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Design and implementation of a predictive controller for reducing the torque ripple in direct torque control based high frequency induction motor drives
, Article 2004 IEEE 35th Annual Power Electronics Specialists Conference, PESC04, Aachen, 20 June 2004 through 25 June 2004 ; Volume 2 , 2004 , Pages 1169-1174 ; 02759306 (ISSN) ; Zolghadri, M. R ; Roye, D ; Guiraud, J ; Schanen, J. L ; Sharif University of Technology
2004
Abstract
In Direct Torque Control, selection of each voltage vector is based on the measured parameters in the beginning of the sampling period. Due to the fast dynamic of torque, this delay causes an extra torque ripple. In this paper, a new predictive controller is proposed for compensating this delay and reducing the torque ripple. The stator current is measured in the beginning of each sampling period and its expected value in the end of period is predicted according to an extrapolation algorithm. This algorithm is performed by calculating the slope of stator current variation according to the stator flux variation. Thus, there is no need to solve the high order equations of machine. The...
Design and implementation of a predictive controller for reducing the torque ripple in direct torque control based induction motor drives
, Article 2004 IEEE 35th Annual Power Electronics Specialists Conference, PESC04, Aachen, 20 June 2004 through 25 June 2004 ; Volume 1 , 2004 , Pages 476-481 ; 02759306 (ISSN) ; Zolghadri, M. R ; Roye, D ; Guiraud, J ; Crebier, J. C ; Sharif University of Technology
2004
Abstract
In Direct Torque Control, selection of each voltage vector is based on the measured parameters in the beginning of the sampling period. Due to the fast dynamic of torque, this delay causes an extra torque ripple. In this paper, a new predictive controller is proposed for compensating this delay and reducing the torque ripple. The stator current is measured two times at the beginning of each sampling period and its expected value at the end of period is predicted according to an extrapolation algorithm. Thus, there is no need to machine parameters and the algorithm is quite robust against machine parameters variations. The calculation of the electromagnetic torque is performed using the...
Saturation and its application in the vibration control of nonlinear systems
, Article Proceedings of the 7th Biennial Conference on Engineering Systems Design and Analysis - 2004, Manchester, 19 July 2004 through 22 July 2004 ; Volume 2 , 2004 , Pages 93-100 ; 0791841731 (ISBN); 9780791841730 (ISBN) ; Ghorashi, M ; Sharif University of Technology
American Society of Mechanical Engineers
2004
Abstract
An investigation on the nonlinear vibrations of a system with two degrees of freedom when subjected to saturation is presented. The method is especially applied to a system that consists of a DC motor with a nonlinear controller and subjected to a harmonic forcing voltage. Approximate solutions are sought using the method of multiple scales. Also, singular point analysis is used to study stability of solutions. These findings are then compared with the corresponding numerical results. Good agreement between the two is observed
The role of multisensor data fusion in neuromuscular control of a sagittal arm with a pair of muscles using actor-critic reinforcement learning method
, Article Technology and Health Care ; Volume 12, Issue 6 , 2004 , Pages 425-438 ; 09287329 (ISSN) ; Parnianpour, M ; Lucas, C ; Sharif University of Technology
IOS Press
2004
Abstract
In this study, we consider the role of multisensor data fusion in neuromuscular control using an actor-critic reinforcement learning method. The model we use is a single link system actuated by a pair of muscles that are excited with alpha and gamma signals. Various physiological sensor information such as proprioception, spindle sensors, and Golgi tendon organs have been integrated to achieve an oscillatory movement with variable amplitude and frequency, while achieving a stable movement with minimum metabolic cost and coactivation. The system is highly nonlinear in all its physical and physiological attributes. Transmission delays are included in the afferent and efferent neural paths to...
Analysis of torsional vibrations on the resolver under eccentricity in pmsm drive system
, Article IEEE Sensors Journal ; Volume 22, Issue 22 , 2022 , Pages 21592-21599 ; 1530437X (ISSN) ; Feizhoseini, S ; Nasiri Gheidari, Z ; Behzad, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Since any error in the rotor angle caused by the resolver affects the entire permanent magnet synchronous motor (PMSM) control drive system, it is necessary to investigate its effect on mechanical vibrations. Torsional vibration is accordingly considered in the following study. Thereby, first, the effect of resolver errors on the harmonic content of motor current and, subsequently, torque ripple (TR) was investigated. Then, dynamical modeling is done for the generator-motor-resolver set to get the mechanical frequency response (FR) resulting from the resolver errors. Based on the above modeling, the dynamic equations (DEQs) of the system were derived, and the mechanical characteristics of...
