Binarîna Çantîn û Têkniyên Herêmî yên Birbajar a Insulasyonên Cih û Menuyan Serkeftin (RMUs)

Çavkantîna Di Navendê û Derveyê

Şirketê Toshiba Corporation ya Japoniya di salê 1999an de malbatên rezinê epoxy bêxeyan u tehnologîya caykardnayê çêdibû, u dema 2002an da serbest kirina birîka (RMU) bi izolyasyona pêkanî ya 24 kV. Li ber vê rengê, rêza malbatan parzûma xweşkiribû, u hûn ê ji bo dawiyên dertirîn ya 72 kV u 84 kV çalak dibin. Holec, ku destpêk di Ewropaya de wekî sernavkirê bi rûsnameyên dizaynê bêxeyan u procesên çêkirina nêmilafeta werdigirta, dema u dewam kir da alaka Eaton bû.

RMUyên bi izolyasyona pêkanî ya Holec yekan jî werdigirtandin di Çinê, u zeviyên birrêbî yên navendî yên din bikaranîn ra li ser projeyên Holec hatiye têkildar. Herewesereke Çin di vê parzan de destpêk dihewlê, lê çavkantina wê çabdar bû. Şirketan sernavkirên wekî Beijing Shuangjie, Shenyang Haocheng, u Beihai Galaxy malbatan çêdibûn ku testên modelê min bike, têneketina çêtirî çêdibû, u li ser virazana u operasyonan têkildar bûn.

Tehnolojîyên Sernavkir û Rewşa Çavkantîna

Biserta u parzûma tehnolojîyên izolyasyona pêkanî niha amadeyên serfiraziya u operasyonê ya RMUyên bi izolyasyona pêkanî ye. Malbatan zeviyên her duveji, an jî Toshiba u Hitachi, pir mîqdara insan, mal, u mîqdara parê çêdibûn ji bo tehnolojîyên izolyasyona pêkanî, u piştgiriya teknîkî çêdibû. Ber bi tevahî yên çavkantîna navendî yên dinya, tekmîlkir û rewşa çavkantîna niha:

• Çêkirina malbatên rezinê epoxy bêxeyan. Bi karîna malbatên rezinê epoxy bêxeyan bi karîna encapçulandina direktan interrupterên vakuumê, hewceyê hilberzêra digehortina calka u nehiyatiyê ya buffersên rubberê silicone.

• Dizaynê ya izolyasyonê bi tenêyî çêdibûnîya girtina u seviyên partial discharge.

• Zanîngeha u çêkirina procesên castingê ya rezinê epoxy bi tenêyî çêdibûnîyan partial discharge u çetkirina komponentên izolyasyona pêkanî.

• Zanîngeha u çêkirina layerên shielding surface bi komponentên izolyasyona pêkanî.

• Analîzê stability ê rejinekên epoxy. Bi karîna testên aging ê çêdibûnîyan qademe bi tenêyî studiya service life ê normal ê rejinekên epoxy u analîzê trend û rate ê guherandina performance, wekhevi partial discharge, ji dema service life.

• Dizaynê intelligent. Bi karîna teknolojîyên sensing u measurement ê bêxeyan bi tenêyî online monitoring ê qualitative u quantitative ê parametreên characteristic, wekhevi seviyên partial discharge.

Meseleyên Hemîn û Grenî

RMUyên bi izolyasyona pêkanî hewceyên teknîkî u process ê çêtirîn hene yên RMUyên bi izolyasyona SF₆ gas. Ji ber ku tehnolojîya were biçûk an procesên neyiş, riskê insulation failures, operational faults, u potential hazards zêdetir in yên RMUyên bi izolyasyona SF₆ gas. Buna, RMUyên bi izolyasyona pêkanî hewceyên standardên çêtirîn ê teknîkî, processên manufacturing, u quality ê raw material. Ji ber ku bi pelanê user ê acceptance ê çêdibû, meseleyên parzûman ji nîşeya long-term industrial development u equipment reliability:

(1) Meseleyên Partial Discharge

Ji gas insulation, ku gas leakage dikare bi monitor bikin u discharges dikare bi self-recover, solid insulation, herî ku damaged by discharge, neyên dikare bi recover. Discharges tend to grow over the product's lifetime, potentially leading to insulation breakdown and phase-to-phase short circuits.

