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In many applications, industry has tried to develop sinusoidal supply for brushless DC (BLDC) motors. This paper describes a method that still keeps a simple 2 phases-on sensorless method and achieves sinusoidal supply, which is needed to avoid speed oscil ...
To be able to calculate the performances of a hybrid stepping motor or to design it in a short time, it is essential to apply an efficient model, accepting a slight loss of precision. Using software based on finite elements and executing calculations are d ...
In this paper, a method for sensorless position estimation of linear transducers at standstill is suggested. The method makes use of current pulses, which is a common sensorless starting technique for 3-phase synchronous motors. Most transducers possess ho ...
We will present a method allowing to evaluate the mechanical performances (torque, speed, mechanical power, dissipated losses in the surface of contact between stator and rotor) of the travelling wave ultrasonic motors. The visualization of the motor chara ...
Usually, each phase of the direct reluctance motor is fed separately by its own inverter producing a squarewave phase current depending on the rotor position. In the present work, a star-connection of the three stator phases is used and the direct reluctan ...
NOVELTY - After disconnection from normal control (3) a pulse generator (4) sends positive and negative pulses to a motor winding R. The response currents are measured (5) from voltages (Vpr,Vnr) which appear after a fixed time on a neutral resistor (2) an ...
The brushless DC motors are normally built with rotor mounted PMs, which create the necessary back EMF voltage to produce a mechanical power. The shape of this back-EMF voltage is very important compared to the phase voltage supply one. Indeed, the electro ...
In some applications, contacts between two devices are the first cause of dysfunctions. The aim of this study is to transfer contactless power energy to add new functions to a tool (drill machine for example). A bi-directional communication is also needed. ...
The paper deals with the determination of synchronous machine parameters using a 2D Finite Element Method – FEM (Flux2D- Cedrat). Simulations of no-load sudden three phase short- circuits are performed in rotation, the saturation effects and the eddy curre ...
With brushless DC Motor (BLDC), current regulators in dq axes are very appreciated for sinusoidal supply. As the set current is constant, the regulator works properly. When the back-EMF is not sinusoidal, current oscillations appear in the dq regulator. A ...
