Vector Control Technique Research Articles

Robust and High-Dynamic-Performance Control of Induction Motor Drive Using Transient Vector Estimator

The two most commonly used induction motor control methods are the scalar ( $V/f$ ) and vector (field-oriented) control techniques. $V/f$ control has good steady-state response and robustness against the variation in machine parameters, but the resulting torque dynamics are poorer. Vector control achieves better dynamic performance by decoupling the flux- and torque-producing components of the stator current. Vector-controlled techniques are heavily dependent on the machine parameters and are sensitive to the variation in machine parameters. This paper proposes a novel control technique, which integrates the robustness features of scalar control and good dynamic performance of vector control. Estimation of the transient vector is responsible for improving dynamics in the proposed control. The proposed control technique uses an optimal controller with an output feedback law. The operation of the proposed control is validated experimentally under both steady-state and transient conditions. Finally, the proposed control is compared with both the $V/f$ and vector control strategies in terms of dynamic performance and parameter sensitivity.

Rotor Speed Observer with Extended Current Estimator for Sensorless Control of Induction Motor Drive Systems

The aim of paper is to investigate an efficient sensorless control method with vector-control technique for the induction motor (IM) drive systems. The proposed technique relies on the indirect rotor-field orientation control scheme (IRFOC). All sensorless control techniques are greatly affected by the observation of the speed estimation procedure. So, an efficacy new algorithm for estimating the rotor speed of the adopted machine is proposed. In addition, a simple effective method to estimate the machine rotor currents is suggested. The adopted rotor-speed observer is based on the concept of IRFOC method and the phase-axis relationships of IM. To ensure the capability of the proposed sensorless speed-control system, a simulation model is developed in the MATLAB/Simulink software environment. The robustness of the new control method is analyzed under parameter uncertainty issue. Furthermore, comprehensive experimental results are obtained. The whole obtained results confirm the validity of the proposed observer for sensorless speed control capability. The given results also verify the effectiveness of the suggested sensorless control system-based IRFOC for speed-control drive systems of IM. Moreover, the results assure that the presented rotor-speed observer is effectively robust via any parameter changes.

A Multiobjective GI-Based Control for Effective Operation of PV Pumping System Under Abnormal Grid Conditions

The increasing renewable energy penetration has encouraged solar water pumping (SWP) as an effective solution to escalating water demand in remote areas. Despite receiving wide-spread popularity, such systems exhibit an unreliable operation due to intermittent weather conditions. As the utility grid integration enables the bidirectional power flow, it has emerged as a viable solution for uninterrupted pumping. However, since most of the SWP systems are remotely installed at radial ends of the distribution network, they encounter problems associated with abnormal grid conditions, which degrade their performance. A generalized integrator (GI) is used to deal with these issues. However, convention GI structures are incapable of effectively mitigating them. Therefore, a multiresonant cascaded second-order generalized integrator (MC-SOGI) based control approach is developed in this article to deal with these issues. The proposed MC-SOGI structure provides effective dc-offset rejection along with filtering of harmonics as well as subharmonics. Therefore, the proposed control approach is capable of effectively extracting the balanced fundamental positive sequence components even under unbalanced distorted grid voltages and maintaining unity displacement power factor under all conditions. An enhanced system efficiency is achieved by employing a permanent magnet synchronous motor (PMSM) for driving the pump. The well-known vector control technique and an incremental conductance algorithm are used for controlling the speed of PMSM and optimum power harvesting, respectively. The estimation of rotor speed and position is carried out by using voltage and current templates for eliminating the encoder thereby enhancing the system reliability and reducing the cost. The system performance is investigated experimentally and the acquired results validate the system feasibility.

Field Programmable Gate Array-Based Linear Shaft Motor Drive System Design in Terms of the Trapezoidal Velocity Profile Consideration

Owing to the benefits of programmable and parallel processing of the field programmable gate arrays (FPGAs), they have been widely used to the realization of digital controllers and motor drive systems. In this study, we adopt the FPGA chip to realize the Linear Shaft Motor (LSM) drive system which includes the position, speed and current vector controls. Linear shaft motor is a special motor which has the magnet as the shaft and stator coils are on the forcer. Thus, it reveals a small mechanical time constant. In addition, the electrical side can be looked as a general three-phase Alternating Current (AC) system which can be powered by inverter and vector control technique can be applied to the system. The designed system needs high performance calculation ability about position/speed control and vector current control loops. The mathematical model of linear shaft motor drive system is first built and simulated by MATLAB/Simulink and the accuracy about the effect from the speed estimation method is proposed. The resulting digital model of the drive system is stored into Verilog Hardware Description Language (Verilog HDL) codes and realized by FPGA. At last, the hardware circuits as well as the power module are used to test the performance of the developed hardware system in terms of the trapezoidal velocity profile. The experimental results show that the designed system realized by FPGA has attained the desired performance.

