Control of Multilevel Converter for AC Traction Substation with Power Symmetrization Unit

Abstract

This paper describes the control of multilevel converter for substation balancer. The topology of substation with electronic balancer is described. The principle of power symmetrization and reactive power compensation is introduced in paper. Designed control algorithm for independent current control is main goal of this paper. This control is based on the calculation of required current by Steinmetz's method. The paper presents simulation results of designed prototype of substation with rated power of 12.5 MVA for 25 kV / 50 Hz traction catenary.

Current Harmonic Analysis for AC Traction Substation with Power Balancer

“…This simulation of balancer is using discrete PS-PWM modulation and separated discrete control loop. The control algorithm is described in paper [10] and [11]. The created detailed simulation model, allows analysis of behavior, including the dead times issue.…”

Symmetrization Method of AC Traction Substation with Power Balancer

“…The main part of this paper is concern to derivation of the symmetrization method and equations required for the balancer unit. An extension of important knowledge for the already known topology and for the advanced topology, were presented in [1], [2], [3], [4], [5].…”

“…The first part of the paper describes common symmetrization method (Steinmetz theory) and defines the way in which the method for a controlled electronic balancer can be used (introduced in [2]). The second part of the paper describes the derivation of equations used for symmetrization and compensating of single-phase reactive load.…”

Symmetrization Method of AC Traction Substation with Power Balancer

“…However, the open delta configuration does not ensure full symmetrization, for these reasons new advanced TSS topologies are being tested in the Czech Republic. One perspective topology is traction substation with electronic balancer introduced in [1] and [2]. This paper deals with the AC TSS (traction substation) with electronic balancer.…”