Addtime：2023-06-05 13:40:06 Resource：ShenGaosuo Electric Co., Ltd.

Recently, the Ministry of Industry and Information Technology announced the fourth batch of manufacturing single champion list, and Xu Ji HVDC converter valve products were successfully selected.

In recent years, the state has vigorously promoted the high-quality development of the manufacturing industry, and the Ministry of Industry and Information Technology has organized the selection of single champions of the manufacturing industry nationwide, aiming to accelerate the cultivation of national industry vanguards with innovative capabilities and world-class enterprises with global competitiveness. Xuji Group conscientiously implements the requirements for the high-quality development of China's manufacturing industry, seizes the strategic opportunity of "three types and two networks, world-class" of the State Grid Corporation, focuses on core business, cultivates meticulously, actively cultivates "hidden champion" products, sorts out 6 "hidden champion" products and 9 "leading" products, and creates unique core competitiveness.

Xuji's HVDC converter valve products were successfully awarded the fourth batch of manufacturing single champion products of the Ministry of Industry and Information Technology, which is a full recognition of Xuji's R & D and manufacturing level of converter valve equipment, and also a high affirmation of Xuji's independent innovation ability in the field of HVDC transmission, which is of great significance to Xuji's efforts to build a champion product system and promote the high-quality development of the industry.

Opening the scroll of China's HVDC transmission development, the figure of Xu Ji converter valve appears frequently, rendering the scientific and technological picture of China's power transmission: successfully won the bid for the first Chinese-based Guiguang II return project, has provided core equipment for more than 30 high-voltage, ultra-high-voltage projects and flexible HVDC transmission projects, created a number of world firsts in HVDC transmission technology, and has successively won the special prize and first prize of National Science and Technology Progress Award, China Industry Award, China Quality Award Nomination Award, etc. As a manufacturer of converter valves for core equipment, Xu Ji, with the development of China's DC transmission, has never stopped the pace of technological innovation.

A pioneer in converter valve technology from "nil" to "yes"

In 1986, Xu Ji began to undertake the national HVDC transmission technology research and DC equipment development tasks, introduced DC core technology, and began to carry out complete sets of equipment research and development; In 2005, Xu inherited the first localization project and successfully developed 500 kV light-controlled converter valve equipment, filling the domestic gap. Behind the localization process is too much hardship day and night.

Valve control (VCE) and thyristor control unit (TCE) are the core components of UHVDC converter valves, if the converter valve is the heart of UHVDC transmission system, VCE and TCE are the nerve centers of the heart. VCE and TCE technology were monopolized by a small number of foreign enterprises in the early stage and blocked by foreign technology, which is a "black box" for domestic complete sets of manufacturers, which brings great difficulties to the early DC engineering operation and maintenance and fault analysis. Xu Ji's R&D team deeply recognizes the necessity and urgency of independent research and development of VCE and TCE, and is determined to successfully develop China's own VCE and TCE. At that time, the domestic understanding of VCE and TCE was a blank paper, and there were very few materials that could be referenced, and the development was very difficult. Xu Ji's R&D team has repeatedly considered, discussed, tested and demonstrated the design principle, device selection, wiring process, reliability test and other links, relying on the tenacious spirit of independent innovation, successfully conquered the core key technologies in 2 years, developed VCE and TCE products with completely independent intellectual property rights for the first time, and successfully applied them in the Gezhouba-Nanqiao DC transformation project in 2010, taking a key step in the autonomy of UHVDC converter valve products.

From "have" to "excellent" converter valve technology leader

From the introduction of foreign advanced technology, to independent innovation, breaking the long-term monopoly of foreign enterprises in this field, and then reaching the international leading level, Xu Ji has comprehensively overcome a set of core key technologies such as UHVDC converter valve system analysis, product design, manufacturing process, equivalent test and engineering implementation with the continuous pursuit of technology, and successfully developed a number of converter valve products that create "the world's first" and "the world's best", step by step to the commanding heights of the world's DC transmission.

From "have" to "excellent", the leading technology needs to be escorted by testing, and test capability is a key part of the research and development process of UHVDC converter valves. In the early construction of UHVDC transmission projects in China, the converter valve equipment was supplied by foreign manufacturers, and the key tests of converter valves were also carried out abroad. Without its own UHV test technology capabilities, it is impossible to talk about independent research and development. Faced with this major technical problem, Xu Ji's R&D team repeatedly compared and demonstrated the construction scheme of the test system through theoretical analysis, modeling and simulation, and proposed a test method based on electrical stress equivalent synthesis for the first time, and successively built the converter valve synthesis test circuit system, UHV insulation test hall, and flexible DC converter valve operation test system, which fully met the technical requirements of all test capabilities of UHVDC converter valves, and the test capacity reached the world-class level.

A new era of flexible DC converter valves, opening a new era with new technologies

"Do a project, build a brand, build a monument", Xu Ji with his own product advantages and integration capabilities, actively invested in the national major DC engineering applications, effectively driving the progress of the DC transmission industry. In 2017, it won the bid for the Mera DC transmission project in Pakistan and the back-to-back DC transmission project in Van, Turkey, realizing the DC transmission technology to go abroad and providing strong support for the national "Belt and Road" construction. In September 2019, Xu Ji won the bid for China's first offshore wind power flexible direct transmission project - such as the East Offshore Wind Power Flexible DC Transmission Demonstration Project, contributing new technologies to the new era of DC transmission and achieving new leadership.

Flexible HVDC transmission is a new generation of HVDC transmission technology, which has more flexible control characteristics than conventional HVDC transmission technology, and is especially suitable for application scenarios such as offshore wind power transmission, island power supply, and hybrid HVDC transmission. For a long time, the reliable operation of flexible DC converter valve has been plagued by the problem of "black module", that is, the failure of a single component, resulting in the loss of contact between the module unit of the converter valve and the monitoring system, which in turn leads to the problem of stopping power supply after the DC system is blocked and tripped, which poses a risk to the continuous and reliable power supply of flexible DC, and the "black module" has become a world-class technical problem. Xu Ji and the owner jointly set up a public relations team, after nearly a Chinese New Year's Eve of hard work, after dozens of highly risky overpressure breakdown test demonstrations, in September 2019 took the lead in overcoming the "black module" technical problems in China, and the successfully developed ±800 kV/5000 MW UHV flexible DC converter valve will be applied in the world's first UHV multi-terminal hybrid DC project - Wudongde Power Station Transmission Guangdong Guangxi Multi-terminal DC Demonstration Project. In the national DC project bidding in the past three years, Xuji converter valve market share is the first in China.

Thirty years of wind and rain, the vicissitudes of the sea have become mulberry fields. As a pioneer, practitioner and leader of China's independent innovation and development of HVDC transmission, Xu Ji has contributed positive forces to the development of China's power grid. In the near future, Xu Ji will continue to increase the research and development of UHV converter valve technology, continue to lead the development of the industry, and provide more and more effective Chinese solutions to support the "Belt and Road" strategy and high-end equipment going abroad.