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

High- and Low-Voltage Cable Lines and Cable Trays Inspect cable trays for proper closure and secure rodent-proof sealing. High- and low-voltage cable trays should be intact and undamaged. Address any abnormalities promptly and maintain records. Check for water seepage in cable trays entering switchrooms located in basements or low-lying areas. Inspect cable pits and trenches for standing water or debris, and promptly drain water and remove contaminants if found. Cables and cable terminations wit

I. Allowable TemperatureWhen a transformer is in operation, its windings and iron core generate copper loss and iron loss. These losses are converted into heat energy, causing the temperature of the transformer's iron core and windings to rise. If the temperature exceeds the allowable value for a long time, the insulation will gradually lose its mechanical elasticity and age.The temperature of each part of the transformer during operation is different: the winding temperature is the highest, fol

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

Traction Rectifier TransformersRated capacity: 800 to 4400 kVA; Voltage class: 10 kV and 35 kV; Rectifier pulse number: 12-pulse and 24-pulse. Compared with 12-pulse rectifier circuits, 24-pulse rectifier circuits can reduce the harmonic pollution of the power grid by 50%, and no filtering equipment is needed at this location. It is suitable for power supply systems of urban subways and rail transit.Excitation Rectifier TransformersRated capacity: 315 to 3000 × 3 kVA; Voltage class: 10 kV, 13.8

This report is based on the analysis of one-day power quality monitoring data of your company's distribution system. The data shows that there is significant three-phase current harmonic distortion in the system (with a high total harmonic distortion of current, THDi). In accordance with international standards (IEC/IEEE), harmonic currents at this level have posed substantial risks to the safe, reliable, and economical operation of the power supply transformer, mainly manifested in additional h

Compared with 12kV, 24kV can supply more electrical energy, reduce line losses, and is widely used in overseas markets.SF₆ is a greenhouse gas whose ozone layer depletion potential is over 20,000 times that of CO₂. Its use must be restricted; therefore, medium-voltage switchgear must not use SF₆ as an insulating gas.For switchgear, environmentally friendly gases refer to those that do not contain SF₆ as insulating or arc-extinguishing media. Examples include naturally occurring gases (such as ni

1. R&D of New Materials and Equipment & Asset Management1.1 R&D of New Materials and New ComponentsVarious new materials serve as the direct carriers for energy conversion, power transmission, and operation control in new-type power distribution and consumption systems, directly determining operational efficiency, safety, reliability, and system costs. For instance: New conductive materials can reduce energy consumption, addressing issues such as energy shortage and environmental pol

1 Overview of Power Transmission and Distribution Lines1.1 Key Characteristics of Power Transmission and Distribution Lines High Maintenance Difficulty: This is mainly due to the wide area covered by power transmission and distribution lines, the harsh terrain of the laying areas, and the impact of seasonal climate changes, all of which contribute to difficult maintenance. High Requirement for Operational Reliability: The reliable operation of power transmission and distribution lines is closely

I. What is a Grid Voltage Overvoltage Fault?Grid voltage overvoltage refers to a phenomenon in power systems or circuits where the voltage exceeds the normal operating range.Generally, under power frequency, if the RMS (Root Mean Square) value of the AC voltage rises to more than 10% above the rated value and lasts for more than 1 minute, it can be determined as a grid voltage overvoltage fault.For example, in China’s common 380V three-phase grid system, if the voltage exceeds 418V and persists

Transformers are the "unsung heroes" of the modern world. These seemingly unremarkable devices, either hidden on utility poles or installed in substations, play an indispensable role in the power grid system—it is through them that electrical energy can be efficiently converted, transmitted, and utilized. Today, as humanity stands at the crossroads of an accelerating transformation in the energy landscape, recognizing the transformative potential of transformers and exploring how they will shape