1. Stable Air PressureVariable speed screw air compressors utilize the stepless speed regulation function of inverters, allowing them to operate stably via a controller or the built-in PID regulator in the inverter. In scenarios where air demand fluctuates significantly, they can respond and adjust quickly. Compared with the on-off control of fixed-speed air compressors, the air pressure stability of VSD models is improved exponentially.

2. No Startup ShockInverters themselves integrate the function of a soft starter, so the maximum startup current is within 1.2 times the rated current. In contrast, the startup current of fixed-speed air compressors is generally more than 6 times the rated current—meaning VSD models have much smaller startup shock. This shock will greatly reduce its impact not only on the power grid but also on the entire mechanical system.

3. Variable Flow ControlFixed-speed air compressors can only operate at one discharge volume, while VSD air compressors can work within a wide range of discharge volumes. The inverter can adjust the motor speed in real time according to the actual air demand to regulate the discharge volume. When the air demand is low, the air compressor will automatically enter sleep mode, which significantly reduces energy loss. The energy-saving effect is further enhanced through optimized control strategies.

4. Better Adaptability to AC Power VoltageThanks to the over-modulation technology adopted by the inverter, when the AC power voltage is slightly low, the inverter can still output sufficient torque to drive the motor. Even if the field pressure is slightly higher, the voltage output by the motor will not be excessive. In terms of magnetoelectric generation, VSD drives can better demonstrate their advantages. Based on the V/F (Voltage/Frequency) characteristics of the motor (VSD air compressors operate below the rated voltage in energy-saving mode), their performance is particularly noticeable in sites with low grid voltage.
5. Low NoiseVSD systems operate at speeds lower than the rated speed in most cases, which reduces the mechanical noise and wear of the main unit—thereby extending the maintenance interval and service life. The fan also uses a variable speed drive, which greatly reduces noise during the air compressor’s operation.