What is a brush drill, what is a brushless electric drill, what is the difference?
It needs to be rectified before inverting.High power rectifiers and inverters are expensive, complex and unreliable processes that can burn hot.The current electric drill only need to use the switch control, on-off and power is enough.Finally, take a look at the current range of brushless motor applications.Brushless motors were originally developed by the British to improve the operational effectiveness of conventional submarines.The utility model has the advantages of small unit power, small volume and weight, low noise and high efficiency.
Although brushless motors have the advantages of long life and low noise efficiency, these advantages are not useful in electric drills.It is limited by the weaker magnetic force of the permanent magnet, and the brushless motor can not produce large torque, which is very fatal.Because an electric drill requires great torque to overcome the resistance of the drill.Finally, the system complexity.The power supply process of brushless motor is ac - DC - AC.
First of all, the cost problem, brushless motor drive device is very expensive (brushless motor itself is cheap), electric adjustment + motor one hundred to hundreds of pieces uncertain.Now, the AC excitation motor used by the electric drill doesn't use any microelectronic chip. It only uses copper wire and silicon steel sheet, which is very cheap.
