Tambayar da Mafi Yawan Aiki na Busbar na Makarantun Kuliya da Kudaden Su

1. Hukumomin da Discharge na Busbar

1.1 Testi na Insulation Resistance

Testi na insulation resistance yana cikin hukumomin da ake amfani da shi a cikin hukumomin da ke gudanar da insulation electrical. Yana da kyau a matsayin yanayi da ya ba da insulation defects na through-type, absorption na moisture na dukkan, da kuma contamination na surface—wadannan adadin da suka haifar da ma ake kan resistance values. Amma, yana da kyau tsakanin wadanda suka biyo a lokacin da ake samun localized aging ko partial discharge faults.

Sunan da sauransu na insulation da abubuwan da ake bukata, common insulation resistance testers suna amfani da output voltages na 500 V, 1,000 V, 2,500 V, ko 5,000 V.

1.2 Testi na Power Frequency AC Withstand Voltage

Testi na AC withstand voltage yana taka high-voltage AC signal—mai karfi da rated voltage na equipment—to insulation zuwa rike (typically 1 minute idan ban da wani). Wannan testi yana iya samun local insulation defects da kuma bayyana ability na insulation don take da overvoltages a wurare na gudanar. Shi ne mai kyau da mai hakuri na insulation testi don in kafara failures na insulation.

Amma, shi ne testi mai kafara wanda zai iya sanya insulation defects da suka biyo da kuma karin degradation. Saboda haka, testi voltage levels yana da kyau a zama da GB 50150–2006 Code for Acceptance Test of Electric Equipment in Electrical Installation Projects. Standards na testi na porcelain da solid organic insulation suna nuna a Table 1.

Table 1: AC Withstand Voltage Standards for Porcelain and Solid Organic Insulation

Akwai hukumomi masu AC withstand voltage, including power frequency testing, series resonance, parallel resonance, da kuma series-parallel resonance. Don hukumomin da busbar discharge, standard power frequency AC withstand voltage testing yana da kyau. Test setup yana da kyau a zama based on the test voltage, capacity, da kuma available equipment, typically using a complete AC high-voltage test set.

1.3 Infrared Testing

Duk abubuwa masu temperature da ya fi absolute zero suna ci gaba infrared radiation. Amma da energy na infrared da wavelength distribution suna da alaka da temperature na surface. By measuring this radiation, infrared thermography can accurately determine surface temperature—forming the scientific basis of infrared temperature measurement.

From the perspective of infrared monitoring and diagnostics, high-voltage equipment faults can be broadly classified into two categories: external and internal. External faults occur on exposed parts and can be directly detected using infrared instruments. Internal faults, however, are hidden within solid insulation, oil, or enclosures and are difficult to detect directly due to blocking by insulating materials.

Infrared diagnosis of busbar discharge involves temperature measurement, calculation of relative temperature difference (accounting for ambient temperature), and comparison with normally operating busbars. This allows for intuitive identification of overheating and discharge locations.

2. Application of New Technologies

2.1 Ultraviolet (UV) Imaging Technology

When the local electric stress on energized equipment exceeds a critical threshold, air ionization occurs, leading to corona discharge. High-voltage equipment often experiences discharges due to poor design, manufacturing, installation, or maintenance. Depending on the electric field strength, this may result in corona, flashover, or arcing. During discharge, electrons in the air gain and release energy—emitting ultraviolet (UV) light when energy is released.

UV imaging technology detects this UV radiation, processes the signal, and overlays it onto a visible-light image displayed on a screen. This enables precise location and intensity assessment of corona, providing reliable data for evaluating equipment condition.

2.2 Ultrasonic Testing (UT)

Ultrasonic testing (UT) is a portable, non-destructive industrial inspection method. It enables fast, accurate, and non-invasive detection, localization, evaluation, and diagnosis of internal defects such as cracks, voids, porosity, and impurities—both in laboratories and field environments.

Ultrasonic waves are elastic waves that propagate through gases, liquids, and solids. They are categorized by frequency: infrasound (<20 Hz), audible sound (20–20,000 Hz), ultrasound (>20,000 Hz), and hypersonic waves. Ultrasound behaves similarly to light in terms of reflection and refraction.

As ultrasonic waves travel through a material, changes in acoustic properties and internal structure affect wave propagation. By analyzing these changes, ultrasonic testing assesses material properties and structural integrity. Common methods include through-transmission, pulse-echo, and tandem techniques.

Digital ultrasonic flaw detectors emit ultrasonic waves into the test object and analyze reflections, Doppler effects, or transmission to obtain internal information, which is then processed into images. This technology is highly effective for assessing the insulation condition of operating high-voltage busbars.

3. Specific Solutions for High-Voltage Busbar Discharge

If abnormal discharge in high-voltage busbars is not addressed promptly, it can lead to insulation overheating, eventual insulation failure, and even major blackouts. Therefore, discharge faults must be resolved quickly and prevented proactively.

3.1 Strict Commissioning and Acceptance Testing

Many busbar discharge faults stem from poor workmanship or lack of responsibility during construction. Test personnel must strictly follow codes and standards during acceptance testing of new equipment, identifying potential discharge risks early and correcting them before commissioning.

3.2 Replace Aging Busbar Insulators

Most operational busbar discharges are caused by aging of support insulators. A detailed inventory should be maintained, and insulators should be replaced based on service life to ensure adequate insulation strength.

3.3 Comprehensive Analysis Using Insulation and Diagnostic Tests

Insulation tests can effectively detect severe discharge faults. However, for early-stage or hidden discharges, advanced diagnostic methods such as infrared imaging, UV imaging, and ultrasonic testing are required for early detection and intervention. Therefore, a comprehensive analysis combining both insulation tests and diagnostic tests is essential to effectively prevent and mitigate busbar discharge failures.