Monthly Archives: April 2019

Motor Run & Motor Start Capacitors

Electric motors exploit the interaction between two magnetic fields for rotating a shaft. The stator windings generate one of the fields, and the rotor windings provide the other. In some DC motors, permanent magnets replace one of the windings, while the commutator, whether brushed or brush-less, changes the direction of the current in the other winding to continuously alter the interaction between the two magnetic fields to allow the motor to rotate. In three-phase AC motors, the interaction between Read more [...]

Storing Data with Light

Currently, we have several methods of storing and transmitting data. The most common method followed is storing data on a magnetic hard disk in the form of bits. Here minute magnetic domains form a North and a South pole pair, with the direction of the magnetization of the poles defining whether the stored bit is a digital 1 or a 0. Writing the data means physically switching the magnetization of the relevant bit, one at a time. Switching or changing the magnetization of each bit requires the application Read more [...]

Contactless Magnetic Angle Sensing

Contactless magnetic angle position sensors are now giving optical encoders a run for their money. This was recently demonstrated by Monolithic Power Systems at Electronica 2018. They had on display a unique non-automotive-focused electric vehicle, mCar, with motion control and angular sensors. According to MPS, their mCar demos two main functions—motor control elements, and angular position sensors. As Quitugua-Flores, the mechanical engineer and primary designer of the mCar at MPS explains, Read more [...]