Search results for "Power Loss"
showing 10 items of 25 documents
Predictive dead time controller for GaN-based boost converters
2017
A dynamic dead time controller is presented, specifically intended to operate in synchronous boost converters based on GaN field-effect transistor switches. These transistors have a reduced stored charge with respect to silicon metal–oxide–semiconductor field-effect transistors with similar breakdown voltage and series resistance, and can operate at higher frequencies with reduced switching losses. On the other hand, the voltage drop in reverse conduction is typically more than doubled with respect to silicon devices resulting in relevant power losses during the free-wheeling phases. Therefore, dynamic control of dead time can be profitably applied even in converters operating in the tens o…
Uncertainty evaluation in the differential measurements of power losses in a power drive system
2021
Abstract In order to guarantee a correct classification in the standardized energy efficiency classes, the current standards concerning the power drive systems prescribe that their power losses must be evaluated with great accuracy. This circumstance involves the usage of expensive measurement systems, since accurate instrumentation, skilled personnel and controlled environments are required. During the design stage of a power drive system, however, the measurement of the absolute value of its power losses is not always needed. Often, in fact, it is enough to assess the power losses variations caused by a modification of either hardware or software sections of the power drive system. In the…
ICT applications for improving the generation and distribution efficiency of a small mediterranean island
2016
The paper presents a study on the opportunities offered by ICT for improving the efficiency of the generation and distribution system of a small island. The island taken into consideration is the Italian Lampedusa island. In the paper, the power distribution system of the island is described and the summer and winter daily load profiles are examined in order to define the more suitable control actions for improving the generation and distribution efficiency of the power system. Finally the architecture of an idoneous control system for the smart grid is proposed and an evaluation of the purchase and installation costs of components and devices for the transition of a traditional house towar…
Technical and economical comparison between different topologies of PV plant under mismatch effect
2014
This paper presents a technical and economical comparative analysis between two topology of photovoltaic plant. In particular the performances of series-parallel (SP) and total cross tied (TCT), topologies are taken into account, referring to a partially shaded photovoltaic plant. Thanks to a simulation model developed, in the paper the mismatch effects due to three different shading conditions, for SP and TCT topology plant, are quantified. Since the TCT solution, even though increase the energy production, raise the complexity of plants as well as their costs, an evaluation of the individual costs of each component of a SP and TCT plant topology, as PV modules, support structure, inverter…
Simple and Flexible Power Loss Minimizer With Low-Cost MCU Implementation for High-Efficiency Three-Phase Induction Motor Drives
2021
This paper presents a simple, practical and low-cost implementation of a power losses minimization algorithm for three-phase induction motors taking also into account both iron core losses and magnetic saturation. The algorithm evaluates, in real-time, the optimal direct axis magnetizing flux component for efficiency enhancement of the drive. A further advantage of the proposed technique is represented by a flexible and low-cost implementation by means of an ATMEL ATSAM3X8E microcontroller. The power loss minimization algorithm is tested preliminarily by means of several simulations, then, experimentally validated by applying the proposed control strategy on a 5.5 kW Field Oriented Control …
Effects of short inter-repetition rest periods on power output losses during the half squat exercise
2016
BACKGROUND: Cluster training is being increasingly used to develop muscular power. OBJECTIVE: To determine the effects of short inter-repetition rest (IRR) periods on the capacity to maintain maximal levels of power output. METHODS:In afirst session, 16 active-duty soldiers performed a progressive loading test toestablish the load linked tomaximal power (optimal load, OL), and the half squat 1-repetition maximum. In Session 2, six individual sets of repetitions performed to failure (or a maximum of 20 repetitions) were conducted using the loads OL, low (LL, 15% below OL), and high (HL, 15% above OL) as quickly as possible. For each load, participants performed one set without rest between r…
An accurate measurement procedure of power losses variations in electrical drives
2020
This paper presents a general procedure for the accurate measurement of power losses variations in electrical drives. More specifically, the paper addresses the issue related to the efficiency comparison of electrical drive controlled with different control algorithms. This procedure is applied to a permanent magnet synchronous motor drive, assessing its power losses by means of two different measurement systems, each one characterized by different accuracy and cost. The comparison between these two systems is carried out for different working conditions in terms of load, speed and magnetization in order to demonstrate that the power losses variations can be accurately measured even with no…
Efficiency Improvement of Inverter-Fed Permanent Magnet Synchronous Motors
2003
In this paper a control algorithm for the efficiency improvement of inverter-fed permanent magnet synchronous motors (PMSMs) is presented. The proposed algorithm allows reducing the losses of the drive without reduction of its dynamic performances. In details, after recalling a dynamic model of the PMSM, which has been purposely modified and that takes into account the iron losses, the basic equations and the constraints to obtain the loss minimization are presented and discussed. Some simulations of a specific PMSM drive employing the proposed algorithm are performed. The results of these simulations show that the dynamic performances are maintained, and enhancement of the efficiency up to…
Characterization of interior permanent magnet synchronous motors for loss model algorithm identification
2016
The paper provides the results of a detailed experimental study on the variations of the characteristics of an interior permanent magnet synchronous motor, when load, speed and/or magnetization conditions vary. In particular, the characterization is carried out by assessing, for several working conditions, the motor parameters that influence its efficiency. From the knowledge of the variability of these parameters, it is possible to develop a dynamic model of the motor, which accurately describes its behaviour and allows estimating the power losses for whatever speed and load. In order to validate the model, the values of the power losses obtained by using the model are compared with the va…
Comparison of three control drive systems for interior permanent magnet synchronous motors
2017
In a previous paper, we proposed a control strategy for interior permanent synchronous motors, which takes into account also the reduction of the motor power losses. The novelty of the suggested approach is that it takes into consideration the variations of all the motor parameters that have an influence on its efficiency. In order to verifyon the field the effectiveness of this new method, we implemented the proposed loss model algorithm in a control drive system and compared its performances, in terms of energy losses with respect to other conventional techniques.