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

1 Characteristics and Components of High-Voltage Transmission Lines1.1 Characteristics of High-Voltage Transmission LinesHigh-voltage transmission lines are characterized by their relatively low cost due to the smaller amount of information they require. They typically use two conductors, one connected to the positive pole and the other to the negative pole. DC transmission lines have durability and can transmit current over long distances. In some high-voltage transmission facilities in China,

Since the second half of the 19th century, the only insulating materials suitable for high-voltage power transmission lines were ceramics and glass. Starting in the 1940s, with the emergence of polymer materials, ceramics and glass were no longer the preferred choices, prompting countries in Europe and America to begin researching polymer insulators. Subsequently, extensive studies were conducted on the physical properties, electrical characteristics, long-term reliability, and optimal shapes of

Thermal power remains vital in the global energy mix, yet traditional systems face challenges of high energy consumption and emissions, requiring innovation for greener operations. High-voltage inverters, by regulating motor speed, offer an effective solution for energy efficiency and emission reduction in power plants.1 Overview of High-Voltage InvertersHigh-voltage inverters control high-voltage motors and transformers by adjusting frequency, enabling energy savings, improved efficiency, and e

1 Basic Structure and Operating Mechanism of High-Voltage Inverters1.1 Module CompositionRectifier Module: This module converts the input high-voltage AC power into DC power. The rectification section mainly consists of thyristors, diodes, or other power semiconductor devices to achieve the conversion from AC to DC. Additionally, through a control unit, voltage regulation and power compensation within a certain range can be realized.DC Filter Module: The rectified DC power is processed by a filt

As the demand for precise control in industrial processes continues to rise, traditional Pulse-Width Modulation (PWM) technology struggles to meet the requirements for high dynamic performance and low harmonic distortion. In contrast, high-frequency PWM technology enhances output waveform quality and reduces system harmonics by increasing the carrier frequency, thereby optimizing the performance of inverters. Consequently, balancing system efficiency and reliability when applying high-frequency

1 Characteristics of Nitrogen-Insulated Ring Main UnitsThe new generation of nitrogen-insulated ring main units has the following main characteristics: Excellent insulation performance. All live components are sealed inside, with external surfaces made of insulating material, effectively blocking current flow and preventing interference from external charged objects. Strong resistance to external environmental conditions. Both the enclosure and internal insulation materials possess high resilien

1. Air-insulated and SF₆ Gas-insulated Ring Main UnitsAir-insulated ring main units primarily integrate load break switches, disconnectors, or a combination of both with grounding capabilities, operated either manually or electrically. These units may also incorporate fuses to control cable input and output lines. Conversely, SF₆ gas-insulated ring main units, commonly referred to as gas-insulated switchgear, utilize SF₆ gas for insulation and arc quenching due to its high dielectric strength, p

Development Status at Home and AbroadToshiba Corporation of Japan developed high-performance epoxy resin materials and casting technology in 1999, and subsequently launched a 24 kV solid-insulated ring main unit (RMU) in 2002. The product line has since been expanded, and the company is now advancing toward higher voltage levels of 72 kV and 84 kV. Holec, originally a European pioneer with advanced design concepts and environmentally friendly manufacturing processes that produce no pollution, wa

1.Current Application Status of Solid-Insulated Ring Main Units in Medium-Voltage Distribution Networks1.1 Widespread Application in Urban Residential AreasThe core components of medium-voltage ring main units (RMUs) primarily consist of load switches and fuses. These units offer several advantages, including a simple structure, compact size, and relatively low cost. Additionally, they effectively improve power quality and enhance the reliability and safety of power supply. Observations indicate

Current Application Status of Solid-Insulated Ring Main Units in Medium-Voltage Distribution Networks(1) Solid-insulated ring main units (RMUs) have been widely applied in urban residential areas and other medium-voltage distribution applications. The core components of medium-voltage RMUs mainly include the load switch and the fuse. These units offer advantages such as a simple structure, compact size, and low cost, while effectively improving power supply parameters and enhancing operational s