With the construction and development of the new generation of power system (thereafter, it is displaced with PS), intelligent power equipment is more widely used and higher requirements for the flexibility, controllability and safety of PS emerge. This article focused on the key technologies of equipment operation and maintenance (O&M) in the PS, aiming to improve the challenges faced by traditional PS through new energy power and intelligent PS. The article studied the development of new PS, analyzed intelligent PS from the perspectives of intelligent maintenance, online fault diagnosis and status monitoring and evaluation, compared the capacity of new energy equipment and simulated the wind PS simulation structure diagram. Setting the Longyangxia Hydropower Station as an instance, it explored the complementarity between solar and hydro energy in the hydropower station. By studying the service life of transformers in 50 PS of Longyangxia Hydropower Station, it was found that amorphous alloys and silicon steel were relatively excellent and a total of 8 rounds of power generation equipment in the PS passed the safety assessment. The article proposed a long-term maintenance research method for the key technologies of equipment O&M in the new PS, achieving precise management and efficient maintenance of equipment and ensuring safe and reliable operation of equipment under complex working conditions.