IntroductionElectric transformers are the backbone of modern power distribution systems, silently enabling the reliable delivery of electricity to homes, businesses, and industries. As these critical assets age and the demand for uninterrupted power grows, the importance of diligent transformer maintenance has never been greater. This essay explores the essential role of transformer maintenance, highlighting the value of proactive care, the impact of advanced diagnostic technologies, and the tra

Transformer Operation PrincipleA transformer is an electrical device that operates on the principle of electromagnetic induction to transfer electrical energy from one circuit to another. It enables the adjustment of voltage levels within an alternating current (AC) system, either stepping up (increasing) or stepping down (decreasing) voltage while maintaining the same frequency.Working Principle:Basic ComponentsA transformer consists of two coils, known as windings—the "primary winding" connect

1. Definition of High-Voltage Cable Line Constant TestingHigh-voltage cable line constant testing refers to the systematic measurement, using specialized instruments, of electrical parameters such as resistance, inductance, capacitance, and conductance before a cable line is commissioned or after major maintenance. The aim is to obtain fundamental data characterizing the electromagnetic properties of the cable, serving as a critical testing phase that provides accurate parameter support for powe

1.Work Environment Requirements and Safeguard MeasuresBased on technical requirements for cable equipment storage, laying, transportation, laying, transposition, testing, and cable terminations, the project owner and construction units have conducted extensive trials and implemented protective measures regarding ambient temperature, humidity, bending radius, traction control, and route optimization. These measures ensure high-voltage cable quality and on-site safety under harsh winter conditions

Withstand voltage test is an insulation test, but it is a destructive test that can reveal insulation defects difficult to detect in non-destructive testing.The test cycle for high-voltage cables is three years, and it must be conducted after non-destructive tests. In other words, the withstand voltage test is performed only after all non-destructive tests have been passed.Most high-voltage cables used today are cross-linked polyethylene (XLPE) cables, which can have large cross-sections and cov

I. Introduction to Cable Grounding Loop CurrentCables rated 110 kV and above use a single-core structure. The alternating magnetic field generated by the operating current induces a voltage on the metallic sheath. If the sheath forms a closed circuit through the earth, a grounding loop current will flow on the metallic sheath. Excessive grounding loop current (loop current exceeding 50 A, more than 20% of the load current, or a ratio of maximum-to-minimum phase current greater than 3) not only a