Benefits and limitations of emerging techniques for mosquito vector control

Benefits and limitations of emerging techniques for mosquito vector control

Lessons Learned from Dengue Surveillance and Research, Puerto Rico, 1899-2013.

Dengue was first reported in Puerto Rico in 1899 and sporadically thereafter. Following outbreaks in 1963 and 1969, the Centers for Disease Control and Prevention has worked closely with the Puerto Rico Department of Health to monitor and reduce the public health burden of dengue. During that time, evolving epidemiologic scenarios have provided opportunities to establish, improve, and expand disease surveillance and interventional research projects. These initiatives have enriched the tools available to the global public health community to understand and combat dengue, including diagnostic tests, methods for disease and vector surveillance, and vector control techniques. Our review serves as a guide to organizations seeking to establish dengue surveillance and research programs by highlighting accomplishments, challenges, and lessons learned during more than a century of dengue surveillance and research conducted in Puerto Rico.

Indirect vector control for induction motor drive using two level and five level inverter

This paper represent modelling & simulation of indirect vector control for induction motor drive using two level and five level inverter. To overcome of lower order harmonics, THD & speed torque characteristics of three phase squirrel cage induction motor. This paper provides solution through indirect vector control & SPWM technique for multilevel inverter. A comparison and performance of two level and five level inverter are used in motor to control speed, current and torque. Matlab simulation environment are taken to simulate indirect vector control for induction motor drive using two level and five level inverter, so torque ripple minimization, lower order harmonics are reduced, constant speed, constant torque and variable speed variable torque are determined through simulation results. The applications under operating conditions are performed better THD, better reliability in AC drives.

3-Phase Induction Motor Control using Space Vector and Sinusoidal Pulse Width Modulation Technique

This paper deals with the control of the induction motor using two different control methods: Space Vector and Sine wave pulse width modulation technique. The objective of the project is to find the most appropriate technique for induction motor control for industrial application. The scalar v/f method offers good performance only in the course of the steady-state and not under transient conditions. This important downside may be rectified by the vector control technique. The method provides high dynamic performance for velocity and torque-controlled AC machines.

Modeling and simulation of quasi-Z-source indirect matrix converter for permanent magnet synchronous motor drive

This paper aims to use a three-phase quasi-Z-source indirect matrix converter (QZSIMC) to expand the voltage gain for application in a Permanent Magnet Synchronous Motor (PMSM) drives. In this converter, a unique quasi-Z-source network (QZSN) connects the three-phase input voltage to conventional indirect matrix converter (IMC) in order to boost the supply voltage for PMSM because of limited voltage gain of IMC. Dual space vector modulation (SVM) is utilized to control the QZSIMC. The amplitude of output voltage for quasi-Z-source network is raised by the shoot-through of the rectifier stage, so the system voltage gain becomes greater. Through selecting the optimized value of shoot through duty ratio (<em>D</em>) and modulation index of the rectifier stage (), the drive system can automatically regulate the output voltage of QZSIMC during conditions of voltage sag , step change in load torque and reference speed change when the required voltage gain of QZSIMC is more than 0.866 depending on input voltage and required output voltage.The vector control technique based on closed loop speed control is proposed to control speed of the motor from zero to rated speed which is combined with the proposed converter to obtain the motor drive. The simulation results with MATLAB /Simulink 2015 are obtained to validate performance of PMSM drive.

Numerical study on the shock vector control in a rectangular supersonic nozzle

In recent decades, the fluidic thrust vector control technique is one of the core strategies to redirect various aerospace vehicles, such as modern launch rockets, supersonic aircraft, and guided missiles. The fundamental theory of the shock vector control is that the gas is injected into the supersonic part of a conventional convergent–divergent nozzle from the transverse to cause interactions between the shock waves and boundary layers. Then, the deflection of the primary jet can be easily realized by the induced oblique shock waves. It was evident that the shock vector control is a very simple, low weight, low cost, and quick vectoring response technique to gain high thrust vectoring performance. In the present work, computational fluid dynamics studies were performed at different control parameters in a three-dimensional rectangular supersonic nozzle with the slot injector. For the validation of the numerical methodology, computational results were compared with experimental data referred to the NASA Langley Research Center. The static pressure distributions along the upper and lower nozzle surfaces in the symmetry plane were matched with the test data excellently. Numerical simulations were based on the well-assessed shear stress transport k–ω turbulence model. Second-order accuracy was selected to reveal more details of the flow-field as much as possible. Lots of factors were investigated, such as the momentum flux ratio, length-to-width ratio, injection location, and injection angle. The performance variations for different affecting factors were illustrated and some constructive conclusions were obtained to provide the reference for further investigations in fluidic thrust vector control field.

