The broadband frequency characteristics of major equipment in the ±800 kV converter station and their influences to the short-circuit fault transient

Analysis and Design of Damping Circuit Parameters for LCC Valves Based on Broadband Model

“…Besides, the stray inductances L ts of transformer windings are included in L t1 and L t2 . Model parameters could be obtained from filed tests [29].…”

“…The coupling effects between components inside the converter valve are represented by the stray capacitances C vv . Parameters of stray capacitances can be obtained by filed measurements or electromagnetic field calculations [29]. Figure 3d depicts the broadband model of the smoothing reactor.…”

Influence of lightning surges on wideband‐frequency model of LCC‐UHVDC converter station

“…These stray capacitances influence and get activated on HFs, giving rise to capacitive coupling between the valve modules and on various locations. A detailed account of such stray capacitances is tabulated in Table 4 [6]. The operating principle of valves is like an inductor of solenoid type in case the valves are conducting given as where the cross‐sectional areas of current loop are denoted by xy , N represents the layer number of valve tower, z is the valve layers' length and denotes the permeability of air core.…”

“…The authors in [5] investigated the low‐frequency (LF) characteristics which consider the nameplate parameters while ignoring the frequency‐dependent wideband (WB) model of the converter station. The existing literature does not shed light on the frequencies transfer characteristics of such HF signals and there is a need to examine them, in order to meet the demands of present‐day UHVDC technologies [6, 7]. The second part of this paper proposes a WB model of the converter station and presents a comprehensive analysis of the transient frequency characteristics while they pass through the various parts of the converter station.…”

Determination of operating conditions of LCC for PCOV calculation based on detailed analysis of commutation overshoot

“…The accuracy of PCOV calculation can be greatly improved by time-domain numerical simulation adopting equipment models suitable for a wide frequency range, i.e. broadband models (or called as wideband models) [15][16][17][18], instead of low-frequency models used in analytical analysis. However, the application of broadband models significantly increases the scale of the electrical network to be solved and the solution step should be set at μs level.…”