Recently, TISCO successfully developed 750MPa-grade ultra-high strength non-oriented silicon steel with both magnetic and mechanical properties, which was supplied to a well-known domestic generator manufacturer in batches and successfully applied to the field of variable-speed pumped storage. The indicators of the products fed back by users fully meet the technical requirements and application requirements of high-head and large-capacity variable-speed pumping units, marking TISCO's first breakthrough in the application of this grade of silicon steel in this field in the world.

With the deepening of China's "double carbon" strategy, the demand for intermittent renewable energy such as wind power and photovoltaic is increasing year by year. In order to improve the stability of power grid, the new technology of variable speed pumped storage has become a new direction of power development in China. Therefore, a leading hydropower unit manufacturer in China has put forward the technical requirements of high head, high speed and large capacity variable speed pumped storage. The material for rotor core of this technology requires ultra-high strength non-oriented silicon steel products with 0.65mm specification and yield strength greater than 750MPa, so as to meet the requirements of wider adjustment range and lower energy consumption of variable speed generator sets. 

Due to the difficulty of material manufacturing, no enterprise at home and abroad has the stable supply capacity. After receiving the user's consultation, TISCO quickly set up a special group to deeply study the matching of chemical composition and recrystallization structure between the magnetic properties, strength and elongation of products and the process window, establish the process synergy mechanism between magnetic properties and mechanical properties, form the three-mechanism composite strengthening technology of silicon steel, successfully complete the product development within two months, and become the first enterprise in the world to successfully develop silicon steel products with a thickness of 0.65mm and a yield strength of 750MPa.

Deeply practicing the "customer-centered" service concept, TISCO's technical team participated in the whole process of user sample testing, coating material selection guidance and product standard formulation, providing a "package" solution from material development to application landing, helping customers to quickly realize technology transformation.At present, TISCO has developed 0.50mm and 0.65mm ultra-high-strength silicon steel series and special products for users' needs around the demand for ultra-high-strength silicon steel materials for the development of variable-speed pumped storage units, forming a full range of coverage in the strength range of 570MPa-750MPa, simultaneously completing the research on fatigue characteristics under different conditions, forming a complete set of patented technologies in manufacturing and application technology, and reaching the international leading level, helping the steady development of new technologies for variable-speed pumped storage power generation in China.