Impact Analysis of Power Network Structure on Grid Strength

While the increasing penetration of renewable energy resources (RERs) into the electric power grid reduces greenhouse gas emissions, it may drive the grid's parts towards the “weak grid” conditions under which grid instability may occur due to small disturbances leading to voltage oscillations affecting the operation of renewable generation plants. To avoid such grid weak issues, one effective way is to reinforce the power grid by updating its components. A cost-effective grid reinforcement needs the information of critical components whose updates can significantly strengthen the power grid for renewable energy operation. In this paper, we study the identification of such critical components by the impact analysis of power network structure on grid strength. It is shown that the critical network components are shared by critical transmission paths between renewable energy resources and synchronous generation resources in a power grid. Moreover, critical transmission paths can be identified with the network structure information represented in node admittance matrix and node impedance matrix. Numerical results are demonstrated in the IEEE-9 bus and IEEE-39 bus systems.