Transformer impulse voltage

Transformer Impulse Voltage refers to the transient high voltage pulse suddenly applied to the transformer insulation system due to changes in weather conditions, lightning strikes, etc. in the power system. This pulse voltage has very high peak voltage and fast rise time characteristics, which may cause serious impact on the insulation system of the transformer.

There are two main sources of transformer impulse voltage:

External impacts: such as atmospheric discharge (such as lightning strikes) and transmission line faults, etc., cause high-energy voltage to act on the transformer instantaneously.

Internal shock: caused by the operation and faults of the transformer itself, such as ground faults, switching operations, etc., resulting in sudden voltage changes.

Transformer surge voltage may cause the following problems:

Insulation destruction: The peak voltage of the impulse voltage is extremely high, which may cause breakdown and destruction of the insulation layer, thereby causing equipment damage and even short-circuit failure.

Insulation aging: Under long-term high-voltage impact, insulation materials are prone to aging and deterioration, reducing the reliability and life of the insulation.

In order to prevent problems caused by transformer surge voltage, we can take the following measures:

Insulation design: Reasonably design the insulation structure and materials of the transformer to ensure that it can withstand the peak voltage caused by normal operation and surge voltage.

Insulation testing: Conduct insulation testing and insulation withstand voltage tests regularly to detect insulation aging and faults in a timely manner and take corresponding repair or replacement measures.

Grounding protection: Take good grounding devices and grounding protection measures to reduce the impact of impulse voltage on the transformer.

Lightning strike protection: Take reasonable lightning strike protection measures for the transformer to reduce the impact voltage of the lightning strike on the transformer.

At the same time, we should also strengthen the maintenance and management of transformers, regular inspections, and equipment updates and transformations to improve the reliability and resistance to impulse voltages of transformers to ensure the safe and stable operation of the power system.

Why do we need to shock the transformer?

Impulse testing of transformers is to verify whether the insulation system of the transformer can withstand the impulse voltage and to evaluate the reliability and performance of its insulation. This test is to ensure that the transformer can work properly in actual operation and has sufficient resistance to impulse voltage.

The purpose of impact power transmission is as follows:

Verify insulation strength: By applying high peak impulse voltage to the transformer, the voltage withstand performance of the insulation material and insulation system can be tested. This helps assess whether there are weaknesses, defects or damage to the insulation and determine whether it can withstand the surge voltages that may be encountered in actual operation.

Ensure safety and reliability: Impact power transmission can help discover potential insulation faults, aging or deterioration problems, and take timely repair or replacement measures to improve the safety and reliability of the transformer. Through regular impact power transmission testing, potential faults and accidents can be prevented and the stable operation of the power system can be ensured.

Provide performance evaluation: The impact power test can provide important data and indicators for the performance evaluation of the transformer. By analyzing the impulse voltage test results, it can be judged whether the insulation quality of the transformer meets the design requirements, further optimizing and improving the design and manufacturing process of the transformer, and improving product quality and performance.

Meet standard requirements: Impact power transmission is an important part of power equipment testing, which is usually carried out in compliance with national and international standards. By conducting impact power transmission tests on transformers, the requirements of relevant standards and specifications can be met to ensure the compliance and quality reliability of the equipment.

In short, the purpose of conducting impulse power transmission test on the transformer is to verify the reliability and endurance of its insulation system and ensure that the equipment can work safely and reliably in actual operation. This is an important quality control and product testing method in the power system, which helps to improve the quality of transformers and ensure the stable operation of the power system.

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