Search results for "Motor"
showing 10 items of 3137 documents
Enhanced flexible algorithm for the optimization of slot filling factors in electrical machines †
2020
The continuous development in the field of industrial automation and electric mobility has led to the need for more efficient electrical machines with a high power density. The improvement of electrical machines’ slot filling factors is one of the measures to satisfy these requirements. In recent years, this topic has aroused greater interest in the industrial sector, since the evolution of the winding technological manufacturing processes allows an economically sustainable realization of ordered winding arrangements, rather than random ones. Moreover, the manufacture of electrical machines’ windings must be preceded by an accurate design phase in which it is possible to evaluate the maximu…
Downsizing the Electric Motors of Energy-Efficient Self-Contained Electro-Hydraulic Systems by Using Hybrid Technologies
2020
Abstract The ongoing tendency toward the electrification of hydraulic systems, mainly in the form of self-contained solutions, poses design challenges in high-power applications. An electric motor drives positive-displacement machines used to control the motion of the hydraulic actuator (nonhybrid systems encompassing one or two pumps exist in the technical literature). All the power managed by the actuator passes through the electric motor, which leads to often oversized arrangements. These detrimental characteristics are especially pronounced when the power level increases approximately above 35–40 kW. Therefore, this research paper presents and studies a self-contained, electro-hydraulic…
Energy management strategy to reduce pollutant emissions during the catalyst light-off of parallel hybrid vehicles
2020
Abstract The transportation sector is a major contributor to both air pollution and greenhouse gas emissions. Hybrid electric vehicles can reduce fuel consumption and CO2 emissions by optimizing the energy management of the powertrain. The purpose of this study is to examine the trade-off between regulated pollutant emissions and hybrid powertrain efficiency. The thermal dynamics of the three-way catalyst are taken into account in order to optimize the light-off. Experimental campaigns are conducted on a spark-ignition engine to introduce simplified models for emissions, exhaust gas temperature, catalyst heat transfers and efficiency. These models are used to determine the optimal distribut…
Bearing fault diagnosis for inverter-fed motors via resonant filters
2014
Current-based technique is an economic solution to detect bearing faults in drive-trains. Localized faults produce characteristic vibration frequencies. When an electric motor is supplied by a frequency-converter, the current response includes not only the fundamental and fault related frequencies but also higher harmonics from the inverter. This paper introduces a resonant filter to pick up frequency components caused by the localized faults. The bearing fault frequencies are calculated by bearing geometry and motor speeds. The filter frequencies are selected as a function of motor speeds. The filter is independent of the load condition, so it can work at different motor operating points t…
Experimental comparison between direct and indirect measurement techniques for the characterization of Linear Induction Motors
1997
Abstract An experimental comparison between direct and indirect measurement techniques for the on-line characterization of Linear Induction Motors (LIMs) is presented. Indirect measurements are based on a mathematical model of the motors. Direct measurements are carried out by means of traditional instruments and a smart sensor, located on the LIM and linked to the controller by the power supply line. Both a synthetic description of the LIM model and the sensor architecture are reported. The experimental results, achieved by applying different feeding strategy, are discussed.
A Contribution to Tests Standardization for Inverter-Fed Asynchronous Machines
1986
Losses of inverter-fed asynchronous motors and their experimental evaluation are considered. The formal expressions of iron and copper losses are first recalled, and it is shown as they are influenced by the harmonic content of inverter output voltages. Theoretical and experimental values of these losses are then given together with the presentation of the experimental tests used for their determination. A suitable set of tests is then suggested for the determination of the conventional efficiency of inverter-fed asynchronous motors. The content cannot be considered exhaustive on the matter. It represents only a first contributive approach to the standardization of inverter-fed asynchronous…
Remote diagnosis and control of wheelchair electrical drive systems
2005
A new Diagnostic and Protective System (DPS) suitable for wheelchair electrical drive applications has been prepared. Such a system is able to perform both monitoring and long-distance transmission of key signals that are used as pre-fault and fault indicators. The system, moreover, may detect several anomalous working conditions by means of reliable diagnosis procedures and carries out actions to protect the electrical drive and to drive the disabled people in safe conditions. In particular the design, the realization and the performance analysis of the new dedicated diagnostic system, which exploits a programmable logic controller (PLC) as DRS hardware, are described and discussed. The ef…
Improving the Efficiency and Dynamic Properties of a Flow Control Unit in a Self-Locking Compact Electro-Hydraulic Cylinder Drive
2019
Abstract The introduction of low cost electric motor and drive solutions provides the possibility to design cost competitive compact speed-variable drives as potentially feasible alternatives to conventional valve-controlled solutions. A main drawback in existing self-contained drive technology is the power consumption in stationary load carrying situations. However, the recent introduction of compact self-locking drive topologies with separate forward and return flow lines allow to significantly minimize the power consumption, but introduces another problem. Dependent on the control of the flow device, a continuous, but lower power consumption compared to non-self-locking drive topologies …
CNN based Gearbox Fault Diagnosis and Interpretation of Learning Features
2021
Machine learning based fault diagnosis schemes have been intensively proposed to deal with faults diagnosis of rotating machineries such as gearboxes, bearings, and electric motors. However, most of the machine learning algorithms used in fault diagnosis are pattern recognition tools, which can classify given data into two or more classes. The underlined physical phenomena in fault diagnosis are not directly interpretable in machine learning schemes, thus it is usually called black/gray box models. In this study, convolutional neural networks (CNN) machine learning algorithm is proposed to classify gearbox faults, and the learning features of the CNN filters are visualized to understand the…
A model of a linear synchronous motor based on distribution theory
2012
The fundamental idea of this paper is to use the distribution theory to analyze linear machines in order to include in the mathematical model both ideal and non ideal features. This paper shows how distribution theory can be used to establish a mathematical model able to describe both the ordinary working condition of a Linear Synchronous Motor (LSM) as well the role of the unavoidable irregularities and non ideal features.