The use of a topological list for calculating the parameters of electric-power systems on the basis of the node-voltage method

Abstract

The software implementation of the node-voltage equations for calculating the parameters of electric-power systems on the basis of the topological list is considered. Of the well-known modifications of the node-voltage method, it is proposed to use the equations for node voltages in the form of a current balance when specifying a constant-conductivity load. To eliminate the harmonic components during calculations, the equation for each element of the electric-power system is represented in the Park–Gorev axes. When forming the matrices of the nodal conductivities and specifying currents, a topological list that is based on the principle of piecemeal contributions is used. The key advantages of the method that is based on the topological list are that it is unnecessary to observe the order of numbering rows and that this method is highly algorithmic, thus providing the minimization of the computational efforts in compiling equations on a computer. The essence of the piecemeal-contribution principle lies in the successive formation of matrix coefficients, as row-by-row processing of the topological list is performed. An algorithm for the formation of equations according to the node-voltage method using the topological list in the form of a block diagram is presented. Calculation using the node-voltage method on the basis of the topological list is an independent task, as well as representing a component of more complex types of calculations, such as optimization of the normal modes, stability analysis, reliability assessment, etc. The interrelations between individual components of the process of solving the problem of calculating stationary and quasi-stationary operating modes of the electric-power system with respect to input and output information are shown. The formation of the equations of the structural elements in stationary and quasi-stationary modes of the electric-power system of a factory is based on the linearization of the initial node-voltage equations.