In the process of operation, the frequency control motor fan ventilators can be divided into two types. In one type, the rotation speed of the motor is constant, and in the process of operation, a coupling capable of variable speed is installed between the blades and the motor. The other type is that the motor shifts the fan speeds together.
The speed control method of the motor of the VVF motor ventilator can be divided into AC speed regulation and DC speed regulation to a certain extent. The latter will also have brush DC motor speed regulation and brushless DC in the process of speed regulation. Motor speed control points; and in the AC speed control method, the more commonly used are pole-changing speed, cascade speed, frequency control and voltage regulator speed four.
The advantages of frequency control motor fan
1. Low loss and high efficiency.
In the process of manufacturing the frequency conversion speed regulating motor ventilator, the permanent magnet excitation is mainly used to effectively eliminate the loss caused by the excitation current of the induction motor to a certain extent, and at the same time, the permanent magnet brushless DC motor works in synchronization. The operating mode eliminates the transversal loss of the rotor core of the induction motor. These two aspects make the operating efficiency of the permanent magnet brushless DC motor much higher than that of the induction motor, and the efficiency of the small capacity motor is more obvious.
2. High power factor
In the process of operation, the frequency control motor fan will not need the reactive current of the grid because its excitation magnetic field of the brushless DC motor, so its power factor is much higher than the induction motor, and the brushless DC motor can operate at 1 power factor. This is extremely beneficial for low-power motors. Compared to induction motors, brushless motors not only have higher efficiency and power factor at rated load, but also have advantages at light loads.
3. Good speed control and simple control
Compared with the variable frequency speed control of the frequency conversion speed control motor fan and the induction motor, the speed control of the brushless DC motor is not only simple, but also has better speed control performance.
4. The inverter has low capacity, so the cost of the inverter is low
Frequency control motor fan to a certain extent is the need for a rectangular current, the current rating of the inverter during continuous operation is referred to as the peak value of this rectangular wave. Induction motors require sinusoidal currents. The current rating of the inverter during continuous operation is generally referred to as the RMS value of this sine wave.