back emf

The force constant and its associated back- EMF constant of a VCM can be highly nonlinear with the mechanical structure.

However, the torque ripple at the 79% pole-arc to pole-pitch ratio is not minimal although the THD of back EMF is minimal at this point.

However, it is possible to achieve the sinusoidal back EMF waveform at the small pole-arc to pole-pitch ratio.

Table II shows the total harmonic distortion (THD) of each phase back EMF.

After that, a rotor position estimator is proposed. By detecting the back emf, a rotor position of the motor can be obtained.

Therefore, the back EMF owing to pole-arc to pole-pitch ratio is analyzed prior to the decision of magnetic loading.

The A8904 provides complete, reliable, self-contained back-EMF sensing, motor startup and running algorithms.

Therefore, we can verify that the THD of back EMF is not always related to the torque ripple in the IPMSM.

The mechanical platform of unregulated voltages, power and back-EMF spikes, and the electronic platform of clean power and 5-volt signals.

Fig. 3 shows the comparison results of phase back EMF between the simulation and the experiment.

What the G9SX-SM does differently is to monitor the back-EMF from the motors directly producing the motion in the hazardous area.

In this paper, a method of back-EMF logic commutation for brushless DC motor is presented.

Animproved sensing back-EMF method of sensorless BLDC motor was proposed by analyzing typical back-EMF zero-crossing detecting method.

In order to minimize torque ripple, the waveform of phase back EMF should be sinusoidal at no load operation.

The THD of back EMF is minimized at the 79% pole-arc to pole-pitch ratio.

Using Back-EMF method to control BLDCM, it can realize sensor-free control method by detecting the zero point of EMF in this paper.

On the other hand, when the motor is operated in middle to high speed range, the stator current is continuous. The back emf can be computed.

Calculation of Air Gap Magnetic Flux Density and Back EMF Waveform in Permanent Magnet Brushless DC Motor

Analysis of Back-EMF in Permanent-Magnet Brushless DC Motor with Concentrated Winding

The Starting Method's of the BLDC Motor Using Back EMF to Monitor the Rotor Position

Discussion about the method of back-EMF commutation for brushless DC motor

Study on Method of Direct Back EMF Detection for Position Sensorless Brushless DC Motor

Based on Back-EMF Estimation Discrete Time Direct Torque Control of Induction Machines

Research on Closed-Loop Control of Hybrid Step Motor Using the Harmonic Back EMF

Study of Brushless DC Motor Based on Back-EMF Method

Analysis of Best Commutation Logic in Control of Brushless DC Motor Based on Back-EMF Method

New Logic Commutation Method Based on Back EMF for Brushless DC Motor

Sensorless Brushless DC Motor Based on Detecting Harmonic Signals of Back-emf