Are there 3 harmonics in the voltage of a three-phase alternator? Why?

Are there 3 harmonics in the voltage of a three-phase alternator? Why?

If the generator is loaded and the load has another 3 harmonic generation, then there may be 3 harmonics in the outlet voltage when the generator is loaded;

If the generator is connected to the power supply system after the transformer is boosted up, and the transformer has a winding with a triangle connection, then there is no 3 harmonic in the generator outlet voltage

If the generator is delta connected, there is no 3 harmonic in its no-load voltage;