Improved sensorless EKF-based direct torque control at low speed with constant switching frequency controller

2014 ◽  
Author(s):  
I.M. Alsofyani ◽  
N. R. N. Idris
Keyword(s):  
Direct Torque Control ◽  
Torque Control ◽  
Switching Frequency ◽  
Low Speed ◽  
Frequency Controller

Research on Induction Motor DTC System Based on Fuzzy PI Controller

2010 ◽  
Vol 29-32 ◽  
pp. 2200-2204
Author(s):  
Xue Zhi Hu ◽  
Guang Qun Nan
Keyword(s):  
Induction Motor ◽  
Direct Torque Control ◽  
Experimental System ◽  
Torque Ripple ◽  
Torque Control ◽  
Switching Frequency ◽  
System Effect ◽  
Low Speed ◽  
Static Performance ◽  
Stator Flux

Traditional induction motor direct torque control system with the hysteresis loop controller, based on torque error, set the amplitude error to select the inverter switching state, is a Band-Band Control , torque error and stator flux error of level can not be distinguished, switching frequency is not constant, over-sector current and the distortion flux linkage can product low speed torque ripple, affecting the control of the system effect. The paper proposed fuzzy PI control of induction motor direct torque control scheme, a system of principles was introduced, controller parameters was designed by fuzzy theoretical. Finally a full-digital experimental system was built with the TMS320F2812 as the master chip and PM30CSJ060 as an inverter main circuit. Results show that the dynamic and static performance and running smoothly with low-speed is verified.

scholarly journals An Efficient of Direct Torque Control of Indirect Three Level Matrix Converter Fed Dual Stator Induction Motor Based on Synergetic Controller

2020 ◽  
Vol 53 (5) ◽  
pp. 617-627
Author(s):  
Yahia Moati ◽  
Katia Kouzi
Keyword(s):  
Control Strategies ◽  
Direct Torque Control ◽  
Torque Ripple ◽  
Matrix Converter ◽  
Torque Control ◽  
Switching Frequency ◽  
Outer Loop ◽  
Speed Regulation ◽  
Control Scheme ◽  
Frequency Controller

As know, Direct Torque Control (DTC) suffers from the high ripples of the torque and flux, caused by the variable switching frequency. Torque ripple in DTC drives can be reduced if an Indirect Three-Level Matrix Converter (ITLMC) is employed instead of a conventional Two-Level Indirect Matrix Converter. Nevertheless, this problem can be still large if low switching frequencies are used. In order to overcome this problem, a Constant Switching Frequency controller (CSFC) is proposed to replace the five-level hysteresis torque comparator for reducing the ripples and improving the flux regulation in low and zero speed operation. Furthermore, the control scheme performance is enhanced by inserting a robust Synergetic Controller (SC) in the outer loop for speed regulation. Simulation results with a comparative analysis have indicated the special merit of the proposed scheme, which makes it competitive with the existing control strategies.

scholarly journals Direct Power Control of Matrix Converter-Fed DFIG with Fixed Switching Frequency

2019 ◽  
Vol 11 (9) ◽  
pp. 2604 ◽  
Author(s):  
Arzhang Yousefi-Talouki ◽  
Shaghayegh Zalzar ◽  
Edris Pouresmaeil
Keyword(s):  
Power Control ◽  
Direct Torque Control ◽  
Matrix Converter ◽  
Torque Control ◽  
Switching Frequency ◽  
Direct Power ◽  
Direct Power Control ◽  
Reactive Component ◽  
Extensive Discussion ◽  
Induction Generators

In this paper, a direct power control (DPC) technique is proposed for matrix converter-fed grid-connected doubly fed induction generators (DFIGs). In contrast to what has been investigated in the past for direct torque control (DTC) or DPC of matrix converter-fed DFIGs, the active and reactive powers are regulated in a fixed switching frequency using indirect space vector modulation (ISVM) technique. Hence, designing input filters for matrix converters (MCs) becomes convenient. In addition, the reactive component of input side of MC is controlled which leads to reduction of distortion in grid current waveform. Also, an extensive discussion is addressed for nonlinear voltage errors of MC that may cause inaccurate power control. Simulation results done in MATLAB/Simulink show the effectiveness of the proposed method.

