With the rapid development of the power grid

the importance of transmission system maintenance has received more and more attentions. This paper investigates the transmission system short-term maintenance strategies on standpoint of the whole transmission system. At first

components to be maintained are selected by equipment monitoring technology. As it is difficult to acquire component’s sensitivity on system reliability by disconnection analysis

this paper proposes the affected electrical quantity to evaluate the equipment importance level

which can improve computational efficiency. The optimal maintenance sequence is formed accordingly. Then the transmission system optimized maintenance model based on equal-risk theory is given referring to generator maintenance strategies. The model has taken the maximum reduction of load shed risk as the objective function. Reliability index variation during the maintenance period has been taken as the key parameter

while dynamic changes of equipment failure rate after maintenance

labor resource and budget constraints have been also taken into consideration. Finally

heuristic algorithm is employed to solve the proposed model. Case studies testify the feasibility and validity of this model.