Analysis of Transmission Congestion Using Power-Flow Solutions

Transmission congestion has become a new challenge in an open-access environment of electric transmission networks. In today's world, electric power networks have been so much loaded that such a case has never been observed before. Due to overloading, transmission lines of the networks are congested. Under these circumstances, management of transmission congestion is a crucial task for successful operation of power systems. Our specific problem is to detect load centers or cities that are not congested for power transmission from a specific power plant such as newly-built wind farms and small size hydro dams. In this study, we analyze transmission congestion using power-flow solutions for various load and generation levels. Under the condition that additional generation is supplied and the corresponding load is demanded, we run the power-flow program that we have developed. After obtaining the base case solution of the power flow, we select a candidate bus from load buses to apply incremental changes in real and reactive power. In order to assess the real and reactive power capacities of the candidate bus, we plot the P-V curve and the Q-V curve for the candidate bus. As a result of this process, we have the real and reactive power capacities of the candidate bus and information about the congested parts of the power network. Therefore, we provide such information for power utilities to manage power efficiently and power marketers to sell power economically.