Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

1. Definition of Condition-Based MaintenanceCondition-based maintenance refers to a maintenance method where decisions on whether and how to perform maintenance are determined based on the real-time operating status and health condition of equipment. It has no fixed maintenance methods or schedules. The prerequisite for condition-based maintenance is the establishment of equipment parameters and the comprehensive analysis of various operational information of the equipment, so as to make reasona

In the reconstruction and expansion of modern urban power grids, to optimize the power supply layout, it is required that high - voltage directly enters urban areas, medium - voltage penetrates deep into load centers to shorten the low - voltage power supply radius, and underground cable laying is mostly adopted for urban main roads. Electrical equipment needs to meet the requirements of intelligence, miniaturization, high reliability and aesthetics. The compact substation is widely used in urba

Global energy transition boosts offshore wind power, yet complex marine environments challenge turbine reliability. The heat - dissipation of pad - mounted transformer control cabinets (PMTCCs) is critical—undissipated heat causes component damage. Optimizing PMTCC heat dissipation improves turbine efficiency, but research mostly focuses on onshore wind farms, neglecting offshore ones. Thus, design PMTCCs for offshore conditions to enhance safety.1 PMTCC Heat - Dissipation Optimization

I. Design Principles of Pad-mounted TransformersWith the upgrading of power infrastructure, pad-mounted transformers are widely used in various scenarios due to their light weight, small size, low loss, low noise and high reliability. Studies show that when the power supply voltage is increased from 380V to 10kV, line loss is reduced by 60%, and copper consumption and investment are each reduced by 52%, with remarkable economic and social benefits. As a product of modern economic and social deve

Winding Resistance Test DefinitionThe winding resistance test of a transformer checks the health of transformer windings and connections by measuring resistance.Procedure of Transformer Winding Resistance MeasurementFor star connected winding, the resistance shall be measured between the line and neutral terminal.For star connected autotransformers the resistance of the HV side is measured between HV terminal and IV terminal, then between IV terminal and the neutral.For delta connected windings,

Temperature Rise Test DefinitionA temperature rise test of a transformer checks if the temperature increase of its winding and oil meets specified limits.Temperature Rise Test for Top Oil of Transformer First, the LV winding of the transformer is short-circuited. Then one thermometer is placed in a pocket in the transformer top cover. Other two thermometers are placed at the inlet and outlet of the cooler bank respectively. The voltage of such value is applied to the HV winding that power input

Dielectric Test DefinitionThe dielectric test of a transformer checks the insulation’s ability to handle voltage without breaking down.Separate Source Voltage Withstand Test of TransformerThis dielectric test checks the main insulation’s ability to withstand voltage between the winding and the earth.Procedure All three line terminals of the winding to be tested are connected together. Other winding terminals not under test and the transformer tank should be connected to the earth. Then a single-

Vector Group Test DefinitionThe vector group test of a transformer checks the phase sequence and angular difference to ensure transformers can operate in parallel.Vector Group Test of TransformerThe vector group of a transformer is essential for successful parallel operation of transformers. Every electrical power transformer must undergo a vector group test at the factory to ensure it matches the customer’s specified vector group.The phase sequence, or the order in which phases reach their peak

Transformer DefinitionA transformer is defined as an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction.Theory of Transformer on No-LoadHaving No Winding Resistance and No Leakage ReactanceConsider a transformer with only core losses, meaning it has no copper loss or leakage reactance of transformer. When an alternating current source is applied to the primary, it supplies current to magnetize the core of transformer.But this current

Losses in TransformerAs the electrical transformer is a static device, mechanical loss in transformer normally does not come into picture. We generally consider only electrical losses in transformer.Loss in any machine is broadly defined as difference between input power and output power. When input power is supplied to the primary of transformer, some portion of that power is used to compensate core losses in transformer i.e. Hysteresis loss in transformer and Eddy current loss in transformer c