A brief introduction about ec fan motors
With the development of society, whether it is air source heat pumps, axial fans, or new air ventilation systems, home air conditioners, commercial air conditioners, and ec fan motors can be seen.
Ec fan motor power supply is AC power, built-in DC to AC (through six inverter modules), using rotor position feedback, three-phase AC, permanent magnet, and synchronous motor. (DC brushless is only the appearance of power quality and motor, not the substance of the motor,ec fan motor is essentially a three-phase AC permanent magnet synchronous motor.
Ec fan motor is a brushless, maintenance-free motor with a built-in intelligent control module. It has an RS485 output interface, 0-10V sensor output interface, 4-20mA speed control switch output interface, alarm device output interface, and master-slave signal output interface. The product has the characteristics of high intelligence, high energy saving, high efficiency, long life, low vibration, low noise, and continuous, uninterrupted work.
The brushless motor is greatly simplified in structure because the collector ring and brush for excitation are eliminated. At the same time, life is increased, the EC fan motor process is improved, and the mechanical reliability of motor operation is improved.
At the same time, the air gap magnetic density can be greatly improved, the motor index can achieve the best design, and the direct effect is the motor size reduction weight reduction. In addition, it has excellent control performance compared to other motors. This is due to the following:
(1) Due to the performance of permanent magnet materials and the motor torque constant, torque inertia ratio, power density, etc., greatly improved. Through reasonable design and can make the rotational inertia, electrical and mechanical time constants, and other indicators can be greatly reduced, as the main indicators of servo control performance have been greatly improved.
(2) The modern permanent magnet circuit design has been more perfect, coupled with the high coercivity of permanent magnet material. Thus the resistance of the permanent magnet motor to armature reaction and its ability to resist demagnetization is greatly enhanced, and the control parameters of the motor with external disturbances are greatly reduced.
(3) Since permanent magnets are used instead of electric excitation, the design of excitation winding and excitation field is reduced, thus reducing the excitation flux, excitation winding inductance, excitation current, and many other parameters, which directly reduces the controllable variables or parameters. Combining all these factors, it can be said that permanent magnet motors have excellent controllability.
At present, there are many large-capacity fans to adjust the air volume using the variable frequency speed control. This type of frequency converter mainly depends on imports, expensive. Currently, 1kw below the power level of the fan, especially the home air conditioning fan, has a permanent magnet brushless motor drive and the use of speed regulation air volume way. 1 ~ 10kw power range of the fan dosage is huge, the basic use of induction motor drive, and the use of adjustable air opening way to adjust the air volume. For this power range of the fan, the use of a permanent magnet brushless motor drive instead of the original induction motor drive has great superiority.
(1) Small loss and high efficiency.
Because of the use of permanent magnet excitation, eliminating the loss of induction motor excitation current; at the same time, the permanent magnet brushless motor works in synchronous operation, eliminating the loss of induction motor rotor iron core rotation frequency. These two aspects make the operation efficiency of a permanent magnet brushless motor much higher than that of an induction motor, and the efficiency improvement of the small-capacity motor is more obvious.
(2) High power factor.
Since the excitation field of a brushless motor does not require reactive current from the grid, its power factor is much higher than that of an induction motor. A brushless motor can run at one power factor, which is extremely beneficial to small power motors. Compared with induction motors, brushless motors have higher efficiency and power factor at rated load and more advantages at light load.
(3) Good speed control performance and simple control.
Compared with the frequency control of the induction motor, the speed control of the brushless motor is not only simple but also has better speed control performance.
(4) The inverter capacity is low, so the inverter cost is low.
Brushless motors require a rectangular wave current, and the current rating of the inverter during continuous operation refers to the peak value of this rectangular wave. The induction motor needs sine wave current. The current rating of the inverter during continuous operation generally refers to the RMS value of this sine wave. To maintain the inverter's ability to control the motor current, there should be enough difference between the inverter DC voltage and the motor induction potential. Therefore, the peak values that can be reached by both the brushless motor's trapezoidal induction potential and the induction motor's sinusoidal induction potential are limited by the inverter DC voltage. In this case, if the peak values of the brushless motor and induction motor currents are assumed to be equal, the power output of the former is 33% higher than that of the latter, i.e., the same rectifier/inverter can drive a brushless motor with 33% higher power output than that of the induction motor.
The above is the knowledge about ec fan motor. If you need more detailed information, welcome to contact us!