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

1. OverviewMountain distribution networks are equipped with numerous small hydropower stations, most of which are run-of-river stations without regulation capacity. These stations are connected to the same line as electrical loads, bringing certain negative impacts on power grid operation. The most prominent issue among them is the voltage quality problem. During the wet season, small hydropower stations generate electricity to the grid, and the failure to achieve local power balance leads to el

1. IntroductionIn recent years, with the steady and rapid development of the national economy, electricity demand has grown significantly. In rural power grids, the continuous increase in load, combined with irrational distribution of local power sources and limited voltage regulation capabilities in the main grid, has resulted in a considerable number of 10 kV long feeders—particularly in remote mountainous areas or regions with weak grid structures—whose supply radius exceeds national standard

I. Analysis of the Principle of Power System Voltage RegulatorsBefore analyzing the principle of power system voltage regulators, it is necessary to analyze the excitation regulator and draw conclusions through comparison. In practical application, the excitation regulator uses voltage deviation as a feedback quantity for adjustment, thereby keeping the generator terminal voltage within the standard range. However, this type of voltage regulator, especially during grid faults, requires a large a

When evaluating power quality, voltage is a critical influencing factor. Voltage quality is typically assessed by measuring voltage deviation, fluctuation, waveform distortion, and three-phase symmetry—with voltage deviation being the most important indicator. To ensure high voltage quality, voltage regulation is generally required. Currently, the most widely used and effective method for voltage regulation involves adjusting the tap changer of power transformers.This paper primarily integrates

Long-Distance Power Line Distribution: Low Voltage and Large Voltage FluctuationsAccording to the "Technical Guidelines for Distribution Network Planning and Design" (Q/GDW 1738–2012), the supply radius of a 10 kV distribution line must meet the voltage quality requirements at the line’s end. In principle, the supply radius in rural areas should not exceed 15 km. However, in some rural regions, the actual supply radius may extend beyond 50 km due to low load density, small and widely dispersed e

Voltage is an important criterion in power quality testing. The quality of voltage determines whether the power system can operate safely and has a significant impact on the stability of the entire power grid system. Currently, voltage regulators are relatively common electrical equipment in power systems, capable of reasonably and scientifically controlling the entire process of high-voltage tests on electrical equipment, thereby continuously improving the feasibility of such tests.1. Requireme

Power voltage regulators are a major electrical equipment in distribution substations. Since the power supply capacity of most distribution substations is relatively small, the capacity of voltage regulators is generally below 1000 kV·A. Therefore, voltage regulators are transported to the site as complete units, with all accessories assembled at the factory before shipment. Hence, the installation work of power voltage regulators in distribution substations mainly includes transportation, visua

1. Fundamentals of Transformer Testing1.1 OverviewTransformers are among the most critical pieces of equipment for electric power transmission. Their quality and reliability directly affect the safe and dependable delivery of electricity. Damage to generator transformersor key substation transformers can disrupt power transmission, and repairing or transporting such large units often takes several months.During this downtime, power supply is compromised, adversely impacting industrial and agricu

First, the installation of 10 kV high-voltage disconnect switches must meet the following requirements. The first step is to select an appropriate installation location, typically near the switchgear power supply in the power system to facilitate operation and maintenance. At the same time, sufficient space must be ensured at the installation site to accommodate equipment placement and wiring.Secondly, equipment safety must be fully considered—for example, lightning protection and explosion-proo

1.IntroductionIn a double-busbar system, line energizing/de-energizing and bus transfer are fundamental switching operations. Under the double-busbar configuration, line protection voltage is derived from busbar potential transformers (PTs). The PTs are connected to the busbar via primary disconnect switches, with their secondary windings routed to the PT secondary terminal box. Each PT has three secondary windings: one for protection and measurement, one for metering, and one open-delta winding