-- Provide electronic engineers with downloadable electronic materials such as new solutions, new reference designs, and new design concepts that inspire innovation! -- Provide electronic engineers with technical articles on product design, including technical analysis, design tips, design tools, and test tools! -- Provide circuit diagrams such as electronic circuit diagrams, schematic diagrams, automotive circuit diagrams, mobile phone circuit diagrams, amplifier circuit diagrams, and power supply circuit diagrams. Relay protection is an important measure to detect faults or abnormal conditions in the power system, thereby issuing alarm signals or directly isolating and removing the faulty part. This article mainly introduces the ranking status of the top ten relay protection manufacturers in the world, for reference only. Nanjing NARI Relays Electric Co., Ltd. (referred to as "NARI Relays") mainly engages in the research and industrialization of power protection control and intelligent power equipment for power grids, power plants, and various industrial and mining enterprises. It is the largest scientific research and industrialization base in this field in China. In 2010, the National Energy Administration established the "National Energy Power Control Protection Technology R&D (Experimental) Center" at NARI Relays. NARI Relays adheres to the development strategy of "refining the main business and expanding externally," continuously improving and enhancing existing core technologies, always maintaining industry leadership, while steadily expanding into related technical fields. Currently, the company is actively exploring fields such as power system relay protection, power grid security and stability control, substation automation, power plant automation, primary intelligent equipment, process control in large industrial fields, and new energy. Leveraging its technical advantages in control and protection, it is achieving comprehensive expansion and deepening of its industry. The company has also increased its international market development efforts, and NARI Relays products have been exported to more than 90 countries and regions worldwide. Guodian Nanjing Automation Co., Ltd. (listed on the Shanghai Stock Exchange on November 18, 1999) is the first high-tech listed company in the national power system, known as the first stock of China's power high-tech, and is now a directly affiliated subsidiary of China Huadian Corporation. The predecessor of Guodian Nanzhi was the Nanjing Power Automation Equipment Factory, founded in 1940. After the founding of New China, the company successively researched and produced China's first and second generation static relay protection products in the field of power automation, and created many national firsts, known as the pioneer of modern power automation products in China. The company is one of Nanjing's top 50 industrial enterprises, a key high-tech enterprise under the National Torch Plan, one of the top ten (China) innovative outstanding enterprises, and a backbone enterprise of the national power automation industry base. Its products have won the "China Famous Brand" title. The company's main business areas include: power grid automation, power plant automation, water conservancy and hydropower automation, rail transit automation, industrial automation, information and security monitoring systems, geotechnical and dam safety monitoring systems, new energy and energy conservation and emission reduction, water environment protection, and intelligent primary equipment. XJ Electric was established in March 1993, with Xuchang Relay Factory as the sole sponsor, restructured through targeted placement. On April 18, 1997, XJ Electric was listed on the Shenzhen Stock Exchange. XJ Electric is the first listed company in the domestic industry, one of the first council units of the China Association for Public Companies, a national key high-tech enterprise recognized by the Ministry of Science and Technology, and has a national-level enterprise technology center and enterprise postdoctoral workstation. After more than 20 years of vigorously promoting mechanism reform and technological innovation, the company has become a large backbone and leading enterprise in China's power equipment industry, with products covering all aspects of the power system such as power generation, transmission, distribution, and consumption, spanning primary and secondary, high and medium voltage, AC and DC equipment fields. It is one of the most competitive power equipment manufacturers and system solution providers with the strongest comprehensive supporting capabilities in China, undertaking a series of major research projects during the national "Sixth Five-Year Plan" to "Twelfth Five-Year Plan" periods. The company's products are widely used in national key projects such as "West-East Power Transmission," "West-East Gas Transmission," "South-North Water Diversion," nuclear power construction, and high-speed railway construction, and are exported to more than 20 countries and regions, making outstanding contributions to the safe, stable, and economic operation of power systems in China and abroad. Beijing Sifang Jibao Automation Co., Ltd. is a national high-tech enterprise, national-level enterprise technology center, and listed company (stock code: 601126) established in 1994. Its founder is Professor Yang Qixun, one of the first academicians of the Chinese Academy of Engineering and "the father of China's microcomputer relay protection," a master in the field of electrical automation in China. Currently, Sifang Co., Ltd. has nearly 4,000 employees, including nearly 1,000 in the technical R&D team; the company's total assets exceed 5 billion yuan, and it has established multiple R&D and production bases in Beijing, Wuhan, Baoding, Nanjing, and other places. As a leading enterprise in China's electrical and industrial automation industry, Sifang Co., Ltd. always adheres to the macro vision of "becoming a globally renowned brand of high-tech, professional automation products, systems, solutions, and service providers." Since its establishment, Sifang Co., Ltd. has upheld the corporate purpose of "leading technology, always innovating," focusing on product design, software development, system solutions, and technical consulting in multiple fields such as smart power generation, smart power transmission and distribution, smart transportation, smart ships, and smart islands. Its main products include power station automation systems, relay protection, ship electrical integrated automation systems, dispatch automation systems, power plant automatic control systems, power security and stability control systems, microgrid control systems, energy storage control systems, power quality management systems, electrical simulation training systems (including ships), centralized control and monitoring systems, energy management systems, rail transit automation systems, and industrial control systems. Changyuan Shenrui Relay Protection Automation Co., Ltd. (hereinafter referred to as Changyuan Shenrui) is a wholly-owned subsidiary of Changyuan Group (stock code: 600525.SH), a mainboard listed company in China, specializing in relay protection and automation. It is a national high-tech enterprise. Originally named Shenzhen NARI Technology Co., Ltd., it was restructured in 1994 from the Component