Design of asynchronous motors

We have developed design tools for asynchronous motors. Design is carried out based on the following input data:

  1. Number of phases (e.g. 3)
  2. Nominal power (e.g. 15kW)
  3. Nominal line voltage (e.g. 380V)
  4. Power supply frequency (e.g. 50Hz)
  5. Synchronous rotation speed (e.g. 1500rpm)
  6. International protection (e.g. IP54)
The developed design tools enable selection of a design strategy. This could be, for instance, a specific efficiency class. A starting torque ratio, a maximal torque ratio are assigned in accordance with standards. 

 

Our design tools allow:

1) automatic determination of optimal dimensions of a motor for a defined height of the rotation axis, namely: the outer and the inner diameters of a stator, length of the air gap, the active length of the stator, dimensions of the slots of the stator and of the rotor;

2) automatic determination of an optimal number of slots of the stator and of the rotor, an optimal number of turns in the stator winding, a cross-section of wire in the stator winding, and design and a winding diagram of the stator;

Our design tools allow:

1) automatic determination of optimal dimensions of a motor for a defined height of the rotation axis, namely: the outer and the inner diameters of a stator, length of the air gap, the active length of the stator, dimensions of the slots of the stator and of the rotor;

2) automatic determination of an optimal number of slots of the stator and of the rotor, an optimal number of turns in the stator winding, a cross-section of wire in the stator winding, as well as stator design and a stator winding diagram;

3) electromagnetic simulation of the motor and estimation of the no-load current;

4) automatic determination of the parameters of the equivalent circuit of the motor, estimation of a power factor for the nominal load, calculation of performance characteristics of the motor;

5) calculation of losses and the efficiency of the motor;

6) calculation of the starting characteristics of the motor taking into account skin effects and saturation of the magnetic circuit of the motor;

7) calculation of ventilation circuit of the motor;

8) thermal calculation of the motor;

Optimization calculation is based on prior successful designs of asynchronous machines and measurements conducted on existing asynchronous machines. Our design routines and optimization strategies have been verified through years of experience and actual tests. 

Thermal analysis is based on elaborate equivalent thermal circuit and graph theory.

Our design software allows the development of asynchronous motors in accordance with IE3 – Premium efficiency and IE4 – Super Premium efficiency as specified in IEC/EN 60034-30-1: 2014.

We are capable of designing a whole series of asynchronous motors in accordance with either IE3 or IE4 in a power range from 0.12 kW up to 355 kW for line voltage of 400 V.

Furthermore, we perform electromagnetic calculations of asynchronous motors in finite elements. Upon request, we could do a limited optimization of a selected set of parameters of asynchronous motors.

We perform mechanical analysis of shafts, housings, bearing shields. We can estimate mechanical forces acting on the stator winding during starting of the motor.

 

We can design and develop all the components required for the motor and provide drawings and accompanying documentation. We can provide both assembly drawings and drawings of specific components. If the customer wishes to reuse some of his available parts, we could adjust our design accordingly.

We can develop asynchronous motors in accordance with any of the following implementations: IP54, IP55 or IP23.

We can design asynchronous motors for a line voltage of over 1000 V and for powers of over 355 kW and up to 10 MW.