Electric motors can be divided into DC motors and AC motors. DC motors Brushless DC motors and brushless DC motors. AC motors include asynchronous induction motors and synchronous motors. The mechanical characteristics of different motors are different. For different usage scenarios, the mechanical performance of the motors can be selected to match.
For production machinery with stable load and no special requirements for starting and braking, ordinary squirrel cage asynchronous motors should be preferred, which are widely used in machinery, water pumps, fans, etc.
In order to start and brake more frequently, production machinery that requires larger starting and braking torque, such as bridge cranes, mine hoists, air compressors, and irreversible rolling mills, should use wound asynchronous motors.
Where there is no requirement for speed regulation, and where constant speed or power factor improvement is required, synchronous motors should be used, such as medium and large-capacity water pumps, air compressors, hoists, mills, etc.
The speed range requirement exceeds 1:3. For production machinery that requires continuous, stable and stable speed regulation, other excitation DC motors or squirrel cage asynchronous motors should be used with variable frequency speed regulation or synchronous motors, such as large precision machine tools, planers, rolling mills, and hoists. Wait. .
The production machinery that requires large starting pitch and soft mechanical characteristics uses series or composite DC motors, such as trams, electric locomotives, heavy cranes, etc.
In order to achieve high precision, DC stepper motors and servo motors, such as robotic arms, can be used.
In the process of motor selection, cost is also a very important consideration. As the domestic AC frequency converter technology is mature, the price is gradually decreasing. The combination of variable frequency motor and frequency converter has been widely used because of its simple structure, good speed regulation performance, and low maintenance cost.