A new approach to control of voltage levels and reactive power compensation in 110—220 kV grids
Abstract
Today, there are a lot of adjustable components in power grids, which include generators, synchronous and static reactive power compensators, static capacitor banks, transformers with longitudinal voltage control and with combined voltage magnitude and phase shift control, and shunt reactors. The difficulties of performing dispatch control of such a variety of controllable components, which are stemming from the complexity of calculating their optimal control modes, are further aggravated by the complexity and highly branched configurations of network circuits, a large number of operating parameters to be monitored, and the necessity of taking into account a random and indefinite composition and state of initial data. An excessive burden imposed on the dispatch control operators by the amount of incoming data and information links may adversely affect the reliability of power grid operation. In order to improve the power grid operational reliability, it is proposed to reduce the information burden imposed on the dispatch control operators by setting up automated control of voltage levels within the dispatch control center’s coverage area. The approach to solving the problem of setting up automated voltage control includes a few stages: studying the volt/VAR operating mode optimization methods, elaborating a voltage control algorithm based on the most efficient volt/VAR optimization approaches, and designing an automated voltage control system operating in accordance with the elaborated algorithm. The article presents the results from an analytic investigation of the matrix of voltage sensitivity coefficients carried out for the test 110—220 kV grid. The obtained results corroborated the hypothesis about the possibility of determining---based on the values of matrix elements---the grid nodes the control of voltage and reactive power at which has the most efficient influence on the active power losses in the test grid. An algorithm for centralized control of voltage levels and reactive power in 110—220 kV grids is proposed. The proposed algorithm can be used for setting up a centralized voltage control system that would make it possible to achieve better control of the power grid operating mode by increasing the number of voltage checkpoints in the grid and reduce the information burdens imposed on the dispatch control operators by automating the voltage control process.
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