1. IntroductionCurrently, with the rapid development of the economy and science and technology, and the increasing intelligence of the informatization level, the construction of substations is also becoming more and more intelligent. Among them, cable tunnels are an important means for substations to achieve intelligence. Therefore, in practical applications, higher technical and quality requirements are needed. For example, to meet the needs of complex signal transmission, the cable tunnels in

1. Container Scheme1.1 Structural SchemeIn the container structural scheme, the container is mainly constructed from steel plates, steel beams, steel columns, corner fittings, etc. The container structure is an integrated structure formed by combining steel plates and a frame. Based on the single - layer layout of the container, finite - element software is used to establish the container structure model, and then the building load of the container structure is simulated and calculated. The calc

Feeder ProtectionDefinitionFeeder protection refers to safeguarding electrical feeders against faults to ensure the uninterrupted power supply of the grid. Feeders transmit electrical energy from substations to the load end. Given their crucial role in the power distribution network, protecting feeders from various types of faults is of utmost importance. The primary requirements for feeder protection are as follows: Selective Tripping: During a short - circuit event, only the circuit breaker cl

An important consideration for a generator circuit breaker is its current - carrying capacity. The rated currents of generators typically span from 3000 A (for 50 MVA units) to 50000 A (for 2000 MVA units). As these currents flow through the circuit breaker, heat is generated. To increase the rated current of a specific circuit breaker, it is essential to enhance the heat transfer to the surrounding environment, ensuring that the temperatures of all components remain within acceptable limits.Con

Generator Differential ProtectionDifferential protection for a generator primarily safeguards the stator windings against earth faults and phase - to - phase faults. Stator winding faults pose a significant threat, capable of inflicting severe damage on the generator. To protect the stator windings, a differential protection system is utilized to clear faults in the shortest time possible, thereby minimizing the extent of damage.Merz - Prize Circulating Current SystemIn this protection scheme, t

Currently, most secondary equipment in newly - built intelligent substations is placed inside prefabricated cabins located in the switchgear area. After the cabin bodies are manufactured, secondary equipment manufacturers enter the cabins for installation and debugging, resulting in a rather complex and cumbersome construction process. A typical 220 kV intelligent substation usually requires the setup of two prefabricated cabins: one for 220 kV and one for 110 kV. Both cabins are of Type II, wit

DefinitionA differential protection relay is one whose operation hinges on the phase difference of two or more electrical quantities. It operates based on the principle of comparing the phase angle and magnitude of the same electrical quantities.ExampleTake the comparison of the input and output currents of a transmission line as an instance. If the magnitude of the input current of the transmission line exceeds that of the output current, it indicates that additional current is flowing through

Action time characteristicsFixed-time overcurrent protection: the action time of the protective device is fixed, independent of the size of the fault current. No matter how much the fault current exceeds the setting value, as long as the action conditions are met, a pre-set fixed time will elapse before action is taken to trip or signal is issued. For example, if the set action time is 5 seconds, then when the current exceeds the set value, no matter how much it exceeds, the protection will be t

IntroductionWith the rapid development of technologies such as cloud computing and big data, and the accelerating penetration of "Internet +" into various industries, the digital economy industry is booming in major countries and regions around the world. It occupies an increasingly important position in daily life and the national economy. Especially under the current impact of the COVID - 19 pandemic globally, the downward trend of the world economy is intensifying. Only the digital economy ha

At present, in order to rationally enhance the efficiency and effectiveness of the engineering construction phase, deeply apply various design achievements in the application phase, promote the concept of full lifecycle management, comprehensively apply various new modern technologies, establish a unified and centralized equipment management interface, and improve the efficiency of intensive engineering in the design and construction stages, State Grid Corporation of China has started to impleme