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The shape and corresponding structure of the contact will enable the vacuum arc column to rapidly diffuse into the vacuum area outside the arc column.   Once the interrupted current is zero, the temperature and voltage of the arc between the contacts will rapidly decrease, making the arc unable to continue and extinguish. Within a few US seconds after the arc is extinguished, the vacuum gap between the two contacts and the withstand voltage level will quickly recover.   At the same time, the distance between the contacts has also reached a certain level, which can withstand a high recovery voltage.   Therefore, after the current crosses zero, there will be no arc reignition and disconnection, which is the relevant principle of arc extinguishing in vacuum circuit breakers. At present, vacuum circuit breakers are widely used in the power industry and are very important components in the power industry.   The functional requirements for vacuum circuit breakers vary in different application fields. At present, there are many types of vacuum circuit breakers sold in the market, each with different functions and prices.

Vacuum circuit breakers are currently widely used in industrial production and distribution, with common products such as VS1-12 vacuum circuit breakers. However, due to their high rated voltage, high current, and strong flying ability, there are many problems and hidden dangers. Improper handling can lead to many accidents. Therefore, this requires us to strengthen management in the selection, installation, operation, and maintenance of vacuum circuit breakers, monitor and diagnose the status of the operating vacuum circuit breakers, and promptly and accurately handle common faults.   vacuum circuit breaker   1. Debugging and handover tests must strictly control the debugging and handover tests of the equipment to prevent any changes during transportation or mismatches that may occur after adjusting the mechanism, especially after connecting the operating mechanism to the vacuum circuit breaker. The main parameters to be retested include: closing bounce, opening synchronization, opening distance, compression stroke, closing and opening speed and time, DC resistance, opening and closing action voltage value, fracture insulation level, transmission acceptance test, etc. All of these parameters should meet the requirements. In our routine maintenance work, we mainly found the following problems: the expansion baffle of the static contact in the circuit breaker cabinet and the handcart circuit breaker frame got stuck, causing difficulty in entering the vehicle, the bounce and stroke of the circuit breaker were not qualified, the insulator porcelain bottle of the circuit breaker body was damaged due to being too close to the pull rod, the closing contactor had poor operating characteristics, often unable to operate or the operating voltage gradually increased after one operation, and the vacuum degree of the vacuum bubble did not meet the requirements. We have dealt with these problems. The debugging and handover testing of vacuum circuit breakers must be strictly carried out. We need to promptly detect insulation breakdown, structural abnormalities, vacuum arc extinguishing chamber leaks, and abnormal bouncing, speed, and travel before putting it into operation to ensure safe operation. 2. Operation and maintenance, regular inspection 2. 1. During operation and maintenance, pay attention to observing for any abnormal phenomena, such as abnormal discharge sounds after the circuit breaker is disconnected. When powering on, observe for cracks or damage in the vacuum arc extinguishing chamber. Report any abnormalities immediately and wait for maintenance confirmation before proceeding with the operation. 2.2. Regular inspection of common defects in the vacuum circuit breaker body includes: leakage of the vacuum arc extinguishing chamber, breakdown of the insulation parts of the body, unqualified overvoltage protector, unqualified DC resistance of the vacuum arc extinguishing chamber, and refusal to close the circuit breaker when put into operation. Regular withstand voltage tests, measurement of vacuum degree, determination of DC resistance and opening and closing action voltage values are important means of discovering the above-mentioned defects. 3. Status Monitoring and Diagnosis of Vacuum Circuit Breaker The vacuum arc extinguishing chamber is a key component of a vacuum circuit breaker. It is supported and sealed with glass or ceramic, and contains dynamic and static contacts and shielding covers. The vacuum degree should not be lower than 6.6 x 10-2P a. The vacuum arc extinguishing chamber manufactured by the factory is required to be below 7.5 x 10-4Pa. When the vacuum degree decreases, its breaking performance significantly decreases. Therefore, the vacuum arc extinguishing chamber cannot be struck or impacted by any external force. 