Development Status of Brushless DC Motor-2
DC motors have been widely used in the field of motion control due to their excellent torque characteristics, but ordinary DC motors have poor reliability and require frequent maintenance due to the need for mechanical commutation and brushes. It affects the further application of DC motor in control system. In order to overcome the shortcomings brought by mechanical commutation, the brushless motor that replaces mechanical commutation with electronic commutation came into being.
In 1955 the United States D. Harrison et al. applied for the first patent for replacing mechanical brushes with transistor commutation circuits, marking the birth of modern brushless motors. The electronically commutated brushless DC motor really entered the practical stage with the introduction of the MAC classic brushless DC motor and its driver in 1978. After that, in-depth research was carried out on the brushless DC motor in the world, and the square wave brushless motor and the sine wave DC brushless motor were developed successively.
Over the past 20 years, with the development of new permanent magnet materials, microelectronics technology, automatic control technology and power electronics technology, especially high-power switching devices, brushless motors have made great progress. The brushless DC motor no longer specifically refers to the DC motor with electronic commutation, but generally refers to the electronic commutation motor with the external characteristics of the brushed DC motor.