(2) Cracking ê Komponentên Izolyasyon

RMUyên bi izolyasyona pêkanîya hêsan, hemî di navendê de hemî di derveyê de, hate destpêk çetkirina komponentên izolyasyon ji ber vibrationên power frequency ê long-term, vibrationên operational, mechanical impacts, thermal cycling, u environmental temperature fluctuations, ku hate zêdetir accident rates.

(3) Safety u Reliability ê Isolation Function

Safety u reliability ê isolation function di RMUyên bi izolyasyona pêkanî de sernavkir e. Niha, disconnect switches ê three-position traditional ê bikar îndek, fully encapsulated within the solid insulation. The insulation performance of the isolation break depends on both the air gap between moving and stationary contacts and the surface creepage distance of the insulating component. Surface flashover along the insulating component increases the risk of break failure and potential personnel hazards. Additionally, environmental factors and material aging can increase surface leakage currents, significantly reducing insulation performance and threatening safe and reliable operation.

(4) Material Selection u Development ê Insulation

Quality u performance ê primary insulation materials directly affect the reliability and stability of the entire unit. Given the extensive use of insulation materials, considerations for recycling, separating, treating, and reusing scrap materials and components are essential to minimize resource waste.

(5) Encapsulation Process Issues

Product design should facilitate ease of manufacturing and assembly, while the manufacturing and assembly processes should aim for minimal or no environmental pollution and optimal use of energy and resources. For encapsulated products, the formulation of the encapsulation process and selection of encapsulation equipment are particularly critical.

Key Technology Analysis

(1) High-Quality, High-Efficiency Encapsulation Technology

Based on the mechanism of partial discharge, internal discharges in solid insulation components are primarily caused by voids (bubbles) within the material. Conventional encapsulation involves placing preheated components into a preheated metal mold, evacuating the mold cavity, slowly injecting heated, curable epoxy resin, and curing. This method is inefficient, costly, and often fails to completely eliminate bubbles, leading to numerous voids. These voids can cause partial discharge after commissioning, eventually resulting in insulation breakdown and compromising safe and reliable operation. Therefore, adopting advanced, high-quality, and efficient epoxy resin encapsulation technology is essential.

(2) Optimization of Insulation Module Structure Design

Insulation module design must meet functional, inspection, and installation requirements while also ensuring aesthetic appeal, reduced material consumption, and avoidance of residual stress. Residual stress can cause internal and external cracks in insulation components, which may lead to partial discharge and eventual insulation breakdown during operation. Thus, in-depth research on the overall layout, thickness, and transitions of insulation modules is necessary, along with consideration of heat dissipation design.

(3) Optimization of Electric Field Design

Corona discharge occurs when the electric field strength near a conductor's surface reaches the breakdown strength of the surrounding gas, typically in highly non-uniform fields. Sharp edges or points on high-voltage electrodes may concentrate the electric field, causing corona discharge. As a form of partial discharge, corona can progress to insulation breakdown over time, affecting safe and reliable operation. Therefore, designing conductive components to ensure a sufficiently weak and uniform electric field is a key technology. Effective methods include using simulation software for electric field calculations, optimizing the distribution of electric fields, and refining insulation and electrode shapes. Shielding rings or similar measures to reduce electric field strength may also be necessary.

(4) Research and Design of Shielding Layers

The primary purposes of applying a grounded metal shielding layer on the outer surface of insulation modules are: first, to confine short-circuit faults to phase-to-ground only in the event of insulation failure, reducing internal arcing energy and fault risk; second, to maintain insulation performance in any environment without requiring surface cleaning, achieving maintenance-free operation, and ensuring unchanged electric field distribution even if metallic foreign objects enter the enclosure.

(5) Research and Analysis of Epoxy Resin Stability

As a polymer material, epoxy resin can degrade (age) during processing, application, and storage, affecting its performance and service life. The most common aging factors are heat and ultraviolet radiation. In switchgear, continuous heat generation during operation inevitably accelerates the aging of epoxy resin. Therefore, using simulated aging tests to statistically analyze the performance of solid insulation components made from different materials and at various aging stages is essential to establish critical relationships.

Conclusion

Solid insulation technology has gained recognition from users and the market and is being increasingly promoted and deployed. This requires equipment manufacturers to produce products that meet the demands of power supply reliability and stability. Significant research has been conducted on encapsulation processes and surface shielding layer design for solid-insulated RMUs, yielding tangible results. However, these efforts are still insufficient. Greater emphasis must be placed on research into new encapsulation materials, prevention of insulation component cracking, and innovative component structural designs. In summary, further technical research, accumulation, and breakthroughs are needed for solid-insulated RMUs.