3.1 Inspection of Vacuum Arc Extinguishing Chamber The characteristic of a vacuum circuit breaker is that the contacts are sealed inside the insulated shell of the vacuum arc extinguishing tube. It is manufactured using modern equipment under strict quality management, ensuring a long service life. Inspection is required in the following situations, if necessary Need to replace vacuum bubble: (I) When the vacuum arc extinguishing chamber has reached the guaranteed number of on-off cycles by the manufacturer (mechanical life of 10000 cycles); (2) The vacuum arc extinguishing chamber has reached the specified inspection cycle (when the number of opening and closing cycles reaches 10000 times and the short-circuit current reaches 100 times, the withstand voltage test of the arc extinguishing chamber is carried out, and when it reaches 20000 times, the vacuum arc extinguishing chamber is replaced); (3) When abnormalities are found in appearance. Inspection basis: The lifespan of a vacuum circuit breaker is determined by two indicators: the contact and vacuum degree (1) Measure contact wear. Mark the contact rod of the vacuum circuit breaker to check or measure the contact overtravel with a vernier caliper. If the accumulated wear thickness of the moving and stationary contacts exceeds the specified range, it indicates that the electrical life of the vacuum bubble has ended and the vacuum bubble should be replaced. (2) The DC resistance of the vacuum bubble is within the specified range. The DC resistance of a general vacuum bubble is not greater than 25 μ Ω, and the conductive circuit resistance of a vacuum circuit breaker is not greater than 45 μ Ω (3) Vacuum degree measurement. ① Power frequency withstand voltage method. Place the circuit breaker in the open state and apply voltage between the contacts of the vacuum arc extinguishing chamber to determine if it can withstand 42kV and Imin power frequency withstand voltage tests. If there is no continuous discharge inside the vacuum bubble, it is considered normal. ② ****** Testing. The currently better method is the magnetron method, which is suitable for testing vacuum arc extinguishing chambers in manufacturing plants. The vacuum degree is not greater than 5 * 10-4Pa, ③ Spark gauge method. Only applicable to glass tube vacuum arc extinguishing chambers. When in use, move the spark leak detector on the surface of the arc extinguishing chamber, and there will be different luminescence situations inside under the action of its high-frequency electric field. If there is a light blue glow inside the tube, the vacuum degree should be above 1.33 * 10-5; If it shows red and blue light, it indicates that the tube has failed; If the tube is already in an atmospheric state, it will not emit light.

On November 30th, at the West First Restaurant, the group held a unique birthday celebration party for new and old employees whose birthdays were in November. General Manager Guo Wenwu and President of West First Business School Cheng Xiaoxue attended the event, sending their blessings to the birthday employees and encouraging everyone to work hard for a better tomorrow at West First and create new achievements.

On October 23rd, Zhang Zhigang, Chairman and Party Secretary of State Grid Corporation of China, held talks with Liu Guoyue, Party Secretary and Chairman of State Energy Investment Group Co., Ltd. at the company headquarters, deeply implementing the important speech and instructions of General Secretary * * on energy and electricity, implementing the new energy security strategy of "four revolutions and one cooperation", ensuring reliable power supply, promoting green energy transformation, and accelerating the construction of new power systems and new energy systems. Chen Guoping, Deputy General Manager and Party Member of State Grid Corporation of China, and Fu Zhenbang, Party Member and Deputy General Manager of State Energy Group, signed the "Strategic Cooperation Agreement for Jointly Promoting the Construction of the Southern Xinjiang New Power System Demonstration Zone" on behalf of both parties.       Zhang Zhigang welcomes Liu Guoyue and his delegation to visit State Grid Corporation of China, and thanks State Energy Group for its support and assistance in the company's work.   State Grid Corporation of China and State Energy Group have a good foundation for cooperation, and we look forward to both sides leveraging their respective advantages, fulfilling their common mission and responsibilities, and continuously deepening all-round cooperation in ensuring safe and reliable power supply, promoting green and low-carbon energy transformation, building a unified national electricity market, promoting the implementation of major energy projects, and strengthening enterprise management, making greater contributions to safeguarding national energy security and promoting energy transformation.   image   Liu Guoyue thanks State Grid Corporation of China for its long-term support and assistance to the work of the National Energy Group. He stated that State Grid Corporation of China fully leverages the "three roles" of central enterprises, actively serves the implementation of major national strategies, and has carried out effective work in the construction of new power systems, technological innovation, improvement of people's livelihoods, and brand building. The National Energy Group has a full industry chain business including coal, electricity, transportation, and chemical industry. It deeply implements the development strategy of "one goal, three roles, and six responsibilities" to ensure the safety and stability of the power system and serve the goals of carbon peak and carbon neutrality. We hope that the signing of this strategic cooperation agreement will serve as an opportunity for both parties to strengthen exchanges and cooperation in areas such as clean energy development and utilization, key project planning and construction, green power trading, and digital transformation, accelerate the construction of new power systems, and promote high-quality development of energy and electricity.       Zhang Shishan, Assistant General Manager of National Energy Group and Director of Power Industry Management Department, Ding Maoting, Deputy Chief Economist and Director of Comprehensive Management Department, as well as relevant department and unit heads, Liu Kejian, Assistant General Manager and Office Director of State Grid Corporation of China, Li Ming, Deputy Chief Engineer and Director of Marketing Department, and relevant department and unit heads attended the event.  