Protection and Substation Integrated Automation Research Office of the Electric Power Automation Research Institute of the Ministry of Electric Power. It is one of the first enterprises in China to engage in scientific research, production, and service of microcomputer protection and substation integrated automation projects. Headquartered in Shenzhen, it has R&D bases in both Shenzhen and Nanjing. Changyuan Shenrui specializes in technical research, product development, production and sales, and related technical services in the fields of power system protection and control, distribution automation, and industrial automation. The company integrates global resources, focusing on the five major power links of "generation, transmission, transformation, distribution, and consumption," aiming to maximize customer benefits, providing users with secondary equipment and system integration solutions for the power industry, as well as integrated engineering project services including consulting, design, construction, and commissioning. Beijing Deweite Power System Automation Co., Ltd. was established in July 1996. It is a high-tech enterprise approved and registered by the Zhongguancun Science and Technology Park in Beijing and is an enterprise approved by the State Economic and Trade Commission for the national urban and rural power grid construction and renovation. The company is committed to the research, development, production, sales, and service of high-tech products such as microcomputer relay protection monitoring devices, substation integrated automation systems, and dispatch automation systems. Since its establishment in 1996, the company has successively launched several major series and dozens of power automation products, including DVP-500 series, DVP-600 series, DVP-700 series, DVP-9000 series fully distributed microcomputer relay protection monitoring devices, DVT-2000 microcomputer relay protection test systems, DVPS-600 substation integrated automation systems, and DVPS-3000 power plant and substation integrated automation systems. The products have been widely used in industries such as electric power, light industry, chemical industry, petrochemical, petroleum, metallurgy, and military industry, accumulating rich field operation experience. Beijing Guozijibao Power Equipment Technology Co., Ltd. was founded in 2000. The company is a professional limited company integrating R&D and sales of power system relay protection, automation devices, high and low voltage reactive power compensation devices, capacitor composite switches, and related power electronics technology. The company is a high-tech enterprise registered in China's "Silicon Valley," the Zhongguancun Information Industry Base in Haidian District, Beijing. The company has a complete R&D institution in Beijing, with a professional development team with many years of experience in power system protection automation, high and low voltage reactive power compensation devices, and composite switch R&D. Adhering to the R&D spirit of "innovation" and "refinement," it continuously launches high-quality products. The company has a production and service base in Zhangjiagoukou, branch companies in Xi'an and Wuhan, and agents in Shijiazhuang, Harbin, Dalian, Shenyang, Taiyuan, Jinan, Daqing, Lanzhou, and Urumqi. It can provide high-performance, high-reliability protection automation products and professional technical support and services for users in the power system, oilfield enterprises, and industrial and mining enterprises. The company passed the ISO9001-2000 version quality system certification by UK UAKS in 2001, and its products have passed the inspection of the National Power Equipment and Instrument Testing Center and the National Relay Quality Supervision Center. In 2003, it passed the expert appraisal organized by the Relay Protection Professional Committee of the Chinese Society for Electrical Engineering, with the conclusion that the HW3000 substation integrated automation system is currently at the domestic leading level. The products have passed the sampling inspection of the National Relay Quality Supervision and Testing Center twice and passed once. Since the products were launched in 2000, they have been put into operation in more than 500 substations and distribution stations in power, petrochemical, metallurgy, coal, building materials, and other systems, with stable and good operation and high reputation. Yantai Dongfang Electronics Information Industry Group Co., Ltd. is a large high-tech enterprise group integrating scientific research and development, production and operation, technical services, and system integration. Its main business is power system automation, informatization, and energy management system solutions. It is one of the key high-tech enterprises supported by the state and Shandong Province. Dongfang Electronics was founded in 1971. In 1975, it developed the computer auxiliary equipment - photoelectric input machine, and in 1980, it won the first national quality award silver medal in China's computer industry. In 1982, it cooperated with Shandong University of Technology to develop China's first microcomputer power telecontrol equipment, bringing the enterprise into the field of power system automation. After more than 30 years of development, the company now has 11 subordinate enterprises including a listed company, with total assets of 2.2 billion yuan. It currently has more than 2,000 employees, with 70.43% holding bachelor's degrees or above. Its products cover power automation, informatization, and fields such as railways, energy (mines, oilfields, large smelting and chemical industries). Currently, it has multiple varieties including power plant automation, protection and substation integrated automation, distribution automation, electric energy metering and billing management, enterprise information management, intelligent communication power supplies, and wireless. Switchgear, low-voltage switchgear, industrial process automation control systems, and DC power supply systems can meet the requirements of various power plants and substations for relay protection and automatic control equipment. In addition, Ajie Company also manufactures protection and automation equipment for electrified railway traction substations, electrical automation equipment for urban light rail transit, grain storage automatic control equipment, and precision molds. Shenzhen NARI Technology Co., Ltd. (hereinafter referred to as Shenzhen NARI) is located in the north area of Nanshan Science and Technology Park, Shenzhen. It is a well-known domestic high-tech enterprise in the power automation industry. Shenzhen NARI specializes in the R&D, commissioning and testing, sales, and related engineering design and services of power system automation products. Its products and services have covered more than 4,000 substations with voltage levels from 35kV to 500kV in the national power grid (among which the BP series microcomputer bus protection devices have reached the international leading level, with a market share exceeding 50%). It is one of the five major manufacturers in the field of substation integrated automation control in China, and is also the largest professional power system automation company in South China. Shenzhen NARI is also an important industrial base for NARI Group's ultra-high voltage technology R&D.