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In this paper some of the problems related to electrical drives in modern elevators are presented. These are the modeling of jerk and the definition of the motion trajectory, power savings, efficiency optimization and possibilities for energy storage in generator mode, and application of suitable converters and control techniques for the implementation in elevator drives. Suggested solutions are tested...
Energy is one of the sectors directly affecting the economic growth and forming a significant part of overall expenses in several industry branches, especially in manufacturing. The development of the energy sector requires significant investments which can only be attracted in a stable and predictable investment environment. Therefore, Latvian energy sector is being planned in a long-term both globally...
The process of globalization poses new challenges for the government in the field of education system regulation. The growing importance of the need for a qualitative assessment of the state of the educational process contributed to the development of one of the new scientific directions — the issue of quality management of higher education. Despite the fact that a lot of publications have appeared...
The purpose of this paper is to present the achievement of the Hybrid Petri Nets techniques used for modeling and behavioral analysis of a class of hybrid systems. In our sense, a dynamic hybrid system contains at least two distinct subsystems which interact: a continuous subsystem (linear, or not) and a discrete subsystem with a finite number of states. In this context, after a brief introduction...
Confront location based on camera tracking is an active research area as it offers numerous applications, particularly for security-based surveillance, robot vision and visual guidance. This paper presents a camera calibration technique for target tracking by designing a feedback control system for a camera mounted servo based gimballed eye structure which in turn signals the tracking station to position...
In this paper it is designed the automatic system for formation the small pieces from polymer, based on the principle of thermoplastic extrusion. The system has a goal to form pieces with a maximum volume of 20535 mm3. Arduino Mega 2560 and an extension of Ramps 1.4 were used as the control module, and the control of the stepper motors is done by the A4988 drivers. The mathematical model of the thermal...
It is reported an investigation of control action (CA) of the energy source in the automatic control system of thermal process' parameters in the technology of the epitaxial growing of the compound layers A3B5 by the reaction transport method in the quasi-rapidity conditions. These conditions superpose more rigid requirements of dynamic error over the minimum value of static error in the modern technological...
This work presents a robust control approach for Maximum Power Point Tracking (MPPT) of a standalone solar Photo Voltaic (PV) system, in order to boost its efficiency. For testing the algorithm, it was considered an 80W stand-alone solar PV cell. In order to improve the efficiency of the charge controller, the proposed control strategy follows the maximum power point output.
This paper presents a new method of simultaneous estimation of speed and rotor resistance of an induction motor, from a sensorless vector control system. The simultaneous estimation of the speed, rotor flux and of rotor resistance is done by using an adaptive estimator, called the COS observer. To ensure the persistent excitation condition, in the vector control system, over the rotor flux reference,...
In this paper sliding mode controller is designed in comparison with the linear state space feedback controllers namely the pole placement controller and linear quadratic regulator to eliminate the chaotic limit cycle oscillations in Van der Pol system induced by an external sinusoidal excitation in order to avoid failure in physical structures. The controller design is based on the mathematical model...
Annotation — This paper presents a synthesis method for delay time evaluation in the printed circuit boards based on Timed Hard Petri Nets. For the specification and modeling of the delay time evaluation system, Timed Synchronous Petri Nets (TSPN) are used. The transition to the hardware description of the system is achieved by translating the TSPN into Timed Hard Petri Net (THPN). The implementation...
This work presents the implementation of a control strategy for a hybrid electric vehicle (HEV) that uses a battery and an ultracapacitor as energy sources. For this configuration we developed a power demand prediction model which is intended for the power distribution of the vehicular system between the two sources. The proposed model, based on Wavelet decomposition and Neural Network, is a hybrid...
Functional Electrical Stimulation (FES) aims to induce programmed exercises in paralyzed limbs of people who suffered a stroke, in order to improve their rehabilitation process. Nowadays, surface pre-gelled transcutaneous electrodes are used to provide electrical pulses to the nerves which induce contractions to the targeted muscles. This paper presents a new type of electrodes which are embedded...
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