Transformer tap switch protection method based on built-in current and temperature sensor

Abstract

The invention discloses a transformer tap switch protection method based on built-in current and temperature sensors, and the method comprises the steps: installing the built-in current and temperature sensors in a main on-off contact MSV and a transition contact TTV of a transformer tap switch, and collecting the current and temperature of the main on-off contact and the transition contact; calculating the current of the main on-off contact and the transition contact to form an over-current quick-break criterion of the transformer tap switch; and calculating the temperature of the main on-off contact and the transition contact to form the temperature criterion of the tap switch of the transformer. And when the over-current quick-break criterion or the temperature criterion of the transformer tap switch is met, the transformer tap switch performs protection action, and acts on an alarm signal and a trip switch respectively according to the severity of the fault. According to the invention, slight faults of the transformer tap switch can be sensitively identified and rapid action can be realized.

Description

technical field [0001] The invention relates to the design of transformer protection in the field of power systems, in particular to a transformer tap changer protection method based on built-in current and temperature sensors. Background technique [0002] In modern large-scale power systems, transformers are widely used to increase or decrease voltage, and are the main electrical equipment in modern large-scale power systems. It is expensive to manufacture, and it will seriously affect the reliability of power supply after failure, and even threaten the safe and stable operation of the entire power system. The tap changer is the core component of the transformer to complete online voltage regulation; at the same time, it is also a fault-prone component of the transformer, especially the tap changer of the converter transformer. [0003] In engineering, transformers are usually equipped with electrical quantity protection and non-electrical quantity protection, which can r...

AI Technical Summary

Problems solved by technology

[0003] In engineering, transformers are usually equipped with electrical quantity protection and non-electrical quantity protection, which can reflect various internal short-circuit faults and grounding faults of the transformer; however, there are low sensitivity and poor quick action to short-circuit faults at the transformer tap changer. insufficient

In recent years, there have been many short-circuit faults of converter transformer tap changers. Due to the long operating time of the configured electric quantity protection and non-electric quantity protection, the converter transformer has been seriously damaged, and even exploded, causing more serious accidents.

The key reason is that there is no special current transformer and temperature sensor installed at the tap changer of the transformer, so that when a slight fault occurs at the tap changer, the traditional electrical quantity protection and non-electrical quantity protection cannot respond; The traditional electrical protection and non-electrical protection can only operate when the fault of the connecting switch develops further and spreads to the transformer body

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