Universal Converter Fundamentals

This information refers to the universal elevator inverter for industrial and general elevator inverter motor universal motor by the general power grid (single-phase 220V, three phase 380V 50Hz), elevator inverter for speed control. Such elevator inverter widely used in the industrial areas of the elevator inverter has become mainstream. The basic principle of speed based on the formula:
 
Formula (1): n1-synchronous speed (r / min);
f1-Stator frequency power supply (Hz);
       P-number of pole pairs.
General induction motor speed n and synchronization speed n1 exists a relationship between the slip
 
Formula (2) in: n-induction motor speed (r / min);
S-induction motor slip.
By the (2), we know that the method can change the speed f1, P, S which either reached the asynchronous motor is the best way to change the frequency f1, to achieve speed control.
By the motor theory, three-phase asynchronous motors rms per phase electric potential related with the following formula.
   
Formula (3): E1-Stator RMS per phase electric potential (V);
f1-Stator frequency power supply (Hz);
N1-effective stator winding turns;
Фm-stator flux (Wb).