With the decline of brushless prices and the rise of domestic brushless, the brushless era is getting closer to our RC model players, but there are also a lot of people who don’t know much about the brushless.
One, what is brushless?
The so-called brushless, that is, no carbon brush, is used to distinguish from the general brush motor.
The conventional motor, that is, the brush, is usually fixed to the motor, using the motor cover and the motor, fixed the rotor of the winding (usually 3 wings), and then through the brush and the rotor head contact, the conductance to the rotor, producing a mutually exclusive magnetic field, so that the rotor rotates.
Without brush, the permanent magnet magnet is made into the rotor, and the winding of the coil can be changed without brush, and the change of the magnetic field of the coil can be changed to drive the rotor to rotate.
As a result, the brushless motor needs 3 wires to connect to the motor, because it needs to adjust the magnetic field of the coil, and the brush motor only needs 2 lines to the motor, because the rotor’s magnetic field is automatically converted when the rotor rotates. Therefore, there are brushes, not brushless; brushless electricity can not generally use brush, but also some brushless power can support the brush motor, the specific reference to the parameters of electrical adjustment.
Two, what is inner rotor brushless and outer rotor brushless?
The so-called inner rotor, is the coil around the motor outside, the rotor into a bar, fixed in the motor, is the inner rotor brushless motor, see GTB motor.
While the outer rotor is placed inside the coil winding, the magnet is made into a special shape and rotated around the inner coil on the outside. There are many examples. Just like the fan inside the computer, the outer rotor is brushless.
Our car brushless motor, usually the inner rotor brushless motor, does not require a special torque, high speed; and the outer rotor is especially suitable for the aircraft, the torque is large, especially suitable for the needs of 3D flight.
Add a small point, on the motor angle problem, whether there is brush or brush, there is an angle problem, can refer to this post: http://bbs.rcfans.com/viewthread.php? Tid=98030
Three, what is the KV value? What is the number of T? What is R?
Brushless parameters are generally marked with KV values. The KV value is the speed indicator of brushless motor, which means the value of motor speed increases with increasing 1V voltage.
For example, 4000KV brushless, loading the general car with lithium 8V around, the speed of 4000*8=32000 turn (23T brushes about this speed), so the current competition allows the 4000kv brushless and 23T in the same game.
Like the brush motor, the value of the coil winding is T, or R (NOVAK is expressed by R, and many others are represented by T). Generally, the number of brushless T (or R) is equivalent to that of 2 times the number of brushes. For example, 3.5T brushes are equivalent to 7T brushes (specific principles and why no brush often has “.5T” T before Himalaya brothers explained in a post in the trolley area, I forgot the title of the placard, and now it cannot be searched out).
The same brand, the T number and the KV value are generally fixed, unless the manufacturer improves, and different brands, the T number and the KV value is not necessarily linked, such as LRP 3.5T is more than 9000 KV, and NOVAK 3.5R is more than 10000 KV. I think the main difference between the output power and the power of the motor is that the speed will not be very different. This is what physics teaches. In fact, I haven’t compared it.
Vehicle brushless system, I recommend a gentle way to play more, RV with 2S lithium battery is good, even 4000kv, speed is also good. If two people play with a trolley, 23T will continue to fight for 10 minutes. 11.1V voltage is not very suitable for use in the car, blindly increasing the voltage to improve the speed of brushless motor, although it may make the car’s tail speed high, but not to improve the technology and speed of the loop, we are not just to run straight to the straight line right? In fact, I don’t like the way to sacrifice everything for a straight line. Driving technology is not good, the faster the speed, the faster the loss, the longer the car repair, the higher the cost.
Four. Brushless and brushless Brushless
Quote Comrade JOVI’s original saying: “brushless electric modulation must know the current position of the rotor before it can output the appropriate current to drive the motor. The sense is to sense the rotor’s current position (phase) by inductor mounted on the motor. Without sense, there is no inductor, and the electric current depends on the power line to judge the rotor phase. (see http://bbs.rcfans.com/viewthread.php? Tid=112452 for details)
There is a sense of phase, so the linear is much better than no sense of sense. All the players who have no sense of feeling are well aware that the usual brushless start is less linear and even a bit more violent, but there are some non sense linearity, such as the homemade wolves series non sense series, and the other NOVATECH products in China. Cards, according to friends who work in the KYOSHO plant, low speed linearity is