It is now believed that solar magnetic field is generated in the convection zone, or rather in its bottom where solar rotation changes from a solid-body rotation to a differential rotation (meaning that Sun's poles rotate faster than its equator). This change in rotation causes large velocity shears and turbulent motion of charged particles create electric currents and magnetic fields. Magnetic flux tubes rise to the solar surface. Large-scale flows closer to the surface transport eventually part of this field to the poles where it interacts with polar field changing slowly the overall polarity of Sun's magnetic field.

The solar dynamo theory has to explain many different features, such as 11-year sunspot cycle, butterfly diagram of sunspots (migration of sunspots towards equator as solar cycle progress), and the flipping of solar magnetic field polarity (north and south poles change place every 11-years).

Emilia