Optimized Field Oriented Control Design by Multi Objective Optimization

Permanent Magnet Synchronous Motors are popular electrical machines in industry because they have high efficiency, low ratio of weight/power and smooth torque with no or less ripple. In addition to this, control of synchronous motor is a complex process. Vector control techniques are widely used for control of synchronous motors because they simplify the control of AC machines. In this study, Field Oriented Control technique is used as a speed controller of a Permanent Magnet Synchronous Motor. The controller must be good tuned for applications which need high performance, and classical methods are not enough or need more time to achieve the requested performance criteria. Optimization algorithms are good options for tuning process of controllers. They guarantee finding one of the best solutions and need less time for solving the problem. Therefore, in this study, Tree-Seed Algorithm is used for tuning process of the controller parameters and the results show that Tree-Seed Algorithm is good tool for controller tuning process. The controller is also tuned by Particle Swarm Algorithm to make a comparison. The results show that optimized system by Tree-Seed Algorithm has good performance for the applications which need changing speed and load torque. It has also better performance than the system which is optimized by Particle Swarm Optimization algorithm.

Application of seven-level neural space vector PWM in direct vector control system of doubly fed induction generator for wind turbine

This paper presents the direct vector control (DVC) technique of doubly fed induction generator (DFIG) with the application of seven-level neural space vector pulse width modulation (7L-NSVPWM). The mathematical model of the DFIG has been described. The descriptions of the 7L-SVPWM technique and neural networks (NNs) have been presented. The DVC control scheme with 7L-NSVPWM technique has been described. The simulation results of the DVC control with 7L-NSVPWM strategy have been performed, and the results of these simulations are presented and discussed.

Control of three-degree-of-freedom resonant actuator driven by novel vector control

This paper presents a novel vector control method for three-degree-of-freedom resonant actuator in order to improve its controllability. The effectiveness of the presented method is verified through electromagnetic field analysis using 3-D finite element method:
 Issue: A three-degree-of-freedom resonant actuator has a great potential to broaden the application range of linear oscillatory actuators because it has a lot of advantages: high efficiency, simple structure, etc. However, this actuator has low controllability because the magnetic structure of each axis is not independent.
 Aim: To establish a novel vector control technique suitable for our actuator.
 Materials and methods of the studies: Electromagnetic analysis employing 3-D finite element method.
 Results: In this study, the novel vector control theory was constructed on the basis of four-phase system. The new dq model was achieved by considering 3-D coordinate transformation. The proposed method is able to decrease the influence of thrust interference from other axis and achieved higher controllability.
 Conclusion: The results of the study will contribute to a practical use of the three-DOF resonant actuator.

Field Oriented Sliding Mode Control of Surface-Mounted Permanent Magnet AC Motors: Theory and Applications to Electrified Vehicles

Permanent magnet ac motors have been extensively utilized for adjustable-speed traction motor drives, due to their inherent advantages including higher power density, superior efficiency and reliability, more precise and rapid torque control, larger power factor, longer bearing, and insulation life-time. Without any proportional-and-integral (PI) controllers, this paper introduces novel first- and higher-order field-oriented sliding mode control schemes. Compared with the traditional PI-based vector control techniques, it is shown that the proposed field oriented sliding mode control methods improve the dynamic torque and speed response, and enhance the robustness to parameter variations, modeling uncertainties, and external load perturbations. While both first- and higher-order controllers display excellent performance, computer simulations show that the higher-order field-oriented sliding mode scheme offers better performance by reducing the chattering phenomenon, which is presented in the first-order scheme. The higher-order field-oriented sliding mode controller, based on the hierarchical use of supertwisting algorithm, is then implemented with a Texas Instruments TMS320F28335 DSP hardware platform to prototype the surface-mounted permanent magnet ac motor drive. Last, computer simulation studies demonstrate that the proposed field-oriented sliding mode control approach is able to effectively meet the speed and torque requirements of a heavy-duty electrified vehicle during the EPA urban driving schedule.

