Search results for "efficiency [trigger]"
showing 10 items of 27 documents
Experimental investigation on high efficiency real-time control algorithms for IPMSMs
2014
This paper describes an experimental investigation on the power losses variations occurring in an Interior Permanent Magnet Synchronous Motor (IPMSM) with respect to the direct axis current component. Such investigation can be useful to determine a mathematical model accounting for copper, iron and mechanical friction losses, and for the arrangement of a speed control drive system equipped with a real-time power losses minimization algorithm. In particular, a test bench has been set up in order to carry out all measurements and the final power loss identification. The test bed is composed by a IPMSM drive with a field oriented control (FOC) strategy, a power analyzer, a dynamometric brake a…
An induction motor speed measurement method based on current harmonic analysis with the Chirp-Z Transform
2005
This paper presents a new method to measure motor speed by means of frequency estimation of rotor slot spectral components in the supply current of squirrel single-cage induction motors. The novelty of the method consists in the harmonic analysis of the supply current by means of the chirp-Z transform (CZT). The advantages are improved accuracy due to better spectral resolution and resolvability. Moreover, a shorter observation window is required, thus reducing errors related to nonstationary current signals. The experimental results are presented to validate the proposed method and to make a comparison with a similar method based on the fast Fourier transform (FFT).
Smart Cities and Municipal Building Regulation for Energy Efficiency
2015
The “Smart Cities & Communities Initiative” of the Strategic Energy Technology Plan is the strategic European response to lead cities and regions to a carbon free future. In this contest energy efficiency in buildings has a crucial role and must be considered in a holistic approach to the urban planning. In order to implement the minimum requirements stated by the European Directive about the Energy Performance of Buildings, and in order to consider different planning layers with the view to a smart city planning, local regulations are a key factor aiming at sustainable territorial planning. This paper investigates the possibility to draft a basic structure of Municipal Building Regulat…
Interior permanent magnet synchronous motors: Impact of the variability of the parameters on their efficiency
2016
In the scientific literature, various authors presented different control strategies aimed to increase the efficiency of the interior permanent magnet synchronous motors. These strategies, starting from a well-known mathematical model of the dynamic behaviour of the motor, are able to reduce the power losses acting on the magnetizing component of the stator current. However, none of the proposed approaches takes into account that, varying the working conditions of the motor, also the values of the parameters, which have an impact on the power losses, can vary. In this paper, therefore, starting from an accurate measurement of the motor characteristics for various values of speed and load, w…
Experimental study on efficiency enhancement in Interior Permanent Magnet Synchronous machines
2015
This paper presents an experimental study on the efficiency variation occurring in an IPMSM (Interior Permanent Magnet Synchronous Motor) with respect to the direct axis current component and for several working conditions. Such investigation is the starting point for the arrangement of a speed control drive system equipped with a real-time power losses minimization algorithm. More in detail, a test bench is set up to carry out the measurements needed for the final power loss identification. The experimental investigation is developed by performing tests at different speed, magnetization and load conditions. From the obtained results, it can be stated that the IPMSM efficiency can be maximi…
A simple method for the photometric characterization of organic light-emitting diodes
2022
A simple method for the photometric characterization of organic light-emitting diodes (OLEDs) is reported. It is based on the indirect measurement of the total emitted optical power by using a calibrated photodiode and the optical emission spectrum and space emission diagram of the OLED. From this and by measuring the current–voltage characteristic of the OLED all the relevant radiometric and photometric quantities can be extracted, including the external quantum efficiency. The usual method to collect all photons emitted by a LED source in the half space uses an integrating sphere with the LED source placed at the entrance hole and a photodiode (PD) placed at an exit hole at some point on …
Formulation, process conditions, and biological evaluation of dairy mixed gels containing fava bean and milk proteins: Effect on protein retention in…
2019
International audience; Food formulation and process conditions can indirectly influence AA digestibility and bioavailability. Here we investigated the effects of formulation and process conditions used in the manufacture of novel blended dairy gels (called "mixed gels" here) containing fava bean (Vicia faba) globular proteins on both protein composition and metabolism when given to young rats. Three mixed dairy gels containing casein micelles and fava bean proteins were produced either by chemical acidification (A) with glucono-δ-lactone (GDL) or by lactic acid fermentation. Fermented gels containing casein and fava bean proteins were produced without (F) or with (FW) whey proteins. The AA…
Equilibrium mergers in a composite good industry with efficiencies
2014
This paper studies equilibrium merging behavior in composite good industries. Component producers face the option to either merge with a similar component producer (horizontal merger) or a complementary one (complementary merger) of a composite good. Focusing only on strategic reasons, complementary mergers arise at equilibrium only when composite goods are very differentiated while horizontal mergers otherwise. Next, when efficiencies are considered, the level of marginal cost saving required for a horizontal merger in a composite industry to result in a non- increase in the upward price pressure index (UPPI) is greater as compared with the one in a regular industry. This result can be use…
DEA-like Models for the Efficiency Evaluation of Hierarchically Structured Units
2004
Abstract The knowledge of the internal structure of decision making units (DMUs) gives further insights with respect to the “black box” perspective when considering data envelopment analysis models. We present one-level and two-level hierarchical structures of the DMUs under evaluation. Each unit is composed of consecutive stages of parallel subunits all with constant returns to scale. In particular, the maximization of the relative efficiency of a DMU is studied. For the two-stage situation, different degrees of coordination among the subunits of the hierarchical levels are discussed. When some form of coordination has to be guaranteed, we introduce balancing constraints and we compare two…
An Exploratory Research of 18 Years on the Economic Burden of Diabetes for the Romanian National Health Insurance System
2020
The prevalence of diabetes mellitus (DM) rises constantly each year worldwide. Because of that, the funds allocated for the DM treatment have increased over time. Regarding the number of DM cases, Romania is among the top ten countries in Europe. Based on the National Diabetes Programme (NDP), antidiabetic drugs and other expenditures (Self-monitoring blood glucose (SMBG) test, HbA1c, insulin pumps/insulin pumps supplies) are free of charge. This programme has undergone many changes in drugs supply, in the last two decades: re-organizing the NDP, authorization of new molecules with high prices (e.g., SGLT-2 inhibitors, etc.) or new devices (e.g., insulin pumps, etc.) The main purpose of thi…