The National Key Laboratory of Sensor Technology at the Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences has achieved a significant breakthrough with the successful development of a high-performance quantum current sensor leveraging negatively charged nitrogen-vacancy centers in diamonds. This groundbreaking sensor has successfully passed the rigorous technical appraisal organized by China Southern Power Grid Company. The appraisal committee, esteemed with academicians and experts such as Li Licheng and Chen Yong from the Chinese Academy of Engineering, unanimously concurred that the sensor's technical prowess surpasses international standards and is fully capable of meeting the stringent demands of ±800kV Ultra-High Voltage (UHV) transmission lines. This accomplishment marks another crucial milestone in the practical deployment of indigenous quantum sensing technology in China.