Sensorless finite-state predictive torque control of induction motor fed by four-switch inverter using extended Kalman filter

2018 ◽  
Vol 37 (6) ◽  
pp. 2006-2024 ◽  
Author(s):  
Mohamed Chebaani ◽  
Amar Goléa ◽  
Med Toufik Benchouia ◽  
Noureddine Goléa
Keyword(s):  
Kalman Filter ◽  
Induction Motor ◽  
Extended Kalman Filter ◽  
Direct Torque Control ◽  
Operating Conditions ◽  
Torque Control ◽  
Switching Frequency ◽  
Content Type ◽  
Finite State ◽  
Torque Ripples

Purpose Direct Torque Control (DTC) of induction motor drives is a well-established technique owing to features such as fast dynamic and insensibility to motor parameters. However, conventional DTC scheme, based on comparators and the switching table, suffers from large torque and flux ripples. To improve DTC performance, this study aims to propose and implement a sensorless finite-state predictive torque control using extended Kalman Filter in dSPACE environment. Design/methodology/approach This paper deals with the design of an extended Kalman filter for estimating the state of an induction motor model and for sensorless control of systems using this type of motor as an actuator. A complex-valued model is adopted that simultaneously allows a simpler observability analysis of the system and a more effective state estimation. Findings Simulation and experimental results reveal that the drive system, associated with this technique, can effectively reduce flux and torque ripples with better dynamic and steady state performance. Further, the proposed approach maintains a constant switching frequency. Originality/value The proposed speed observer have been developed and implemented experimentally under different operating conditions such as parameter variation, no-load/load disturbances and speed variations in different speed operation regions.

Study on speed sensorless system of permanent magnet synchronous motor based on improved direct torque control

2021 ◽  
pp. 014233122110629
Author(s):  
Xiaoxin Hou ◽  
Mingqian Wang ◽  
Guodong You ◽  
Jinming Pan ◽  
Xiating Xu ◽  
...  
Keyword(s):  
Control System ◽  
Permanent Magnet ◽  
Permanent Magnet Synchronous Motor ◽  
Direct Torque Control ◽  
Torque Ripple ◽  
Synchronous Motor ◽  
Torque Control ◽  
Switching Frequency ◽  
Speed Sensorless ◽  
Stator Resistance

The traditional direct torque control system of permanent magnet synchronous motor has many problems, such as large torque ripple and variable switching frequency. In order to improve the dynamic and static performance of the control system, a new torque control idea and speed sensorless control scheme are proposed in this paper. First, by deriving the equation of torque change rate, an improved torque controller is designed to replace the torque hysteresis controller of the traditional direct torque control. The improved direct torque control strategy can significantly reduce the torque ripple and keep the switching frequency constant. Then, based on the improved direct torque control and considering the sensitivity of the stator resistance to temperature change, a speed estimator based on the model reference adaptive method is designed. This method realizes the stator resistance on-line identification and further improves the control precision of the system. The performance of the traditional direct torque control and the improved direct torque control are compared by simulation and experiment under different operating conditions. The simulation and experimental results are presented to support the validity and effectiveness of the proposed method.

Research on Indirect Stator-Quantities Sliding Model Control for Induction Motor

2011 ◽  
Vol 291-294 ◽  
pp. 2871-2874
Author(s):  
Li Hua Zou
Keyword(s):  
Induction Motor ◽  
Direct Torque Control ◽  
Torque Ripple ◽  
Torque Control ◽  
Frequency Error ◽  
Model Control ◽  
Stable Performance ◽  
The Stability ◽  
Slip Frequency ◽  
Frequency Controller

In direct torque control system for induction motor, the system has big torque ripple and strong noise caused by torque ripple. In indirect stator-quantities control, a slip frequency controller, based on power frequency exponent integration reaching law sliding model, is adopted by using practical measure velocity and calculation torque of motor flux model. The slip frequency error is fast convergent and stable in the nearby zero value, the method reduces torque ripple and improve dynamic and stable performance. The stability analysis of the scheme is given by using Lyapunov method. The simulation results verify the effectiveness and correctness of the method.

Sign in / Sign up

Export Citation Format

Share Document