Motor driving principle: A motor (commonly known as a "motor") refers to an electromagnetic device that converts or transmits electrical energy based on the law of electromagnetic induction. Its main function is to generate driving torque as a power source for electrical appliances or various machinery.

Place a coil in a magnetic field, and through the flowing current, the coil will be repelled by one magnetic pole and attracted by the other magnetic pole, continuously rotating under this effect. During the rotation process, the current flowing into the coil is reversed, causing it to rotate continuously. This is the most basic principle of motor operation

Brushless DC Motor (BLDC)

The term "BL" in BLDC motors, also known as "Brushless," is translated as brushless. The "brush" in the DC motor is gone. The role of the brush in a DC motor is to apply electricity to the coil in the rotor through a commutator. So how does a BLDC motor without brushes energize the coils in the rotor?

BLDC motors use permanent magnets as the rotor, and there is no coil inside the rotor. Due to the absence of coils in the rotor, there is no need for commutators and brushes for energizing. Instead, the coil serves as the stator. The BLDC motor controls the rotation of the rotor by controlling the direction and magnitude of the current flowing to the coil.

Advantages and Applications of BLDC Motors

The first advantage of BLDC motors is their "high efficiency". It can maintain the maximum turning force (torque) at all times. The maximum torque of a DC motor can only be maintained for an instant during rotation and cannot always maintain its maximum value. If a DC motor wants to obtain the same torque as a BLDC motor, it can only increase its magnet. This is why small BLDC motors can also emit powerful power.

The second characteristic is' good controllability ', which is related to the first one. The BLDC motor can provide precise feedback on target rotation, torque, etc. Accurate control can suppress the heating and power consumption of the motor. If it is battery driven, the driving time can be extended through careful control.

The above two points are the advantages brought by brushless and commutator. In addition, BDLC also features durability and low electrical noise. If noise is not desired during use, a BLDC motor can be used to achieve this.

According to Grand View Research, the BLDC market size can reach $22.3 billion in 2025. With the maturity of technology, BLDC motors have been widely used in military, aviation, industry, automobile, civil control systems, and household appliances. Low voltage and low-power devices are commonly seen, such as small robots, drones, electric bicycles, vacuum cleaners, electric tools, etc.

Silijie BLDC Motor Drive Scheme

As a leading global manufacturer of high-performance analog chips, SiliJie has leading technologies and numerous chip solutions in various fields such as automotive electronics, industrial control, communication computing, and consumer electronics. SY67343 is a new generation of three-phase non-inductive sine motor driver chip launched by SiliJie. It uses built-in MOS and operates at a maximum driving current of 2A, supporting various motor types such as permanent magnet synchronous motors and brushless DC motors. In addition, SY67343 also supports various protection functions, such as overcurrent protection, undervoltage protection, and over temperature protection, comprehensively ensuring the safety of the motor and chip during use.