Improved design of an outer rotor six-phase induction motor with variable turn pseudo-concentrated windings
, Article IEEE Transactions on Energy Conversion ; Volume 37, Issue 2 , 2022 , Pages 1020-1029 ; 08858969 (ISSN) ; Tahami, F ; Capolino, G. A ; Nasiri Gheidari, Z ; Henao, H ; Sahebazamani, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
In this paper, a novel six-phase outer rotor induction motor equipped with pseudo-concentrated windings is introduced as a robust, reliable, and low-cost solution. Multiple aspects of the proposed motor structure have been investigated such as a design algorithm and an analytical modeling based on the modified winding function considering the skew effect. The effect of using variable number of turns for the coils has been examined on the pseudo-concentrated windings. An appropriate optimization problem has been also defined to maximize the power factor and efficiency and to minimize the output torque ripple. The designed motor has been fabricated to verify the accuracy of the design...
Sensor fault-tolerant scheme for IPM synchronous motor drives via nonlinear observer
, Article AUPEC'09 - 19th Australasian Universities Power Engineering Conference: Sustainable Energy Technologies and Systems, 27 September 2009 through 30 September 2009, Adelaide ; 2009 ; 9780863967184 (ISBN) ; Farshidnia, A ; Keivanian, R ; Sharif University of Technology
Abstract
This paper describes a control scheme that allows an IPMS motor drive system to operate in the event of current and speed sensor faults. This task can be achieved by two control strategies: a nominal performance controller and a fault detection part. The nominal controller combines field oriented control and addresses fault tolerance scheme. Fault-tolerant strategy will operate in parallel with the system until a fault is detected. This approach is based on the adaptive backstepping observer. Stator resistance as possible source of system uncertainty is taken into account under different operating conditions. Sensors failure are detected and developed observer is used to estimate currents...
Implementation and Analysis of Thermal Model of High Voltage Induction Motors
, M.Sc. Thesis Sharif University of Technology ; Oraee Mirzamani, Hashem (Supervisor)
Abstract
Today, various industries rely on high-power, high-voltage induction motors for diverse applications. Given the critical role these motors play, any reduction in their lifespan or occurrence of failures can lead to substantial financial losses and even pose risks to lives. One significant factor influencing motor life is the temperature of its components. Manufacturers strive to enhance motor power while minimizing dimensions for economic reasons, but this increases power density and subsequent losses, elevating motor temperature. Consequently, thermal analysis becomes crucial, posing a significant challenge for companies producing high-power induction motors. In this study, a thermal model...
Comparing different rotor structures in superconducting synchronous motors
, Article Proceedings of the 2013 IEEE International Electric Machines and Drives Conference ; May , 2013 , Pages 1053-1057 ; 9781467349758 (ISBN) ; Yaghoobi, J ; Yazdanian, M ; Zolghadri, M. R ; Ferdowsi, M ; Sharif University of Technology
2013
Abstract
Two major structures for rotor core of superconducting synchronous machine are air-cored and magnetic-cored structures. Magnetic-cored structure can be divided into two categories including salient and non-salient magnetic core. In this paper, three different structures of superconducting synchronous machine comprising air-cored, non-salient magnetic-cored and salient magnetic-cored, have been studied and compared considering required superconducting wire and machine weight. Required superconducting wire determines the capital cost and the weight of the machine determines the running cost in the case of portable applications such as ships and aircrafts
A mixture of modular structures to describe human motor planning level: A new perspective based on motor decomposition
, Article 2011 18th Iranian Conference of Biomedical Engineering, ICBME 2011 ; 2011 , Pages 199-204 ; 9781467310055 (ISBN) ; Andani, M. E ; Fattah, A ; Parnianpour, M ; Sharif University of Technology
Abstract
A modular hierarchical structure is developed to describe human movement planning level. The modular feature of the proposed model enables it to generalize planning a task. The movements are planned based on decomposing a task into its corresponding subtasks (motion phases). There is a module responsible for one condition. The final plan is constructed using soft computing of the plans proposed by different modules. Each module estimates the kinematics of the joints at the end of each subtask; we call them kinematic estimator modules (KEMs). A timing module estimates the duration of motion and a gating module determines the responsibility of each KEM under different conditions. To evaluate...
