Electronic Speed Controller (ESC) Unit One of the most important parts which used to control the speed of motors. ESC controls the number of Revolutions per minute RPM synchronize with user-pilot defined signals. The selection of ESC is the second step after selecting the Brushless DC Motor. It is the link between the Transmitter unit of the RC aircraft radio system and the receiver unit with the LIPO battery. The pilot controls the throttle by the transmitter and then sends the signal to the receiver, and the receiver sends the signal to the ESC to control the motors speed. ESC have lots of applications usually used in:
- RC Aircrafts: Airplane, Drone, Helicopter.
- RC Vehicles: Car, Truck, Tank.
- RC Boats.
ESC Connections Methods
ESC used in Brushless DC Motor because ESC can provide the motor with low and high voltage gradually protecting the motor from damage. Choosing an ESC is easy, but before we talk about choosing it, we will talk about ways of connecting the ESC with aircraft there are two methods the first directly with remote control and receiver when the receiver receives the signal from transmitter then ESC Take the signal to control the motor directly Like the following picture:
The second way is using electronic controllers such as (Microcontroller, Arduino and raspberry pi). For added entertainment, for example, when adding sensors, not all of them support radio tools, so it is necessary to use other controllers sometimes, such as the following picture shows connecting the electronic speed control unit with the Arduino:
Now we will discuss the specifications required to choose the ESC Unit. the following picture examines the pins and direct connection:
ESC selection is similar to the motor selection process approximately, So when buying an ESC we consider on the following Specifications:
When selecting ESC, the current must be higher than the current used by the motor, for example, if motor needs current 40A, You will buy 50 or 45 Amp instead of 40 In order to protect the ESC from damage due to overheating when opening the throttle to the maximum.
Like the Brushless DC Motor, there is a Recommended lipo-battery for use, You must choose the right battery to get the highest RPM provided by the motor.
Usually, we don’t focus on ESC weight Because it is very light, but we care about dimensions to be suitable for the aircraft. All components (Brushless DC Motor, LIPO Battery and ESC) Suitable dimensions to install in the right place and there is a distance between them and electronic parts to avoid overheating.
Some types of electronic speed control units control custom types of motors such as Brushless DC Motor, Brushed DC Motor or AC motors.
Now let ‘s consider choosing an electronic speed control unit, for example, we will take the (ZTW ESC 60A) model from amazon, You will notice the following information:
|Size||56mm x 30mm x 14mm (LxWxH)|
|Battery||2-6S Lipo / 5-18NC|
|Current||60A, peak 70A (10 seconds MAX)|
|BEC output||5A/5.5V, peak 5A|
|Motor Type||Brushless (no brushed)|
|RPM support||200,000 for 2 P ,82,000 for 6 P,42,000 for 12 P.|
|Connector Soldered||1 x XT60 for power side ,3 x 3.5mm female for motor side.|
Do not forget to take a safety factor in choosing an electronic speed control unit to control the motor, for example, if the motor wants a 50 amp ESC unit, You will increase the value to be 55 or 60 Amp.