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

Voltage Compliance Rate and Distribution Transformer Tap Changer AdjustmentThe voltage compliance rate is one of the main indicators for measuring power quality. However, due to various reasons, electricity consumption during peak and off-peak periods often differs significantly, causing the output voltage of distribution transformers to fluctuate. These voltage fluctuations adversely affect the performance, production efficiency, and product quality of various electrical equipment to varying de

1. Structure Forms and Classification of BushingsThe structure forms and classification of bushings are shown in the table below: Serial No. Classification Feature Category 1 Main insulation structure Capacitive Type Resin-impregnated paperOil-impregnated paper Non-capacitive Type Gas insulationLiquid insulationCasting resinComposite insulation 2 External Insulation Material PorcelainSilicone Rubber 3 Filling Material Between Capacitor Core and Exte

On May 7, China's first large-scale integrated wind-solar-thermal-storage comprehensive energy base UHV transmission project—the Longdong~Shandong ±800kV UHV DC transmission project—was officially energized and put into operation. The project has an annual transmission capacity exceeding 36 billion kilowatt-hours, with new energy sources accounting for more than 50% of the total. After commissioning, it will reduce carbon dioxide emissions by approximately 14.9 million tons annually, contributin

(1) The contact gap is primarily determined by insulation coordination parameters, interruption parameters, contact material of the high-voltage SF₆-free ring main unit, and the design of the magnetic blowout chamber. In practical application, a larger contact gap is not necessarily better; instead, the contact gap should be adjusted as close as possible to its lower limit to reduce operating energy consumption and extend service life.(2) The determination of contact overtravel is related to fac

Low-voltage distribution lines refer to the circuits that, through a distribution transformer, step down the high voltage of 10 kV to the 380/220 V level—i.e., the low-voltage lines running from the substation to the end-use equipment.Low-voltage distribution lines should be considered during the design phase of substation wiring configurations. In factories, for workshops with relatively high power demand, dedicated workshop substations are often installed, where transformers supply power direc

The Impact of Voltage Harmonics on Temperature Rise in H59 Distribution TransformersH59 distribution transformers are among the most critical equipment in power systems, primarily functioning to convert high-voltage electricity from the power grid into low-voltage electricity required by end users. However, power systems contain numerous nonlinear loads and sources, which introduce voltage harmonics that adversely affect the operation of H59 distribution transformers. This article will discuss i

1. OverloadFirst, with the improvement of people's living standards, electricity consumption has generally increased rapidly. The original H59 distribution transformers have small capacity—“a small horse pulling a big cart”—and cannot meet user demands, causing the transformers to operate under overload conditions. Second, seasonal variations and extreme weather conditions lead to peak electricity demand, further causing H59 distribution transformers to run overloaded.Due to long-term overload o

In power systems, transformers, as core equipment, are critical to the safe operation of the entire grid. However, due to various reasons, transformers are often exposed to multiple threats. In such cases, the importance of grounding resistor cabinets becomes evident, as they provide indispensable protection for transformers.Firstly, grounding resistor cabinets can effectively protect transformers from lightning strikes. The instantaneous high voltage caused by lightning can severely damage tran

Recently, the NSR-3611 low-voltage protection and control device and the NSD500M high-voltage measurement and control device—both developed by a Chinese protection and control equipment manufacturer—successfully passed the IEC 61850 Ed2.1 Server Level-A certification test conducted by DNV (Det Norske Veritas). The devices have been awarded the international Level-A certification by the Utilities Communication Architecture International Users Group (UCAIug). This milestone marks the manufacturer

1.Linear Regulators vs. Switching RegulatorsA linear regulator requires an input voltage higher than its output voltage. It handles the difference between input and output voltages—known as the dropout voltage—by varying the impedance of its internal regulating element (such as a transistor).Think of a linear regulator as a precise “voltage control expert.” When faced with excessive input voltage, it decisively “acts” by “cutting off” the portion exceeding the desired output level, ensuring the