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

1 Insulation Materials and DesignBased on cost statistics for medium-voltage solid-insulated ring main units (RMUs), the insulation structure accounts for over 40% of the total cost. Therefore, selecting appropriate insulation materials, designing rational insulation structures, and determining the correct insulation method are crucial to the value of medium-voltage RMUs. Since the first synthesis of epoxy resin in 1930, various additives have been continuously explored to improve its properties

1 Live Testing AnalysisDetection of Issues through Live TestingIn October of a certain year, during live partial discharge (PD) testing on 10kV ring main units (RMUs) under our jurisdiction, the maintenance and testing team observed significantly elevated signal amplitudes in several units (Transient Earth Voltage (TEV) readings around 18 dB, and ultrasonic readings around 20 dB). Most of these units were from the same manufacturer. Consequently, a unified test was conducted on 15 RMUs from this

A HKSSPZ-6300/110 electric arc furnace transformer has the following basic parameters:Rated capacity S = 6300 kVA, primary voltage U₁ = 110 kV, secondary voltage U₂ = 110–160 V, vector group YNd11, with both low-voltage winding ends (start and finish) brought out, and equipped with 13-step on-load tap changing. Insulation levels: HV/HV neutral/LV, LI480AC200 / LI325AC140 / AC5.The transformer uses a dual-core series voltage regulation design, with an "8"-shaped low-voltage winding conf

Performance Degradation Characteristics and Life Prediction of Power Capacitors under High-Temperature ConditionsWith the continuous expansion of power systems and increasing load demands, the operating environment for electrical equipment has become increasingly complex. Rising ambient temperature has emerged as a key factor affecting the reliable operation of power capacitors. As critical components in power transmission and distribution systems, the performance degradation of power capacitors

1. Overview of Surge Arrester Handover Test Technology1.1 Necessity of Handover TestThe handover test is a crucial step in ensuring the performance and safe operation of surge arresters within power systems. For power systems with voltage levels at 220 kV and below, surge arresters play a core role in protecting electrical equipment from damage caused by overvoltages and lightning strikes. However, during the process from the arrester leaving the factory to its actual operation after installatio

1 Architecture of the Online Monitoring System for Zinc Oxide Surge ArrestersThe online monitoring system for zinc oxide surge arresters comprises three layers: the station control layer, bay layer, and process layer. Station Control Layer: Includes a monitoring center, a Global Positioning System (GPS) clock, and a B - code clock source. Bay Layer: Consists of online monitoring Intelligent Electronic Devices (IEDs). Process Layer: Features monitoring terminals for Potential Transformers (PTs) a

A core challenge in online cable eccentricity measurement is the cable’s high - speed motion. This requires non - contact measurement equipment that can handle cable jitter. X - ray cable eccentricimeters, based on optical transmission imaging, measure multi - layer contour dimensions to calculate the geometric center of conductors relative to insulation eccentricity. However, they have drawbacks: slow measurement speed (only a few times per second), increased errors from cable jitter,

The integrated wiring system of intelligent buildings, as the core carrier of information transmission, functions like a "nervous system." It connects signals such as voice, data, and images, enabling device interconnection and efficient information transmission. Cable detection is a key link to ensure system performance and information security, focusing on index detection, problem troubleshooting, and response measures.1. Core Cable Detection Indicators1.1 Appearance and Identification Verific

1 Error Analysis of Traditional Turn Ratio Testing MethodsThe QJ35 turn ratio bridge and other single-phase-phase-based testers all use the double-voltmeter principle. The QJ35, however, eliminates power supply fluctuation interference via bridge balance. For three-phase transformer ratio testing with a single power supply, corresponding terminals must be shorted and data converted, turning three-phase tests into independent single-phase measurements, with √3 Yd conversion based on con

1 Investigation of Insulation Defects in UHV Oil - immersed ReactorsKey challenges in high - voltage oil - filled reactors during operation include insulation faults, iron - core magnetic leakage heating, vibration/noise, and oil leakage.1.1 Insulation FaultsParallel - connected reactors, once connected to the main grid’s primary coil and put into use, operate at full power long - term. Sustained high voltage raises operating temperatures, accelerating aging of coil insulation material