The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Flux-switching permanent magnet (FSPM) motor is a new brushless machine with magnets in the stator, offering the advantages of robust rotor structure, high power density and high efficiency. In this paper, a transient co-simulation method of coupled magnetic and electric circuit solvers is adopted for performance analysis of a FSPM motor drive. The magnetic circuit and the electric circuit are coupled...
This paper reports efficiency improvement of a doubly salient-pole homopolar machine with powder iron core. Powder iron core is composed of the metal magnetization powder with resin. It has advantages of low cost, isotropic magnetic property for three dimensions, a high flexibility of design, and low eddy-current loss at high frequency. This paper shows characteristics and performance comparisons...
Multi-consequent-pole bearingless motors can be used in low speed rotating and swinging stages (or platforms) under specific conditions. A test machine has been designed and built and in this machine two axes of freedom are actively controlled in the radial x-y directions. The suspension windings are of a novel toroidal shape, i.e., they are wound around the stator yoke. This produces a low axial...
In this paper, a novel structure for axial-flux generators in automotive applications is presented. The machine has a field winding in the inner part of the stator core around the rotor shaft. Because of unidirectional magnetic flux in the stator, the generator behaves as a homoploar machine. For better utilization of the generator, grain oriented silicon steel laminations are used for the stator...
In this paper, the time-delayed feedback control method is introduced to stabilize unstable equilibrium points undergoing Hopf bifurcation for an induction motor (IM) drive system. Stability criterion of a nonlinear time-delayed system is first established, and then an effective procedure is shown how to stabilize the unstable equilibrium points by suitably select the feedback gain k and the time-delay...
As the rotor temperature rise of line-start rare earth permanent magnet synchronous motor (REPMSM) is much higher than tradition expected theoretically during the synchronous operation, in order to analyze the reason in-depth, in this paper, the dynamic starting process of the line-start REPMSM in the load and no-load conditions was simulated by two-dimensional finite element method (FEM) using MagNet...
Renewable energy sources, especially wind turbine generators, are considered as important generation alternatives in electric power systems due to their no exhausted nature and benign environmental effects. Compared to conventional synchronous generator, permanent magnet synchronous generator has many outstanding performances. Due to the technical and economical advantages, low-speed permanent magnet...
A simple analytical method is developed to compare the combinations of stator and rotor pole numbers in flux-switching PM machines in terms of back-EMF and electromagnetic torque. The winding connections for machines having all poles and alternate poles wound are determined, based on the coil-EMF vectors. The conditions are established for balanced symmetrical back-EMF waveform. It shows that the...
To study the performance of line start permanent magnet motors, this paper investigates two typical rotor designs which have different magnet arrangements, including the interior-magnet rotor and the surface-magnet rotor. The transient and steady states of these motors are calculated by using two-dimensional finite-element analysis. Characteristics such as flux distribution, efficiency, and loading...
This paper presents a new method of on-line estimation for the stator and rotor resistances of the induction motor in the indirect vector controlled drive, using artificial neural networks. The back propagation algorithm is used for training of the neural networks. The error between the rotor flux linkages based on a neural network model and a voltage model is back propagated to adjust the weights...
With the purpose of improving the operation efficiency of wind power generator, this paper, by analyzing the doubly-fed induction generatorpsilas (DFIG) power characteristic, built up the DFIG active power reference calculation model to achieve the maximal power point tracing (MPPT) and the reactive power reference calculation model to minimize generator loss. The stator flux-linkage oriented vector...
This paper presents a decoupling method for speed-sensorless vector control of induction motor to track the flux command fast and eliminate torque ripples in flux-varying environment, such as field-weakening operation and efficiency optimization. Rotor flux-oriented control can decouple the speed and flux control. However, the decoupling is on the condition of a constant rotor flux. When motor drives...
This paper presents an improved speed sensorless vector control method for general-purpose induction motors (IMs). The proposed method is based on the d-q axis dynamic model of the induction motor and an improved closed-loop flux observer, which can achieve precise rotor and stator flux estimation over a wide speed range. And then, a rotor-speed-estimation method, based on fuzzy control theory, is...
A novel control method for Permanent Magnet Synchronous Motor (PMSM) position servo systems is presented, which can greatly improve the dynamic performance of servo systems. In this method, the maximum reaching velocity control is introduced to reconstruct the conventional three closed-loop PID regulators. Under the new velocity and position control modes (two-segment modes), the PMSM servo systems...
In this paper, a method is presented and achieved to accurately determine Hopf bifurcation point for an induction motor (IM) drive system, and Hopf bifurcation diagram is showed to indicate evolvement of the equilibrium points from steady state to undergoing Hopf bifurcation and then achieving stabilization again. At last, the classical Floquet theory is applied to confirm the limit cyclepsilas stability.
Two magnetic fields produce radial force on rotor when the difference of their pole pair numbers is 1. Based on this principle, this paper introduces the bearingless motor with a single set of 5-phase windings. The MMF waveform produced by multiphase windings is analyzed, based on which the winding configuration of 5-phase bearingless motor is introduced. The two needed magnetic fields are produced...
This paper emphasizes to develop a hybrid detection scheme for broken rotor bar fault in induction motors. Since the power spectrum density estimation of classical multiple signal classification (MUSIC) possesses higher resolution with short-time samples compared with FFT, this paper applies MUSIC to detect broken rotor bar fault. And thus, the impacts of the fluctuation of stator current can be decreased...
The broken rotor bar is one of the frequent faults in squirrel cage induction motors. Fault detection based on a common steady-state analysis technique, such as FFT, is significantly dependent on the loading conditions of induction motors. At light load, it is difficult to distinguish between healthy and faulty rotors. This paper provides two detection methods based on digital signal processing system...
The electromagnetic characteristic and rotor vibration characteristic of turbine-generator are analyzed when rotor winding inter-turn short circuit fault has happened. This paper reveals that exciting magnetic force Ff is constant in a fixed condition whereas the exciting current If increases in case of rotor inter-turn fault. This paper also finds relevant characteristic parameters. Based on the...
A new fault diagnosis method of inter-turn short circuit detection in generator rotor windings based on wavelet transform is presented. The detection method is based on the singularity characteristics of the induced electromotive force signal of search coil in the air gap. Electromagnetism characteristic of turbo-generator rotor windings is analyzed. Wavelet transform was applied to the detection...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.