Development Directions of Power Supply for Rural Areas of Tajikistan

The article discusses the structure of small hydropower plants (HPP) recently built in Tajikistan. The problems arising in the course of their operation are noted. It is proposed to solve these problems to reconsider the HPP structure so that they can be operated in a stand-alone unattended mode, using simple and reliable basic energy conversion elements. The authors suggest using a centrifugal pump as a turbine, without regulating the rotational speed. The absence of a turbine speed regulator containing movable mechanical devices for regulating the flow of water to the turbine will significantly increase its reliability and simplify state diagnostics operations. As a generator, it is suggested using an unregulated synchronous machine with excitation from permanent magnets. The application of a generator consisting of two structurally complete units, a rotor with permanent magnets and a stator with a winding will also increase its reliability, significantly increase the time of interregional checks, simplifying them. The required output voltage quality and high reliability must be provided with a semiconductor converter. In order to diagnose the state of a power plant, it is proposed, in addition to sensors for mechanical, thermal and electrical values, to include in its composition a complete mathematical model, that is, its digital twin and diagnostics to be carried out, including on the basis of comparison of measured actual and received values from a digital twin. The article also shows the problems arising in the implementation of the proposed structure, and ways to solve them.