Electronic Speed Controller Basics: Features, Funtions, Structures and Applications

The electronic speed controller (ESC) is an essential part of an electric propulsion system's hardware. It acts like the brain of the system by telling the motor how fast to go based on data signals it receives from the throttle controller. For smaller applications like drones and RC vehicles, this controller has the name "ESC", whereas for larger manufacturing applications it may be called an electronic control unit, inverter, or motor controller.

The mechanism within the ESC as well as its interaction with the battery and motor are quite fascinating. In this article, we will cover the fundamentals of the features, functions, structures and applications of the ESC.

What are the features of the ESC?

The features of the electronic speed controller are that it can independently determine the speed control characteristics, and can determine the best torque characteristics, idle speed characteristics and transition characteristics when all accessories are installed. The electronic dispatcher can meet the requirements of various models.

• The electronic speed controller has sensitive action, and a fast response, and at the same time, the time required only needs to be in the range of 1/10 to 1/2 of the hydraulic governor;
• Whether the ESC is dynamic or static, the accuracy is relatively high;
• It can be beneficial to realize remote control and automatic control;
• There is no governor drive mechanism, and the installation is relatively simple.

What are the structures of the ESC?

The electronic speed controller consists of a speed adjustment potentiometer, a speed sensor, a controller, an actuator, and a fuse circuit.

• Speed ​​sensor: It should acquire the highest possible signal frequency. The highest signal frequency is designed to be 12000Hz. The calculation formula of the relationship between engine speed and frequency is as follows: f=nz/60. In the formula, f--frequency Hz- engine speed r/min; Z- sensing gear teeth (or the number of teeth on the outer ring of the flywheel). The sensor should preferably measure the rotational speed from the flywheel, and the gap between the sensor and the tooth top of the flywheel ring gear during installation is 0.4-0.8mm.
• Controller: Its function is to compare the actual value of the speed measured by the sensor with the set value, and drive the actuator to execute.
• Speed ​​adjustment potentiometer: It is used to set the frequency according to the maximum allowable rpm the engine is using. If the operating frequency of the engine is specified when ordering, the factory will adjust the frequency according to the requirements. If the operating frequency of the unit is not specified on the order, the frequency is set to 2000Hz at the factory. If this set frequency is between the engine's idling and maximum speed, start the engine and adjust the "speed max" potentiometer to obtain the highest operating frequency of the engine.
• Actuator: The actuator is mainly composed of a DC motor, transmission gear, output shaft and feedback components. The actuator is driven by a DC motor, the torque of which is transmitted to the output shaft via an intermediate gear. The feedback component transmits the working state of the actuator to the controller to form a closed-loop control system. The rocker arm of the output shaft of the actuator is connected with the gear rod of the fuel injection pump through the adjusting connecting rod.
• Insurance circuit: There is a safety circuit in the electronic speed control system. When the sensing signal is interrupted, such as when the engine stops traveling due to cable breakage, it can stop the actuator and restore the output shaft rocker arm to the "0" position.

What are the applications of ESC?

Electronic speed control systems are used in remote control and vehicle applications. The main application of the ESC is the aircraft model, car model, ship model, and other remote control models. These models drive the motor to complete various commands through ESC, imitating its real working function, so as to achieve the effect similar to the real situation. Therefore, there are aircraft model ESCs specially designed for aircraft models, car model ESCs designed for car models, and so on.

• Electric cars
• Electric bicycles
• Electric aircraft
• Cars
• Helicopters
• Airplanes
• Boats
• Quadcopters
• ESC Firmware