1、 Load switch   A control electrical device with a simple arc extinguishing device that can carry load on and off circuits. It can interrupt a certain load current and overload current, but cannot interrupt short-circuit current. It must be used in series with a high-voltage fuse to cut off short-circuit current.   The function of load switch:   1. Disconnect and close cooperation. Due to its arc extinguishing ability, it can be used to disconnect and close load currents and overload currents that are less than a certain multiple (usually 3-4 times); It can also be used to open and close no-load transformers with larger capacity than isolation switches, longer no-load lines, and sometimes large capacity capacitor banks.   2. Alternative role. The series combination of load switch and current limiting fuse can be used instead of circuit breaker. The load switch is responsible for breaking and closing overload currents that are less than a certain multiple, while the current limiting fuse is responsible for breaking larger overload currents and short-circuit currents.   3. A load switch that is combined in series with a current limiting fuse is referred to as a "load switch fuse combination" in national standards. The fuse can be installed on the power side of the load switch or on the receiving side of the load switch. When it is not necessary to frequently replace the fuse, the former arrangement should be adopted in order to utilize the function of the load switch as an isolation switch to isolate the voltage applied to the current limiting fuse.   2、 Isolation switch   A control electrical appliance without an arc extinguishing device, whose main function is to isolate the power supply to ensure the safe maintenance of other electrical equipment, therefore, it is not allowed to operate with load. But under certain conditions, it is allowed to turn on or off low-power circuits. It is a widely used and frequently used electrical device in high-voltage switches The function of isolation switch:   After disconnection, establish a reliable insulation gap and separate the equipment or line that needs maintenance from the power supply with a clear disconnect point to ensure the safety of maintenance personnel and equipment.   2. Change the circuit according to operational needs.   3. It can be used to separate and combine small currents in power lines, such as the charging current of bushings, busbars, connectors, and short cables, the capacitance current of switch voltage equalization capacitors, the circulating current during double busbar switching, and the excitation current of voltage transformers.   4. According to the specific situation of different structural types, it can be used to separate and combine the no-load excitation current of a certain capacity transformer.   High voltage isolating switches can be divided into outdoor high-voltage isolating switches and indoor high-voltage isolating switches according to their installation methods.   Outdoor high-voltage isolation switch refers to a high-voltage isolation switch that can withstand the effects of wind, rain, snow, dirt, condensation, ice, and thick frost, and is suitable for installation on terraces.   According to the different insulation pillar structures, it can be divided into single column isolation switches, double column isolation switches, and three column isolation switches. The single column isolation switch directly uses the vertical space under the overhead busbar as the electrical insulation for the break, therefore, it has obvious advantages such as saving floor space, reducing the number of connecting wires, and having a particularly clear opening and closing state. In the case of ultra-high voltage transmission, the use of single column isolation switches in substations has a more significant effect on saving floor space.   Isolation switches are mainly suitable for low-voltage terminal distribution systems in residential and building areas.   3、 Vacuum circuit breaker   Named after its high vacuum insulation medium for both the arc extinguishing medium and the contact gap after arc extinguishing; It has the advantages of small size, light weight, and is suitable for frequent operation and arc extinguishing without maintenance, and is widely used in distribution networks.   Vacuum circuit breaker is an indoor distribution device in a 3-10kV, 50Hz three-phase AC system, which can be used for the protection and control of electrical equipment in industrial and mining enterprises, power plants, and substations. It is particularly suitable for places that require oil-free, low maintenance, and frequent operation. Circuit breakers can be configured in central cabinets, double-layer cabinets, and fixed cabinets for the control and protection of high-voltage electrical equipment.   