Search results for "Motor"

Flux density at the airgap of small DC motors with different permanent-magnet poles

1993

A stepper motor-driven microelectrode positioner

1987

The mechanical elements and the electronic control system from a stepper motor-driven microelectrode positioner is described. The unit embodies a high-precision small step angle hybrid motor. The compact, rugged and totally concentric design of the mechanic, by a spindle mechanism achieves the necessary precision by translating the stepwise rotations of the motor into steps of linear movement. The system takes advantage of commercially available low friction parts such as ball bearings, ball bushings and axles with hardened surfaces. The related electronic control unit is designed around the most recent integrated circuitry which is both sophisticated and economical. Though the described sy…

Sensorless variable speed single-phase induction motor drive system based on direct rotor flux orientation

2012

The single-phase induction motor (SPIM) is one of the electrical machines more used in the World, and can be found in several fractional and sub-fractional horsepower applications in houses, offices, shoppings, farms, and industries. The introduction of more sophisticated applications has required the use of variable speed drives for SPIM, where the adoption of sensorless techniques is the more reasonable option for speed control due to the low cost of this electrical machine. A proposal for sensorless variable speed SPIM drive based on direct rotor field orientation techniques is presented in this paper. None transformation is used in order to eliminate the asymmetry of the stator windings…

Robust Active Disturbance Rejection Control of Induction Motor Systems Based on Additional Sliding-Mode Component

2017

This paper deals with motion control systems with induction motor, subject to severe requirements on both dynamics and steady-state behavior. The proposed control methodology could be viewed as an advancement of the standard field oriented control. It consists of two control loops, i.e., the rotor flux and the speed control loops, designed using the active disturbance rejection control method, with the aim to cope with both exogenous and endogenous disturbances, which are estimated by means of two linear extended state observers and then compensated. Moreover, with the aim of achieving total robustness, a sliding-mode based component is designed, in order to take into account disturbance es…

Sensorless variable speed single-phase induction motor drive system

2012

It is usual find single-phase induction motor (SPIM) in several house, office, shopping, farm, and industry applications, which are become each time more sophisticated and requiring variable speed drives. Considering the low cost of this machine, the adoption of sensorless speed control is the more reasonable option for SPIM drives. This paper presents a proposal for sensorless variable speed SPIM drive based on direct rotor field orientation techniques. An observer based on two independent linear close-loop control systems provides the estimation of the rotor flux and speed from the measurements of the stator currents and voltages. These estimatives are used by close-loop systems for speed…

Speed control of tubular linear induction motors for industrial automated applications

2016

The Tubular Linear Induction Machine (TLIM) has acquired great relevance over the past years for industrial automated applications. For this purpose, the complete modeling, simulation and determination of the parameters of a TLIM is presented in this paper. In addition, the TLIM speed control for this specific application is here described. In order to verify the performances of the proposed system, a test bench has been setup and good agreement is shown from the comparison between measured and simulated results.

Eccitabilità corticale e ciclo emicranico: studio condotto con stimolazione magnetica transcranica in pazienti affetti da emicrania con e senza aura …

Emozioni in movimento

2013

The function of olfactory experience in reasoning : An empirical study

2019

This study reports the role of olfactory experience (i. e. smell of medication) in a nine-year old girl’s reasoning in pair-work situation where the children were asked to choose items useful on a desert island. The extract analysed here is part of the larger data set of my dissertation, in which I investigate how sensory-motor activities involved in reasoning. I video-recorded an experimental task, in which the participants (N=27; age=9; Hungarian L1) have been asked to choose 7 items out of 14 to take those to an imaginary uninhabited island. The multimodal analysis shows that children did not choose the vitamin pills due to its unpleasant smell. The findings suggests that crossmodal expe…

Development of need for recovery from work over one year: A person-centered approach

2011

This longitudinal questionnaire study conducted among 274 Finnish employees (57% women, average age 45.9 years) in a variety of jobs aimed at identifying groups of employees who share similar mean levels and changes in need for recovery and finding out whether factors regarded as antecedents of need for recovery distinguish between the different groups of need for recovery across one year. Using mixture modeling eight groups of need for recovery were identified. The individuals identified as closely resembling each other with respect to need for recovery and its change across one year were considered to belong to the same need for recovery group. Five of these groups indicated stable (low, …