FPV Drone Motor Efficiency

Why doesn’t the clock ring?

As mentioned earlier, the rotor of the brushless FPV driverless motor is composed of a circular magnet array and a central shaft. When the motor is assembled, the shaft protrudes from the base of the motor. Here, it is held in place by a snap ring or tight bolt. Clasps are the most commonly used, but bolts are becoming more and more popular. Although the retaining ring has been the main choice, maintenance can be frustrating due to the difficulty of removal. The snap ring is fragile, small in size and easy to be damaged or lost.

Speed constant the speed at which a motor rotates

The speed constant (kV) determines how many revolutions a motor can rotate in a minute without a load (propeller) at a constant current of 1 volt. In short, kV is the potential rotational speed of the motor. The kV of the motor is determined by the magnetic field strength at the stator and the number of turns in the winding. Low kV motors are most suitable for driving heavy propellers efficiently. High KV motor is optimized for light propeller.

thrust

Thrust is one of the key factors to be considered when selecting motor. The thrust output of a motor is usually expressed in grams and varies according to the rotational speed of the motor and the propeller. Before the helicopter starts to accelerate, it needs a certain amount of thrust to overcome resistance and gravity.

Weight and momentum of FPV drone Engine

When selecting a motor, it’s not all about thrust numbers. The weight of the motor should also be taken into account because it has an important influence on the flight characteristics of multiple aircraft. Because of the moment of inertia, the heavier motor is more resistant to the change of acceleration than the lighter motor. The main problem of heavy helicopter engine anti acceleration is that once it flies into the air, it will provide inaccurate flight characteristics and poor responsiveness. If mobility is a priority, then light motors are a typical choice. On the other hand, in applications, maximum full speed is required; a larger engine will be able to provide the higher thrust figure required.

Motor response time of FPV drone

Torque is a measure of the speed of the motor to reach a certain speed, which directly affects the response ability of the motor. Torque allows a helicopter to flip and roll, in addition to improving the accuracy of these movements. The output torque of motor will also affect the choice of propeller. Heavier props need more torque to accelerate than lighter props. The size of stator is the best measure of motor torque. Larger stators tend to produce larger torques. Although a larger stator will increase the total weight of the motor.

Motor efficiency of FPV drone

Motor efficiency is a kind of balancing behavior, which needs to balance the power entering the motor and the mechanical power generated when the motor rotates. The importance of motor efficiency varies from case to case. If high speed is a priority, short flight time is generally considered acceptable; the FPV four axis aircraft race may only last two minutes! On the contrary, long-range FPV helicopters need maximum efficiency to achieve longer flight time, thus increasing the distance they can fly.