1. Working principle of vacuum circuit breaker   When the moving and stationary contacts are opened under the action of the operating mechanism, an arc is generated between the contacts, and steam is emitted from the surface of the contacts at high temperatures. Due to the special shape of the contacts, a magnetic field is generated when current passes through, and the arc moves rapidly along the tangent direction of the contact surface under the action of this magnetic field. Part of the metal vapor condenses on the metal cylinder (shielding cover), and the arc is extinguished at natural zero crossing, and the dielectric strength between the contacts quickly recovers.   2. Function of vacuum circuit breaker   Circuit breakers have overload, short circuit, and undervoltage protection functions, and have the ability to protect circuits and power sources.   4、 The difference between load switch and isolation switch The difference is that the two cut off different currents.   Because the isolation switch does not have an arc extinguishing device, it is only suitable for cutting off no-load current and cannot cut off load current or short-circuit current. Therefore, the isolation switch can only be operated safely when the circuit is safely disconnected, and it is strictly operated with load to avoid safety accidents. Due to the arc extinguishing device, the load switch can overload current and rated load current, but it cannot cut off short-circuit current.   The second point is that the load switch has an arc extinguishing device, while the isolation switch does not have such a device.   So what's different about this arc extinguishing device? The so-called arc extinguishing device is designed to better assist in the opening and closing of switchgear, as well as effectively limit the arc and help extinguish it. There is such an arc extinguishing device, which is safer for switchgear. So most switch devices are equipped with arc extinguishing devices. Especially household switch appliances.   The third point is that the roles of the two are different.   Due to the lack of arc extinguishing devices, isolation switches can only be used to isolate the live and power-off parts of high-voltage circuit devices, in order to ensure the maintenance and inspection of high-voltage circuits by personnel and ensure their safety.   The load switch is applied to fixed high-voltage equipment, which can cut off the fault current and rated current in the high-voltage equipment. Therefore, their functions are different, but both are applied to high-voltage equipment.   5、 The difference between high-voltage load switch and vacuum circuit breaker   1. High voltage load switches can be used for load breaking and have a self extinguishing arc function, but their breaking capacity is very small and limited.   2. High voltage isolating switches are generally not capable of breaking loads. They do not have arc extinguishing enclosures in their structure, and there are also isolating switches that can break loads, but their structure is relatively simpler compared to load switches.   3. High voltage load switches and high-voltage isolation switches can both form obvious disconnection points. Most circuit breakers do not have isolation functions, and there are also a few circuit breakers with isolation functions.   4. High voltage isolation switches do not have protection functions, and the protection of high-voltage load switches is generally achieved by adding fuses, only with quick break and overcurrent protection.   The breaking capacity of high-voltage circuit breakers can be made very high during the manufacturing process. Mainly relying on the use of current transformers in conjunction with secondary equipment for protection. It can have functions such as short circuit protection, overload protection, and leakage protection.   High voltage load switch is an electrical device that functions between high-voltage circuit breaker and high-voltage isolation switch. High voltage load switch is often used in series with high-voltage fuse; Used for controlling power transformers. High voltage load switches have simple arc extinguishing devices because they can switch on and off certain load currents and overload currents. But it cannot disconnect short-circuit current, so it is usually used in series with high-voltage fuses to provide short-circuit protection.

