An electrical rotating apparatus comprises an inverter system that outputs more
than three phases. The apparatus further includes a stator electrically coupled
to the inverter system, and a rotor electromagnetically coupled to a magnetic field
generated by the stator. A signal generator generates a pulse modulated drive waveform
signal, that has a frequency synchronized with the rotational frequency of the
rotor, and the pulse modulated drive waveform signal drives the inverter system.
The pulse modulated drive waveform signal has a pulsing frequency. Additionally,
the inverter system may be fed by a pulse modulated drive waveform signal that
is fed through at least one signal delay device. Alternatively, the system may
also be fed selected harmonic components, such as the third harmonic, up until
the number of phases in the apparatus.
