Jul 18, 2018
1. Technical performance. The motor can be started at a constant torque. The starting current can be limited below the rated current. The intelligent soft start is adopted. Since the torque is reduced to the second power of the voltage ratio, the startup torque is very small. Soft starter has current feedback, can also use constant current start, that is, in the process of starting to keep the starting current unchanged, until the motor is close to the synchronous speed. Considered from the aspects of technical performance, frequency control of motor speed startup is suitable for large starting torque load, is generally greater than the occasion, such as reciprocating air compressor, centrifugal separator, load conveyor, crusher, spiral, or such as rotary compressor, centrifugal fan, centrifugal pump, no-load start conveyor and various no-load start equipment.
2. Economy. The investment cost of inverter speed regulation startup is twice or even three times higher than that of intelligent soft startup.
Based on the above technical performance and economy, the latter is the starting mode that can be promoted by industrial and mining enterprises.