In modern electric engineering development and implementing autonomous diesel generator sets is considered as a new technological trend. The article focuses on the functional scheme of a diesel generator power station with variable frequency of rotation and control systems, the application of which will allow reducing fuel consumption. The main control units of the proposed variant of the autonomous power plant are a logic device and a synchronizer. After switching the diesel generator on the parallel operation, basic functions of the logic device are to estimate loading and issuing a task for diesel generators. On the basis of the obtained data, the tasks of controlling the state of the generator automaton for the diesel generator, which is in priority over the start/stop, are performed. To evaluate the efficiency criteria, a graph of load power variation is given depending on the power of diesel generators, in which the optimal load intervals are determined. Such a distribution allows achieving reduction in fuel consumption and cost of electricity, providing an increase in the economic performance of an autonomous power plant. Despite the fact that the autonomous power plant has limited power, the proposed variant provides a load reserve in the range 15-110% and overload capacity in the range 13-43% of the total power of the diesel generator with constant speed. A graph of fuel consumption change depending on the active power consumed is presented. The basic interval of work with the minimum consumption of fuel is defined. For comparison, curves are shown that reflect the efficiency of using a diesel generator with variable speed as compared to a unit operating at a constant speed.