Open circuit - Cogging torque

1. Positioning and objective

The aim of the test “ Characterization - Open circuit – Motor & Generator - Cogging torque ” is to get the characteristics of the cogging torque of the machine.

Thanks to this test it is possible to evaluate the impact of the machine topology (slots and magnets – number and dimensions) on the cogging torque characteristics (magnitude and period).

The following table helps to classify the test “Open circuit - Cogging torque”.

2. User inputs

No user input parameter is necessary to perform this test. Only the operating temperature of the magnet can be defined in settings.

3. Main outputs

Test results are illustrated with data, graphs and tables.

3.1 Table of results

1. Flux in magnetic circuit

   • Flux in airgap
   • Flux density in iron

2. Cogging torque

   • Characteristics (The cogging torque magnitude (peak-peak value) and its period)

3.2 Curves and graphs

• Cogging torque versus rotor angular position (over one cogging torque period)
• Cogging torque harmonic analysis (bar graph and table)