Choosing a brushless motor that suits specific needs requires consideration of multiple factors, including application scenarios and load characteristics Continuous or intermittent operation - If the motor needs to run continuously for a long time, such as in industrial ventilation systems or large server cooling fans, a brushless motor with good heat dissipation performance and high reliability should be selected. These types of motors usually use high-quality bearings and winding materials, which can withstand long-term working loads without overheating- For applications that operate intermittently, such as the opening and closing motors of automatic doors, although the requirements for continuous working ability are relatively low, the torque characteristics during frequent starts and stops still need to be considered. Intermittent operation motors should be able to provide sufficient torque to start the load in a short period of time and respond quickly to control signals during the stopping phase. 2. Load type - For constant torque loads such as conveyor systems, it is necessary to choose a brushless motor that can provide stable torque throughout the entire speed range. The torque speed characteristic curve of this motor is relatively flat, which ensures that the conveyor belt can transmit items at a constant speed and force- For constant power loads, such as the spindle motor of some metal cutting machine tools, the motor needs to maintain constant power at different speeds. This requires the selected brushless motor to automatically adjust torque according to changes in speed to meet the constant power demand- For square torque loads such as fans and pumps, the torque of the motor is proportional to the square of the speed. When choosing a brushless motor, it is important to consider whether its starting torque at low speeds and power output at high speeds can meet the load requirements. 2、 Performance parameter 1 Torque and speed requirements - Determine the required torque and speed range based on application requirements. For example, in the drive motor of an electric bicycle, sufficient torque is required to climb slopes and accelerate, while also having a suitable maximum speed to meet fast driving on flat roads. Brushless motors with corresponding torque and speed ratings can be selected by calculating the required torque of the load (based on factors such as load mass, friction coefficient, transmission ratio, etc.) and the expected operating speed- Pay attention to the peak torque and rated torque of the motor. Peak torque is the maximum torque that a motor can provide in a short period of time, used to cope with situations such as starting or sudden load changes; The rated torque is the torque at which the motor can operate stably for a long time. 2. Efficiency - For applications that are sensitive to energy consumption, such as electric vehicles or motors in solar power generation systems, efficiency is a key factor. High efficiency brushless motors can reduce energy waste and lower operating costs. View the efficiency curve of the motor to understand its efficiency performance under different loads and speeds. Usually, the efficiency is higher near the rated load and speed of the motor. 3. Power Requirements - Choose the power level of the brushless motor based on the power required by the load. The power (P) is equal to the torque (T) multiplied by the speed (ω), ensuring that the power of the selected motor can meet the operating requirements of the load under various working conditions. At the same time, a certain power margin should be considered to cope with possible overload situations or future application expansion. 3、 Motor size and installation method 1 Space limitations - In some compact devices, such as small drones or handheld power tools, space is very limited. It is necessary to choose a compact brushless motor, while ensuring that the external dimensions and installation method of the motor match the mechanical structure of the equipment. For example, some brushless motors adopt a flat design, which is suitable for installation in locations with limited spatial height. 2. Installation method - There are multiple installation methods for brushless motors, such as flange installation, bracket installation, etc. Select the appropriate installation method based on the design and installation requirements of the equipment. In industrial automation equipment, precise flange installation may be required to ensure the coaxiality of the motor and transmission components, in order to improve transmission efficiency and reduce vibration. 4、 Control method and compatibility 1 Controller compatibility - Brushless motors require a matching controller to operate. Ensure that the selected motor is compatible with existing or planned controllers. Different brands and models of motors and controllers may have differences in communication protocols, voltage, current, and other aspects. For example, some brushless motors use sine wave control and require a corresponding controller that can provide high-precision sine wave drive signals. 2. Control accuracy requirements - For applications that require precise control of position, speed, or torque, such as CNC machine tools or robot joint motors, brushless motors with high control accuracy should be selected. This may involve the encoder accuracy of the motor itself (if any) as well as the control algorithm and resolution of the controller. Some high-end brushless motors are equipped with high-precision encoders that can provide precise position feedback, and with advanced control algorithms, can achieve microsecond level control accuracy. 5、 Cost and reliability 1 The cost budget is based on the project budget to select brushless motors. There are significant price differences among motors of different brands, performance, and sizes. Try to balance performance and cost while meeting application requirements. For example, for some consumer grade products that do not require extremely high performance, such as ordinary household floor cleaning robots, cost-effective brushless motors can be chosen to reduce the overall cost of the product. 2. Consider the reliability and service life of the motor. For some critical equipment, such as motors in medical or aerospace equipment, reliability is crucial. Evaluate the reliability of the motor by examining its quality certification, production process, material quality, and other aspects. For example, brushless motors using high-quality bearings and insulation materials can maintain stability in harsh environments or long-term operation, reducing the probability of failure. At the same time, understand the maintenance requirements and maintainability of motors, and choose motors that are easy to maintain and have a longer service life.