Neutral point and high damping resistor

Abstract

The invention belongs to the field of power systems and enterprise power supply systems, and in particular discloses a neutral point and high damping resistor. A high damping resistor is connected inseries to the neutral point and the ground of a primary side or a secondary side of a transformer, and is then grounded through a current transformer. The high damping resistor has a resistance changeno more than +-2% at high temperature, and is also provided with a current meter and a thermometer, and the like. In case of high temperature, the resistance change is small and does not exceed +-2%.If the damping range is expanded, the high damping resistor is suitable if the ratio between capacitance current IR and IC that reaches 1:6 which is much greater than 1:1. The high damping resistor can be widely applicable to capacitance current of a unit voltage class system, better and effectively protects unit voltage class systems at large, can improve continuity and reliability of power supply of most of the systems, can lower incidence rate, increases power supply reliability, and greatly reduces economic loss. The high damping resistor can effectively suppress high frequency electric arc restrike overvoltage, can resist high temperature, obviates the need for expanding the space for heat dissipation, has a small size, and can save material cost.

Description

technical field [0001] The invention belongs to the field of power systems and enterprise power supply systems, namely neutral point high damping resistors. Background technique [0002] Whether the power system and enterprise power supply system can achieve safe operation and reduce accidents is closely related to the neutral point grounding method of each voltage level system. Different neutral point grounding methods have completely different effects on safe operation. [0003] Summarize the advantages and disadvantages of the ungrounded neutral point of the power grid, from the perspective of power supply continuity, reliability, single-phase grounding sustainable operating time, suppression effect on resonance, fault point burning degree, high frequency arc restrike and power frequency arc restrike Comparing the suppression level of overvoltage, the impact on relay protection, personal safety, and the overall accident rate, etc., the existing high-resistance grounding t...

AI Technical Summary

Problems solved by technology

Fearing that the resistivity will change due to the temperature rise of the resistor when the single-phase is grounded, which will affect the damping resonance effect and prevent the resistor and other accessories from being burned out at high temperature, it is forced to artificially increase the volume of the device, increase the heat dissipation space and occupy an area However, even so limited to the performance factor of the resistor sheet material, there is still the problem of resistivity out of tolerance, which will eventually affect the damping resonance effect and reduce the scope of application.

In addition, in the manufacture of the shell, the volume is large and the cost is high

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