Method and apparatus for operating a dual rotor electrical machine

A method for operating a dual rotor electrical machine, the dual rotor electrical machine including a stator, an inner rotor including a first number of permanent magnet pole pairs, and a modulator including a second number of modulating segments and corresponding modulating rings, the method comprising:

• obtaining a first angular position of the inner rotor;
• obtaining a second angular position of the modulator;
• and
• determining a virtual position of an electromagnetic field of the stator, the virtual position based on a weighted sum of the first angular position and the second angular position, wherein weights in the weighted sum are based on the first number and the second number.

A non-transitory computer readable medium, when executed by a controller in a system including a dual rotor electrical machine having a stator, an inner rotor including a first number of permanent magnet pole pairs, and a modulator including a second number of modulating segments and corresponding modulating rings, is configured to cause the system to

• obtain a first angular position of the inner rotor;
• obtain a second angular position of the modulator;
• and
• determine a virtual position of an electromagnetic field of the stator, the virtual position based on a weighted sum of the first angular position and the second angular position, wherein weights in the weighted sum are based on the first number and the second number.