Calculation the dynamic stability zone of the distribution grid with generating sources based on renewable energy

Abstract

This study discusses the problems of ensuring the dynamic stability of distributed grids, including traditional generators, as well as renewable energy sources. Based on the energy distribution problem, an alternative regime model is formulated to calculate the steady-state in the distributed grid. Instead of using the state vector, it uses a calculated vector containing flows of active and reactive power for all branches of the grid’s equivalent circuit and nodal voltages. Test circuits of the distribution grid are drawn up for the power node with the possible connection of a solar power station and a gas turbine. It is shown that the appearance of heavy perturbations on the lines connecting these parts leads to a loss of dynamic stability. This creates new scarce and redundant parts of electrical grids. The possibility of the appearance of such areas is reduced with small (up to 30%) and large fractions (more than 85%). Therefore, in this range, it is advisable to concentrate distributed generation facilities in individual nodes of the power system.