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Developing a research autonomous plane for flying in a laboratory space is a challenge that forces one to understand the specific aerodynamic, power and construction constraints. In order to obtain a very slow flight while maintaining a high maneuverabilit ...
The number of brushless DC (BLDC) motor applications has increased significantly, essentially due to reduced costs of semiconductors and permanent magnets, but also because of the emergence of new control strategies, such as closed-loop and sensorless cont ...
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 ...
This paper describes a low cost sensorless position detection scheme for a brushless DC motor. This method is based on interruption of the 3 phase-currents and reading the back-EMF. The hardware for measuring the back-EMF is very simple. The method is poss ...
In some applications, it is interesting to know the position of a BLDC Motor at standstill. This paper propose one solution using the saturation property of the motor. Principle, simulation and measures are presented. The results of industrial applications ...
The Industrial Electronics Laboratory at the Swiss Federal Institute of Technology (EPFL) in Lausanne has built a prototype of a revolutionary two-wheeled vehicle. Due to its configuration with two coaxial wheels, each of which is coupled to a DC Motor, th ...
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 ...
When we achiev a good performance of the field-oriented vector control system, it is necessary to detect the speed and flux of the motor. Usually it is hard to implemment these sensors. Then the sensor-less contro-system techniques using the observer inste ...
The photogoniometer is composed of a computer-controlled movable mechanical support, presenting two main rotation axes that are powered by DC motors. It uses an accurate and reliable gear technology (harmonic drivers) and is controlled by a micro-computer. ...
Poling of lead zirconate titanate pyroelectric thin films has been studied. Poling temperature and electrical field were optimized to achieve high figures of merit. We have found a direct correlation between the onset of degradation current and the final p ...