Conceptual design of a miniaturized hybrid local actuator for Minimally Invasive Robotic Surgery (MIRS) instruments
, Article Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS ; 2011 , Pages 2140-2143 ; 1557170X (ISSN); 9781424441211 (ISBN) ; Mirbagheri, A ; Farahmand, F ; Sharif University of Technology
Abstract
The actuation mechanism of the tip of an endoscopic instrument is a major problem in designing miniature scale motorized instruments, especially when a high level of functionality and multi degrees of freedom (DOF) are concerned. We evaluated the different possible actuation methods for an endoscopic needle holder and proposed a new design of hybrid local-actuation, including a micro DC motor and a piezoelectric (PZT) actuator. The DC motor provided the long movement course required for opening-closing function of the gripper while the PZT guaranteed the high gripping force required for holding the needle. A compact serial configuration was considered for the actuators, producing an overall...
Simulation and experimental validation of flow-current characteristic of a sample hydraulic servo valve
, Article Scientia Iranica ; Volume 17, Issue 5 B , 2010 , Pages 327-336 ; 10263098 (ISSN) ; Seifi, R ; Saadat Foumani, M ; Sharif University of Technology
2010
Abstract
This paper presents a novel model to simulate the flow-current characteristic curve of an electro-hydraulic servo valve in steady state condition. This characteristic curve has three major zones: dead zone, linear zone and saturation zone. By using the presented approach, we can simulate the behavior of all types of valves including under lapped, critical center (zero lapped) and over lapped valves. A hydraulic tester has been designed and constructed for validation of the results. It can test the performance of flow-current and some other properties of the valve. Comparison of experimental and simulated curves describes that the model has an acceptable accuracy in determining the four...
Heat transfer enhancement in annular flow with outer grooved cylinder and rotating inner cylinder: review and experiments
, Article Applied Thermal Engineering ; Volume 120 , 2017 , Pages 257-268 ; 13594311 (ISSN) ; Nakhchi, M. E ; Sharif University of Technology
Abstract
This experimental work is an attempt to identify the most significant parameters influencing heat transfer enhancement in annular flow with outer grooved cylinder and rotating inner cylinder. This type of flow known as Taylor-Couette flow has many industrial applications such as electrical power generators and rotating machineries. A comprehensive review of the previous works on flow regimes, heat transfer and pressure drop in grooved channels is provided. The experiments are conducted based on four different factors including Taylor number, 0
Fuzzy pole placement for speed control in D.C. motor
, Article Recent Advances in Electrical and Electronic Engineering ; Volume 11, Issue 1 , March , 2018 , Pages 15-20 ; 23520965 (ISSN) ; Mohammad Shahri, A ; Mousavi Mashhadi, S .K ; Samsaam, S ; Sharif University of Technology
Bentham Science Publishers B.V
2018
Abstract
Background: in this paper, fuzzy pole placement control approach is proposed to control the speed of D.C motor. In this method, state feedback gain is tuned by fuzzy logic. Methods: In conventional pole placement control, constant gain is considered to insert the poles of system in the desired place. Therefore, unnecessary effort is appliedto the system, and the system implementation becomes costly. In contrast, in fuzzy pole placement control, poles of system alter gradually based on the performance of system and are settled in desired point causing the system to display apposite performance. In other words, in conventional pole placement, a determined pair of poles exists, whereas in fuzzy...
Design, analysis, and fabrication of a direct drive permanent NdFeB magnet synchronous motor for precision position control
, Article IET Electric Power Applications ; Volume 14, Issue 8 , 2020 , Pages 1438-1445 ; Damaki Aliabad, A. A ; Ghafarzadeh, M ; Shamlou, S ; Sharif University of Technology
Institution of Engineering and Technology
2020
Abstract
Direct drive motors have the excellent ability for precision position control due to their direct connection to load and elimination of the gearbox and pulley backlash. Among the direct drive motors, permanent NdFeB magnet synchronous motors (PMSMs) are the best choice for control systems due to their high efficiency, high power density, good dynamic behaviour, and excellent controllability. This study deals with the design, analysis, and fabrication of a direct drive PMSM for precision position control. To reach this aim, the designed motor should have very low cogging torque and torque ripple to avoid the motor deviation at the target point. To achieve these purposes, at first, a suitable...
