The brushless DC motor is not the earliest product, but developed on the basis of the brushed motor, and its structure is more complicated than that of the brushed motor.
The brushless DC motor consists of a motor body and a driver. It is different from a brushed DC motor. The brushless DC motor does not use a mechanical brush device, but a square wave self-controlled permanent magnet synchronous motor, and Hall sensors are used instead of carbon. The brush commutator uses NdFeB as the permanent magnet material of the rotor.
However, back in the last century, when the electric motor was born, the practical electric motor produced was in a brushless form.
1740s: The invention of the electric motor begins
Early models of electric machines first appeared in the 1740s through the work of Scottish Benedictine monk and scientist Andrew Gordon. Other scientists, such as Michael Faraday and Joseph Henry, continued to develop earlier electric machines, experimenting with electromagnetic fields and discovering how to convert electrical energy into mechanical energy.
1832: Invention of the first commutated DC motor
In 1832, British physicist William Sturgeon invented the first DC motor that could provide enough power to drive machinery, but its application was severely limited due to its low power output.
1834: Manufacture of the first real electric motor
Following in Sturgeon's footsteps, Thomas Davenport of Vermont made history when he invented the first official battery-operated electric motor in 1834. It was the first electric motor with enough power to perform the task, and his invention was used to power a small printing press.
In 1837, Thomas Davenport and his wife Emily Davenport received the first patent for a DC motor.
But their motor design still suffers from the same power and efficiency issues as William Sturgeon's. And unfortunately, due to the high cost of battery power involved, Thomas went bankrupt and the machine was not commercially available.
1886: Invention of the practical DC motor
In 1886, the first practical DC motor that could run at constant speed with variable weight was introduced. Frank Julian Sprague was its inventor, and it was this motor that provided the catalyst for the widespread use of motors in industrial applications.
It is worth mentioning that this practical motor adopts a brushless form, namely an AC squirrel-cage asynchronous motor, which not only eliminates sparks and voltage losses across the windings, but can deliver power at a constant speed. However, asynchronous motors have many insurmountable defects, so that the development of motor technology is slow.
Shortly after the brushless motor was born, people invented the DC brush motor. Because of its simple structure, easy production and processing, convenient maintenance and easy control, the DC brush motor became the mainstream at that time once it came out.
1887: AC induction motor patented
In 1887, Nikola Tesla invented the AC induction motor and successfully patented it a year later. It was not suitable for road vehicles, but was later modified by Westinghouse engineers. In 1892, the first practical induction motor was designed, followed by a rotating bar-winding rotor, making the motor suitable for automotive applications.
1891: Development of the three-phase motor
In 1891, General Electric began to develop three-phase induction motors. To take advantage of the wound rotor design, GE and Westinghouse signed a cross-licensing agreement in 1896.
1955: The era of brushless DC motors begins
In 1955, the United States d. Harrison et al. applied for the first patent of replacing the mechanical brushes of brushed DC motors with transistor commutation circuits, which officially marked the birth of modern brushless DC motors. However, there was no motor rotor position detection device at that time, and the motor had no starting ability.
1962: Invention of the first brushless DC (BLDC) motor
Thanks to advances in solid-state technology in the early 1960s, in 1962, TG Wilson and PH Trickey invented the first brushless DC (BLDC) motor, which they called a "DC motor with solid-state commutation". A key element of a brushless motor is that it does not require a physical commutator, making it the most popular choice for computer disk drives, robots, and airplanes.
They used Hall elements to detect the rotor position and control the commutation of the winding current, which made the brushless DC motor practical, but limited by the transistor capacity, the motor power was relatively small.
1970s to present: Rapid development of brushless DC motor applications
Since the 1970s, with the emergence of new power semiconductor devices (such as GTR, MOSFET, IGBT, IPM), the rapid development of computer control technology (MCU, DSP, new control theory), and the rapid development of high-performance rare earth permanent magnet materials (such as samarium With the advent of cobalt, NdFeB), the brushless DC motor has developed rapidly and the capacity has continued to increase.
After that, with the introduction of the mac classic brushless DC motor and its driver in 1978, and the development of square wave brushless motor and sine wave brushless DC motor in the 1980s, the brushless motor really began to enter the practical stage and developed rapidly.