Modelling and power control of grid-connected wind energy system

Wind energy generation has attracted great interests in recent years. Doubly Fed Induction Generator (DFIG) for wind turbines are largely deployed because variable-speed wind turbines have many advantages over fixed-speed generation such as increased energy capture, operation at maximum power point, improved efficiency, and power quality. This paper presents the operation and vector control of a Doubly-fed Induction Generator (DFIG) system where the stator is connected directly to a stiff grid and the rotor is connected to the grid through bidirectional back-to-back AC-DC-AC converter. The basic operational characteristics , mathematical model of the aerodynamic system and vector control technique which is used to obtain decoupled control of powers are investigated using the software Matlab/Simulink.

Sensorless Control of Brushless Doubly-Fed Generator Using Luenberger Observer Based Wind Energy Conversion Systems

<span lang="EN-US">This paper investigates the use of Luenberger observer for sensorless power control of brushless double fed induction machine (BDFM) in wind energy conversion systems, the control strategy for flexible power flow control is developed by applying flux oriented vector control (technique), In order to estimate the rotor speed, an adaptive algorithm based on Lyapunov stability theory will be design. Finally the analyzed and simulation results in MATLAB/ Simulink platform confirmed the good dynamic performance of this new sensorless control for BDFG based variable speed wind turbines.</span>

Sensor less control of PMSM fed from three phase four switch inverter based on back EMF observer and sliding mode controller with fast reaching law

Closed Loop control of PMSM drives require rotor position and angular velocity information, the use of position sensor increases cost of the drive and increases complexity in motor construction. A position sensor less vector control technique is proposed where a back EMF observer is used to estimate motors speed and position signal. Back EMF observer method is simple and has high accuracy in estimating speed of PMSM motor. Permanent magnet synchronous motor is fed from a three-phase four-switch inverter and sliding mode controller is used as a speed regulator. Fast reaching law is added to sliding mode speed controller, which replaces constant switching gain function by variable switching function based on sliding surface. Variable switching function for SMC eliminates the chattering problem that occurs due to high value of constant switching gain. The proposed reaching law for sliding mode controller reduces the time taken for the controller to reach convergence and also increases robustness of the drive during parameter variation and full load conditions. Use of sensor less control technique and four-switch inverter reduced the overall cost of the drive whilst maintaining the performance of the system. Merits of pro-posed sensor less control technique and sliding mode controller with fast reaching law is verified by simulations using MATLAB/Simulink software.

Modelling and power control of grid connected wind energy system


 Wind energy generation has attracted great interests in recent years. Doubly-fed induction generator (DFIG) for wind turbines (WTs) are largely deployed, because variable-speed WTs have many advantages over fixed-speed generation such as increased energy capture, operation at maximum power point, improved efficiency and power quality. This paper presents the operation and vector control of a DFIG system, where the stator is connected directly to a stiff grid and the rotor is connected to the grid through bidirectional back-to-back AC–DC–AC converter. The basic operational characteristics, mathematical model of the aerodynamic system and vector control technique, which is used to obtain decoupled control of powers, are investigated using the software Matlab/Simulink.
 
 Keywords: Wind turbine, doubly-fed induction generator, active and reactive power controller.

Vector Control of VSC HVDC System under Single Line to Ground Fault Condition

<span lang="EN-US">This paper proposes a model of a VSC (voltage source converter) based Back to Back HVDC system and its control technique under fault condition. From the mathematical model of the system relationship between the controlling and the controlled variables is determined to control the system parameters. An appropriate vector control technique is used to control active and reactive power and to maintain DC link voltage. The proposed controlling unit consists of outer control loop and inner control loop which effectively damped out the system oscillation and maintains the system stability. The validity of the model and the feasibility of the control method have been proved by the simulation results. In this paper the system performance is studied under fault condition is studied.</span>

Successes and failures of sixty years of vector control in French Guiana: what is the next step?

Since the 1940s, French Guiana has implemented vector control to contain or eliminate malaria, yellow fever, and, recently, dengue, chikungunya, and Zika. Over time, strategies have evolved depending on the location, efficacy of the methods, development of insecticide resistance, and advances in vector control techniques. This review summarises the history of vector control in French Guiana by reporting the records found in the private archives of the Institute Pasteur in French Guiana and those accessible in libraries worldwide. This publication highlights successes and failures in vector control and identifies the constraints and expectations for vector control in this French overseas territory in the Americas.