Advantages of air compressor equipped with permanent magnet synchronous motor
1. High efficiency
The high efficiency mentioned here does not only mean that the efficiency of the rated power point is higher than that of the ordinary three-phase asynchronous frequency modulation motor, but refers to its average efficiency in the entire speed range. The excitation field of the permanent magnet synchronous motor is provided by the permanent magnet. No excitation current is required, and the efficiency of the motor is improved. Compared with asynchronous frequency conversion speed regulation, any speed can save electric energy, especially when the speed is low. This advantage is especially obvious.
2. Small starting current, large starting torque
According to the characteristics of the inverter, when starting at low frequency, the main magnetic field of the asynchronous variable frequency speed control motor is low, the power factor is low, the starting current is large, but the starting torque is small; the main magnetic field of the rare earth permanent magnet synchronous variable frequency speed control motor is constant, and the stator The current is almost all active current, the starting current is small and the starting torque is large.
3. Good performance index
The power index of the motor refers to the product of the efficiency of the motor and the power factor. It represents the power index of the motor. When the asynchronous variable frequency speed control motor works under load, its efficiency decreases. The power factor decreases. The efficiency and power factor are similar to a horizontal curve. Even when the motor is only loaded, the power index of the rare earth permanent magnet motor is still above the full load, which further improves the efficiency of electric energy use and the quality factor of the power grid.
4. Small size, heavy basin and light
Due to the use of high-performance permanent magnet materials to provide the magnetic field, the air gap magnetic field of the permanent magnet motor is greatly enhanced than that of the induction motor. The volume and weight of the permanent magnet motor can be greatly reduced compared with the induction motor. For example, the weight of asynchronous motors is equal to the weight of permanent magnet motors.
Based on the above comparative advantages, at present, equipped with a permanent magnet synchronous motor is the best choice for a variable frequency drive motor, which is more efficient and energy-saving than an ordinary three-phase asynchronous variable frequency motor!