Optimization of Relay Protection Device Renovation Plan for East China Power Grid Using Deep Deterministic Policy Gradient (DDPG)

In this paper, a method for optimizing the retrofit scheme of relay protection devices in East China Power Grid based on Deep Deterministic Policy Gradient (DDPG) algorithm is proposed. By constructing a state evaluation model and life cycle management method, the timing and strategy of relay protection device retrofit are optimized by combining the DDPG algorithm. The experimental results show that the average trouble-free operation time of the modified equipment increased from 555 hours to $\mathbf{7 1 0}$ hours; the correct action rate increased from 89.83% to $94.83 \%$; the number of power outages was reduced from 5.3 to 3.3, and the duration of outages was reduced from 10.6 hours to 6.6 hours. In the conclusion of the above data, the DDPG optimization scheme can significantly improve the operational reliability of relay protection devices and the stability and security of the power grid.