Search results for "mot"
showing 10 items of 16577 documents
Experimental Investigation of Efficiency Map for an Inverter-Fed Surface-Mount Permanent Magnet Synchronous Motor
2019
Losses in inverter-fed permanent magnet motors are underestimated by using analytical or numerical approach since additional losses due to extra harmonics of the frequency converter are normally skipped. Further, losses in switches and passive components of the converter and the effect of switching frequencies cannot be numerically taken into consideration. Loss-minimizing control and proper efficiency analysis of inverter-fed permanent magnet motors cannot be achieved if an efficiency map is built based on a numerical investigation of the motors alone. This works first reviews losses in a surface-mount permanent magnet synchronous motor (SPMSM) and frequency converters. The efficiency map …
On the mechanics of magnetic fluids with field-induced phase transition: application to Couette flow
2018
The influence of Brownian diffusion and magnetophoresis, which are followed by phase transition, on the characteristics of a stationary plane Couette flow of magnetic fluid in a non-uniform magnetic field is discussed. The phase transition conditions in magnetic fluids are assumed as a natural restriction to the particle concentration increase in a non-uniform magnetic field. Profiles of the particles' concentration are calculated, and dependences of the volume magnetic force and of the viscous force are established. © 2018 Institute of Physics, University of Latvia.
A Planar Generator for a Wave Energy Converter
2019
This article presents a permanent magnet planar translational generator which is able to exploit multiple modes of sea wave energy extraction. Linear electrical generators have recently been studied for the exploitation of sea wave energy, but, to the best of our knowledge, no synchronous planar translational generator has been proposed. In this article, to maximize the energy extraction, we have considered all the potential modes of motion due to wave excitation and included them within the mathematical model of the proposed system. The principle of operation of the generator can be summarized as follows: the moving part (translator) of the generator is driven from the sea waves and induce…
Identification of parameters and harmonic losses of a deep-bar induction motor
2017
High frequency harmonics from a frequency converter causes additional losses in a deep-bar induction motor. The harmonics have their own amplitude and phase with respect to the fundamental signal, but the harmonic loss is only dependent on the amplitude of harmonics. A deep-bar induction motor can be modelled by a triple-cage circuit to take skin effect into account. The triple cage circuit having many parameters could be estimated from a small-signal model of the machine by using Differential Evolution. The correctly estimated parameters make the triple-cage circuit valid in a wide range of frequencies. However, the triple-cage circuit is very complicated which makes it difficult to model …
Control flow strategy in a receiver coil for nuclear magnetic resonance for imaging
2020
A mathematical discussion is introduced to describe the receiver coil characterizing a nuclear magnetic resonance for imaging, starting from a general shape of the conductor. A set of different inductance calculations have been introduced, varying the shape of the conductor. The inductance calculation led to a general expression of the magnetic field of a single coil characterized by a rectangular shape. A dynamic model of the receiver coil has been developed to represent the natural frequencies that characterize the operational bandwidth. A nonstationary control strategy is implemented to make a real time changing of the operational bandwidth. The frequency response of the coil generates …
Experimental comparison of two control algorithms for low-saliency ratio interior permanent magnet synchronous motors
2018
In this paper, an experimental investigation on the comparison between the Maximum Torque Per Ampere (MTPA) and the Field Orientation Control (FOC) algorithms for interior permanent magnet synchronous machines (IPMSMs) is described, analyzed and discussed. This investigation was carried out on a small-power IPMSM with low saliency ratio. More in detail, after a previous simulation study, the control techniques have been experimentally implemented and validated through means of a dSPACE® rapid prototyping system. The performances of the two algorithms have been evaluated and compared, obtaining interesting results.
Enhanced loss model algorithm for interior permanent magnet synchronous machines
2017
This paper presents an experimental study on the impact of the parameter variations over the performances of a LMA (Loss Model Algorithm) designed for an IPMSM (Interior Permanent Magnet Synchronous Machine). In a previous work, the characterization was carried out by assessing, for several working conditions, the motor parameters that influence the motor efficiency. The proposed enhanced loss model algorithm is implemented in a rapid prototyping system and its performances, in term of efficiency, are compared with other control systems, obtaining promising results.
Parameter sensitivity of flux-linkage based sensorless control for permanent magnet synchronous motors
2017
Sensorless control can be utilized to reduce cost, size and total complexity of a motor drive or enhance reliability of the system. This paper first presents a sensorless control algorithm for a surface permanent-magnet synchronous motor (SPMSM) based on estimated flux linkages and stator currents. Within the algorithm, rotor position error can be predicted by comparing the estimated currents with measured stator currents. Performance of the sensorless control based on flux-linkages and the dependency of the algorithm on motor parameters is then numerically investigated via simulations. It is found from the investigation that the accuracy of the method depends on the motor working condition…
Data-driven Fault Diagnosis of Induction Motors Using a Stacked Autoencoder Network
2019
Current signatures from an induction motor are normally used to detect anomalies in the condition of the motor based on signal processing techniques. However, false alarms might occur if using signal processing analysis alone since missing frequencies associated with faults in spectral analyses does not guarantee that a motor is fully healthy. To enhance fault diagnosis performance, this paper proposes a machinelearning based method using in-built motor currents to detect common faults in induction motors, namely inter-turn stator winding-, bearing- and broken rotor bar faults. This approach utilizes single-phase current data, being pre-processed using Welch’s method for spectral density es…
Space‐vector state dynamic model of SynRM considering self‐ and cross‐saturation and related parameter identification
2020
This study proposes a state formulation of the space-vector dynamic model of the Synchronous Reluctance Motor (SynRM) considering both saturation and cross-saturation effects. The proposed model adopts the stator currents as state variables and has been theoretically developed in both the rotor and stator reference frames. The proposed magnetic model is based on a flux versus current approach and relies on the knowledge of 11 parameters. Starting from the definition of a suitable co-energy variation function, new flux versus current functions have been initially developed, based on the hyperbolic functions and, consequently, the static and dynamic inductance versus current functions have be…