Method for controlling compensated power network neutral point displacement voltage by grounding bidirectional offset-regulating switch

Abstract

The invention discloses a method for controlling compensated power network neutral point displacement voltage by a grounding bidirectional offset-regulating switch. The grounding bidirectional offset-regulating switch is arranged on a high-voltage winding of a grounding transformer, and two offset-regulating switches are generally arranged on two phases of A and C respectively. The bidirectional offset-regulating switch is characterized in that: the voltage is positively or reversely regulated according to the neutral point displacement voltage, so that the compensated power network neutral point displacement voltage is effectively controlled in a proper range, and the requirement on the sensitivity of arc extinguishing device measurement and automatic tracking is met. The positive voltage regulation is characterized by increasing the number of turns of high-voltage winding of the grounding transformer and increasing phase voltage; and the reverse voltage regulation is characterized by reducing the number of turns of high-voltage winding of the grounding transformer and reducing the phase voltage. The method can be applied to a distribution network compensated by arc extinguishing winding automatic tracking neutral point displacement voltage, is simple and practicable and economic and reliable, has stable performance, greatly improves the sensitivity of the automatic tracking compensation arc extinguishing device, reduces the threat of over-high neutral point displacement voltage on safe and reliable operation of the power network, and improves the reliability, safety and economical efficiency of the operation of the neutral point compensated power network through the arc extinguishing winding.

Description

technical field [0001] The invention relates to the field of distribution network for automatic tracking compensation of arc suppression coils, in particular to the invention of a method for controlling and compensating the displacement voltage of a neutral point of a power grid by a grounding-transformer bidirectional biasing switch. Background technique [0002] The arc suppression coil, especially the automatic tracking compensation arc suppression device, has been widely used in the distribution network. Reliability and improving the safe operation level of the power grid have played a greater role. However, due to some reasons on the network structure of the power grid, the structure of the arc suppression device and the operation mode, after the distribution network is compensated by the arc suppression device, the neutral point displacement voltage sometimes increases abnormally. Due to the abnormal increase of the neutral point displacement voltage of the compensati...

AI Technical Summary

Problems solved by technology

In some grid asymmetrical voltage U 0 Very small, some only a few volts, or even smaller, so that the automatic tracking and compensation arc suppression device cannot be measured and tracked. These problems existing on site are waiting to be resolved

[0026] 2) If the neutral point displacement voltage of the compensation grid is too high, it will affect the safe and stable operation of the grid

The analysis of the reason for the abnormal increase of the neutral point displacement voltage of the compensation grid is shown in formula (5), and some grid asymmetrical voltage U 0 It is too high, U N It is too high, so that the arc suppressing coil cannot be put into operation

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