A typical power station includes Generator Step-Up (GSU) transformers, Unit Auxiliary Transformers (UAT), Station Service Transformers, Excitation Transformers, and sometimes Start-Up/Black-Start transformers. Each handles different grid and plant loads.

The design process considers service voltage, system fault levels, loading profile, efficiency targets, noise limits, and lifecycle cost. Engineers choose core materials, insulation systems, winding configurations, and cooling types to meet performance goals while complying with standards. Mechanical design must withstand short-circuit forces and shipping stresses. Accessories like OLTCs, bushings, and monitoring devices are selected based on application. Environmental constraints, including footprint, transportation limits, and required environmental performance (leak containment, fire safety), also influence the final design.

Power transformers operate at transmission voltages and high kVA ratings, optimized for minimal losses at full load and long-distance transfer. Distribution transformers operate at lower voltages near end-users and are optimized for good efficiency over varying load levels. Power transformers typically serve substations between generation and transmission networks, while distribution transformers feed commercial or residential loads at utilization voltages.

By circulating regenerated oil through the transformer, contaminants embedded in the paper insulation can be dislodged and captured in the unit’s sorbent, improving the condition of both oil and solid insulation simultaneously.

LFD usually reduces total downtime, especially for large power transformers. Because heating is generated directly in the windings, the drying phase is much faster than in hot-air or oven methods for thick insulation. In many cases, drying time is shortened from weeks to several days, and there is no need to remove and transport the active part to an external oven. The trade-off is that setup and monitoring are more specialized, but overall outage time is typically significantly shorter and more predictable with LFD.

The service life of the filters in TOR-5 is not defined by calendar time alone, but mainly by the amount of moisture they actually adsorb and the number of regeneration cycles. In stable mid-life transformers, a single cartridge set can typically operate for several months before regeneration is required. With proper regeneration, the same zeolite can be reused many times, so the practical lifetime is often several years. What really limits life is oil contamination and mechanical degradation, not simple saturation.

Design starts with kVA demand, voltage class, cooling method, insulation, impedance, and thermal limits. Core cross-section, flux density, conductor size, winding arrangement, and cooling ducts are calculated to meet losses, temperature rise, and efficiency targets.

Image received. I can inspect the photo and point out any obvious issues affecting dielectric strength/breakdown voltage testing—I’ll look for the electrode geometry and gap (2.5 mm per IEC 60156/ASTM D877), electrode cleanliness and wear, signs of corona or pitting on leads, proper sample container and liquid level, presence of vacuum/degassing equipment, temperature control, HV cable routing and shielding, grounding and safety interlocks, and whether the unit appears to be a benchtop or portable field BDV tester (model identification and calibration sticker if visible).

If you want a focused check, send a close-up of the electrode region and the instrument panel/label. Tell me which standard you’re following and whether the sample was degassed before the photo; with that I’ll give specific, actionable feedback on test readiness and any immediate safety or repeatability concerns.

GlobeCore supplies replacement filters and cartridges for all CMM and UVR models. Please specify the filter dimensions or serial number, and we will provide compatible part details and pricing.

The TOR-100 tester measures breakdown voltage of transformer oil automatically according to IEC 60156. We will send a quotation including technical catalog, lead time, and certification details.