AXIAL TYPE ELECTRIC MACHINE WITH PERMANENT MAGNETS

The development of new technique and technology puts forward new requirements for electrical
machines, which vary depending on their area of application. Among them, the most important ones can be
distinguished, namely: increasing the speed control range; increase in dynamic performance by increasing
the achieved acceleration; increasing the specific electromagnetic moment; reduction of electromechanical
and electromagnetic time constants; increasing efficiency and reliability, quality and accuracy of
reproduction of dynamic states (quality of controlled and programmed motion); reducing the volume and
weight of an electric machine while maintaining the original parameters; obtaining high utilization rates of
both volume and active materials of an electric machine; reduction of noise and vibration generated during
the operation of an electric machine; obtaining maximum electromagnetic compatibility.
Traditional electrical machines in some cases cannot satisfy the above requirements. Therefore, to
correspond the current increased requirements in the area of automation of technological processes, in
automation and robotics systems, in special electric machines for transport systems, in electric generators for
wind generators and hydroelectric power plants, a new knowledge base in the field of modern
electromechanics, advances in power- and micro- electronics, computer science, materials science should be
used to create new types of electrical machines with significantly increased specific characteristics.
Permanent magnet motors are widely used in many areas of technology, for example, in the electric
drive of transport systems, ship technology, aviation, while the production of such motors is increasing every
year. The specific indicators of these electric motors (Nm / kg, kW / kg, W / m3) are continuously improved
both by optimizing the magnetic system and by using liquid or mixed (liquid + air) cooling. Large
international companies are mass-producing liquid-cooled and air-cooled permanent magnet motors.
An electric machine with axial magnetic flux and an innovative double stator has been developed,
the design of which allows obtaining high specific characteristics at the level of the best world samples. An
electric machine can operate in both generator and motor modes. The main parameters of the electric
machine for the AC mode (forced air cooling) are given in the table, the external view of the axial type
electric machine with permanent magnets is shown in the figure.

ParameterValue
Diameter [mm]240
Width [mm]112
Volume [m3]Volume [m3]0.005
Rotation speed [RPM]3000
Continuous motor power (mode АС) [kW]45
Power density (mode АС) [kW/m3]8886
Motor efficiency [%]92-95
Input phase wire cross-section [mm2]7.5
Continuous motor current [Arms]75

As a result of a variant analysis of the geometry of the magnetic system when modeling the magnetic field and calculating the electromagnetic moment from the angle of rotation of the rotor, the optimal dimensions of the magnetic system were determined, which ensure the specific characteristics of the proposed electric machine at the level of the best world samples.