Heavy-Duty Package Substation for Mining & Solar Sites

A:The load rate has consistently exceeded 80% and there have been frequent overloads; the losses under no-load and at full load are more than 20% above the standard; insulation has aged (with excessive dielectric loss values and deteriorated oil quality); serious faults have occurred (such as winding deformation and multiple-point grounding of the core); the energy efficiency grade is lower than level 3 and energy-saving renovations are not economically viable; it has reached the design service life (generally 20–30 years).