The study of transient processes in discretely adjustable setting reactive power compensation

Abstract

The results of the analysis of transients in a two-stage installation of transverse capacitive compensation of reactive power 3 and 6 MVAr in the AC traction network with a voltage of 25 kV are presented. The first stage of compensation 3 MVAr ($\mathbf{C}=12\ \boldsymbol{\mu} \mathbf{f}$) is the subsequent inclusion of two CL sections and the second stage 6 MVAr ($\mathbf{C}=24\ \boldsymbol{\mu} \mathbf{f}$) is the inclusion of only one CL section. The first stage is activated at low loads to reduce power losses, and the second stage – when driving heavy trains to increase the voltage in the traction network. The analysis of transients is carried out in the integrated MATHCAD package by solving nonlinear differential equations in the form of Cauchy by the fourth-order Runge-Kutta method with a constant integration step. The values of current and voltage surges during shunting of the damping resistor and one CL section at different times are determined. Recommendations on the choice of the moments of switching on and off of fast-acting switching devices to reduce the current and voltage surges on capacitors are given.