bridges. In the inverter stage, the Predictive method and ISVM method are employed.
In the rectifier stage, in order to reduce losses caused by snubber circuits, the rectifier fourstep
commutation method is employed. A comparative study between the Predictive DTC
and ISVM-DTC is performed by simulating these control systems in
MATLAB/SIMULINK software environments and the obtained results are presented and
verified.
H. Benbouhenni,
Volume 14, Issue 1 (3-2018)
Abstract
In this paper, the author proposes a sensorless direct torque control (DTC) of an induction motor (IM) fed by seven-level NPC inverter using artificial neural networks (ANN) and fuzzy logic controller. Fuzzy PI controller is used for controlling the rotor speed and ANN applied in switching select stator voltage. The control method proposed in this paper can reduce the torque, stator flux and total harmonic distortion (THD) value of stator current, and especially improve system good dynamic performance and robustness in high and low speeds.
M. H. Lazreg, A. Bentaallah,
Volume 15, Issue 1 (3-2019)
Abstract
This article presents a sensorless five level DTC control based on neural networks using Extended Kalman Filter (EKF) applied to Double Star Induction Machine (DSIM). The application of the DTC control brings a very interesting solution to the problems of robustness and dynamics. However, this control has some drawbacks such as the uncontrolled of the switching frequency and the strong ripple torque. To improve the performance of the system to be controlled, robust techniques have been applied, namely artificial neural networks. In order to reduce the number of sensors used, and thus the cost of installation, Extended Kalman filter is used to estimate the rotor speed. By viewing the simulation results using the MATLAB language for the control. The results of simulations obtained showed a very satisfactory behaviour of the machine.
M. Sanatgar, M. R. Alizadeh Pahlavani, A. Bali Lashak,
Volume 15, Issue 3 (9-2019)
Abstract
This paper presents the control approach for single inverter dual coupled brushless DC motors (DCBLDC) drive system. One of the basic requirements of such systems, is the power balance between two motors and on the other hand, minimizing mechanical fluctuations in order to avoid mechanical equipment damage especially in the state of mechanical resonance. This paper also presents an improved form of the conventional direct torque control (IDTC) for the DCBLDC, which can be used on nine-switch inverters (NSIs). The conventional approaches used in the coupled motors are considered, and then a combination of torque and velocity control is proposed for DCBLDC. After theoretical analysis and drive modeling, whose performance has been simulated by MATLAB/Simulink in terms of dispatching balanced power as well as dealing with transient phenomena owing to malfunctioning of the mechanical connection line. Finally, experiments with the 120W BLDC motors are executed to verify the feasibility of the proposed approach.
A. Ghayebloo, S. Shiri,
Volume 17, Issue 4 (12-2021)
Abstract
In this paper, a conceptual study on switching intervals in the classic direct torque control (DTC) method and a novel modified method have been proposed. In the switching table of classic DTC, the switching vectors have been changed in sectors with 60 degrees intervals and their boundaries are fixed. In this study, these fixed boundaries and length of switching intervals have been challenged and proved that the performance of the classic DTC can be improved with modified intervals with different lengths and boundaries. The final proposed switching table not also benefits simplicity of implementation as classic DTC switching table, but also it offers better performance especially in the aspect of low torque ripples. The proposed final switching table has been derived by a two-stage optimization process and the results have been proved by simulation results.
