National-strategic investment in European power transmission capacity

With series compensation of the line reactance, the problem of its protection against overcurrents arises regarding relay protection. The greater the degree of compensation, the greater the problem. When compensating for more than 50% of the reactance of the line, the protection of power transmission lines becomes practically impossible due to the failure or false operation of all existing kinds and types of protection [1, 2]. Therefore, as for now, the compensation of the line reactance usually is no more than 50% [3, 4], which does not allow to reveal the full potential of the line in terms of its transmission capacity. The goal of this research was to study the processes occurring in emergency modes on power lines equipped with a series capacitor bank, the understanding of which would help to produce algorithms that can protect power lines with SCB with a degree of the longitudinal resistance compensation of the line of more than 50%.

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Use of a phase-shifting transformer for increasing the power transmission capacity, taking into account the mode of the adjacent network

Proceedings of Irkutsk State Technical University ◽

10.21285/1814-3520-2021-3-369-379 ◽

2021 ◽

Vol 25 (3) ◽

pp. 369-379

Author(s):

V. P. Shoiko ◽

K. V. Dukhanina

Keyword(s):

Power Systems ◽

Cross Section ◽

Software Package ◽

Power Transmission ◽

Phase Shifting ◽

Transmission Capacity ◽

Automatic Equipment ◽

Thyristor Switch ◽

Determining Factor ◽

Engineering Institute

In this research, we develop measures aimed at improving the efficiency of power systems by increasing their transmission capacity. To this end, a FACTS system based on the phase-shifting transformer with a thyristor switch developed at the Power Engineering Institute named after G.M. Krzhizhanovsky was used. The efficiency of the phaseshifting transformer under study for increasing the transmission capacity of power systems was determined by the maximum permissible cross-section flows of the Barnaul-Biysk node-2. The calculations were performed for normal and various post-accident schemes using the RastrWin3 software package. Such factors as the regulation of the taps of the phase-shifting transformer and various places of its installation were considered. For the section under consideration, the phase-shifting transformer increased the maximum permissible flow by 4–12%. The determining factor limiting the maximum permissible flow in the Barnaul-Biysk node-2 was found to be the current overload of the 110 kV lines of the adjacent network. The greatest effect of increasing the maximum permissible overflow was noted when the phase-shifting transformer was installed on the 220 kV line adjacent to the section, parallel to the 110 kV lines (which were overloaded when the mode became heavier), rather than on the 220 kV line included in the section. Similar calculations were performed for normal and post-accident schemes of an alternative option, which involved replacing wires and installing automatic equipment for limiting equipment overload on overloaded 110 kV lines. The obtained results show that the effect of increasing the transmission capacity for this option comprised 4%.

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