In terms of quantity, renewable energy sources can fully satisfy the needs of mankind. But, as is known, they, along with power converters, degrade the inertia constant of the power system and complicate the operation of the power system automation. To resist this, existing generators should be remodeled by somehow increasing their inertia or by installing non-load generators (quasi-generators) or by applying synthetic sources of inertia. The increase in the angle δ of the synchronous generators from a smoothly sloping change in the load, which is provided by the quasi-generators, is several times less than from an abrupt change of the load with the same value and duration. The counteraction to a decrease of inertia is most effective when it is carried out directly at the site of the disturbance, i.e., where abrupt power changes occur. Inertia constant of synchronous machines differs less when the dimensions of the machines with greater rated power are more compressed in the axial direction.