Microgrids (MGs) with high penetration of distributed generators may cause congestion in the distribution network during operation. To address this issue

this paper proposes a two-time-scale congestion management scheme for multiple MGs integrated distribution networks. Day-ahead hourly-scale dynamic congestion management (DCM) is formulated as a constrained optimization problem

which can be solved by utilizing the proposed alternating iterative method

with the privacy of both the distribution network and MGs being preserved. The sub-hourly-scale contract energy tracking aims at fully utilizing the controllable resources of the MGs to minimize the difference of the contract and actual exchanged energy between the MG and distribution network. Through coordination of the proposed two timescales of management schemes

the MGs integrated distribution networks can operate economically while avoiding the probable congestion predicament with high penetration of renewable energy. Simulation studies with a 13-bus system MGs integrated distribution network demonstrated this proposed approach is effective to manage the congestion problem in the distribution network

while the energy tracking approach can improve the welfare of the MGs engaged in energy contracts execution.