System of proactive control of reactive power flows in distributed electrical grids

The paper solves the urgent problem of improving the methods and means of optimizing reactive power flows in distribution grids with significant daily volatility in the generation and consumption of electricity. The object of research is the process of automated control of a set of reactive power sources (RPS) in distribution electrical grids (DEG). Coordination of their operation will contribute to the reduction of electricity losses in the DEG and improve the voltage quality. Based on the results of the analysis of modern trends in the construction of RPS control systems, the expediency of decentralization using local automatic control systems (ACS) is substantiated. The operational determination of the optimal powers of the RPS and the calculation of the corresponding settings of local ACS are associated with objective difficulties. The study proposes a formalization of the problem of optimizing reactive power flows in DEG and a new way to solve it. It is shown that the problem can be reduced to the determination and periodic correction of the settings of local systems of automatic control of the RPS. The latter, by adjusting the energy flows according to local parameters, taking into account the specified settings, contribute to the achievement of the overall effect of reducing losses and stabilizing the voltage in the DEG. The proposed method contributes to a reasonable simplification and increase in the reliability of the distributed control system for reactive power flows in the DEG, taking into account technical limitations. To solve the problem, the principle of advancing control, the method of "ideal" current distribution (according to power losses) was applied. Using the model of "ideal" current distribution, the problem of nonlinear optimization of reactive power flows in the DEG was reduced to a fundamentally simpler problem of finding current distribution in a step-by-step circuit with active resistances. To determine the time intervals between the adjustment of local ACS, it is proposed to analyze the correlation between the predictive graph of the optimal power of an individual RPS and local energy consumption based on the Pearson coefficient. A block diagram and algorithms for the operation of the control system for the set of RPSs are proposed, which provide a minimum of computational operations and data exchange operations. At the same time, a response is provided to changes in the consumption and generation of electricity in the conditions of short-term failures of information systems. This contributes to improving the quality of operation of energy distribution systems in modern conditions.