Probabilistic voltage harmonic analysis of direct torque controlled induction motor drives
, Article IEEE Transactions on Power Electronics ; Volume 21, Issue 4 , 2006 , Pages 1041-1052 ; 08858993 (ISSN) ; Vahdati Khajeh, E ; Zolghadri, M. R ; Sharif University of Technology
2006
Abstract
In high frequency motor-drives such as direct torque controlled (DTC) induction motor drives, the motor harmonic loss, and electromagnetic interference are largely affected by the spectrum of the motor input voltage. Nonlinear elements in the control loop of DTC drive make harmonic analysis of the drive very complex compared to classical pulsewidth modulated controlled drives. In this paper, a probabilistic method to study the harmonic contents of voltage in DTC of induction motors is presented. The DTC voltage chain is simulated with a random process. Then, the autocorrelation function of voltage vectors is calculated and its power spectrum density is obtained. The effect of flux and torque...
Validation of the driver's angry thoughts questionnaire (DATQ) in a sample of professional drivers in iran
, Article IATSS Research ; Volume 46, Issue 3 , 2022 , Pages 370-379 ; 03861112 (ISSN) ; Nassiri, H ; Sullman, M. J. M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Aggressive driving has emerged as one of the most studied behaviors in the traffic safety field, due to its association with the odds of motor vehicle crashes and especially fatal crashes. Previous research has investigated the situations which provoke anger while driving, as well as the emotional (anger) and behavioral (aggression) aspects of aggressive driving. However, surprisingly the cognitive aspects of aggressive driving have largely been neglected. This study investigated the psychometric properties of the short-forms of the Driver's Angry Thoughts Questionnaire (DATQ) and the Driving Anger Expression Inventory (DAX) in a sample of professional drivers. Furthermore, the study aimed...
A low-cost linearized analog resolver-to-DC converter
, Article 30th International Conference on Electrical Engineering, ICEE 2022, 17 May 2022 through 19 May 2022 ; 2022 , Pages 619-623 ; 9781665480871 (ISBN) ; Khajueezadeh, M ; Nasiri Gheidari, Z ; Sheikhaei, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
High-efficiency Permanent Magnet Synchronous Motors (PMSMs) are widely used in industry. Subsequently, resolvers' employment is increasing in the drive of PMSMs. Measuring the rotor angle using a resolver needs a costly Resolver to Digital Converter (RDC). Therefore, a low-cost analog RDC is designed against the conventional Angle Tracking Observers (ATOs) in the following study. The designed RDC has satisfactory accuracy, simplicity, and enduring against excitation frequency. Firstly, an overview of the resolver is shown, and subsequently, the circuit of the designed RC is described thoroughly. Ultimately, the simulations' outcomes are displayed, and comparing our design with others...
Study of Net Current of Particles in 2D Pulsated Potential Landscape
, M.Sc. Thesis Sharif University of Technology ; Ejtehadi, Mohammad Reza (Supervisor)
Abstract
In systems possessing spatial or dynamical symmetry breaking, Brownian motion combined with unbiased external input signals, deterministic and random alike, can assist directed motion of particles at nanoscale. “Brownian motors” are devices by whi thermally or extrinsically activated processes are controlled and used to generate directed motion in space. Rectification devices involving asymmetric substrates are termed ratets and if the potential priodically turns on and off in time, it is called “Pulsated Ratet.“ In this resear net current of particles in 2D pulsated asymmetric potential landscapes is surveyed theoretically and by
Monte Carlo method simulation
Monte Carlo method simulation
Design of a Charging Station for Evs
, M.Sc. Thesis Sharif University of Technology ; Rajabi Ghahnavieh, Abbas (Supervisor) ; Fotuhi Firuzabad, Mahmud (Co-Advisor)
Abstract
Mass production of Plug-in Hybrid Electric Vehicle (PHEV) and requests for long trip capability necessisated development of fast charging station that can charge PHEV in a feuling time of a conventional vehicle. Fast charging station design requires a systematic approach to consider various related issues.
The aim of this thesis is to design a fast charging station. First, the daly demand for PHEV charging is modeled considering number and type of PHEV as well as level and pattern of daily driving of PHEV. Uncertainty in daily driving and in PHEV state of charge in the start of charging are also considered in modeling charging demand. An approach, then, is proposed for optimal design of...
The aim of this thesis is to design a fast charging station. First, the daly demand for PHEV charging is modeled considering number and type of PHEV as well as level and pattern of daily driving of PHEV. Uncertainty in daily driving and in PHEV state of charge in the start of charging are also considered in modeling charging demand. An approach, then, is proposed for optimal design of...