1、 Firstly, we must understand what a sealed vacuum circuit breaker is?   1. Sealed vacuum circuit breakers ensure creepage distance and insulation performance, making them smaller in size, more space saving, and effectively protecting the vacuum arc extinguishing chamber from impact and collision. They have strong resistance to environmental pollution and can be used in harsh environments.   2. Fixed sealed circuit breaker, also known as a shortened form of fixed sealed pole type circuit breaker. Sealed circuit breakers also belong to vacuum circuit breakers, which differ from ordinary vacuum circuit breakers only in the material of the packaging. However, when it comes to deeper technical issues, there are significant differences between sealed circuit breakers and ordinary vacuum circuit breakers.   3. Sealed circuit breakers are encapsulated by pouring epoxy resin outside the original vacuum bubble.   2、 What is the difference between solid sealed vacuum circuit breakers and non solid sealed vacuum circuit breakers?   1. Compared with different assembled poles, the number of parts in the fixed sealed pole is greatly reduced, the structure is simple, the installation is convenient, the manufacturing process of the circuit breaker is simplified, and the reliability and stability of the circuit breaker are greatly improved.   2. Fixed sealed insulation has better insulation than non fixed sealed insulation, and also has good moisture-proof and anti condensation properties, making it suitable for use in high-temperature and humid areas. But heat dissipation is not as good as non sealed ones. Generally, design institutes determine the design based on the usage environment, so I think that as long as it is a place with high humidity, a fixed seal type should be used. However, the rated current should not be too high, and if it is too high, the temperature of the vacuum tube will be difficult to dissipate quickly   3、 The function and application of vacuum arc extinguishing chamber in vacuum circuit breaker:   1. Due to the vacuum arc extinguishing chamber being embedded in epoxy resin insulation material, it transforms the original surface insulation into volume insulation, so no further treatment is required. The fixed sealing pole can achieve high insulation strength, which is more conducive to the miniaturization design of circuit breakers and switchgear.   2. The vacuum arc extinguishing chamber and related conductive components are simultaneously embedded in epoxy resin solid insulation material, shielding it from external environmental influences. It is completely maintenance free during the product's service life, making it highly adaptable and widely applicable in various fields such as chemical, metallurgical, mining, etc.   3. Although its production cost is relatively high, the main circuit that encapsulates the low resistance vacuum arc extinguishing chamber and outlet socket in epoxy resin improves the insulation level and anti pollution ability, eliminating the influence of condensation.   4. In response to the usage environment of switchgear, adopting a fixed sealed pole form can better meet the needs of more users, increase the reliability of switchgear, and improve the power supply reliability of the power grid.  

The market value of Schneider Electric, a French power equipment manufacturer, exceeds that of Total Energy, the country's largest oil and gas producer, marking an acceleration in the transition from fossil fuels to electrification.         Since the beginning of this year, Schneider's stock price has risen by 35%, and its market value in Paris has increased to approximately 142 billion euros (158 billion US dollars, approximately 1106 billion RMB), making it the fourth largest company in the French CA * * 0 stock index. Schneider has a wide range of products, from switchgear to software for managing power grids and factories. Its market value is second only to luxury fashion group and cosmetics giant LVMH Mo ë t Hennessy Louis Vuitton SE, Herm è s International SCA, and L'Oreal SA in France.       During the same period, the market value of Total Energy fell by 5% to around 140 billion euros, reflecting a decline in global energy prices due to doubts about demand intensity.         This is a competition between future energy and past energy, "said Gilles Guibout, head of European stocks at Anson Investment Management in Paris. We are electrifying the world, and Schneider is at the core of this structural trend       The rise of Schneider reminds us that addressing climate change and the flourishing development of artificial intelligence require significant investments in renewable energy, more complex power grids, and data centers. Schneider Electric announced last Thursday that it will pay approximately $850 million to acquire a controlling stake in Motivair Corp, a high-performance computing liquid cooling expert, to strengthen its offerings for rapidly growing data centers. This all cash transaction is expected to be completed in the coming quarters, with Schneider acquiring 75% of Motivair's shares in the United States and planning to acquire the remaining shares by 2028. The company stated in a statement that this transaction enhances Schneider's direct chip liquid cooling and high-capacity thermal system products.       The company added that the surge in the use of large-scale language models such as generative AI and Chat GPT requires more efficient cooling solutions in data centers, especially liquid cooling, as traditional air cooling cannot dissipate greater heat.       Schneider CEO Peter Herweck said that the device manufactured by Motivair, headquartered in Buffalo, New York, can pump coolant at very high pressure near the chip, effectively cooling servers.       Herweck added that the data center and networking market will account for 21% of Schneider's 2023 orders, or approximately 8 billion euros (8.7 billion US dollars) in sales, and will achieve double-digit growth this year.       Goldman Sachs estimates that in the US market, the electricity consumption of data centers is expected to approximately double between 2023 and 2030, requiring approximately 47 gigawatts of next-generation power generation capacity.       The United States is the largest market, but demand for data centers is also growing elsewhere.       Schneider's stock price has risen by over 30% this year, thanks to its strong market position.

On January 20, the the Year of the Loong Annual Meeting and Award Ceremony of Xiyi Electric Group Co., Ltd. was held in Xianju Huangjia Hotel as scheduled.   Chairman Shi Chengda delivered a New Year's speech, and employees from various departments of the company gathered together to discuss and share their gains and joys in work and life, showcasing their youthful and energetic talents. The scene was filled with laughter and joy.