Implementation of loadflow for networks with controllable network transformers

Traditional power system tools like loadflow are designed for systems with largely passive transmission and distribution assets. However, as the grid becomes smarter, more T&D assets are expected to be controllable. Tools such as loadflow and optimal power flow have to be modified to adapt to such “smart and controllable” grids. Controllable Network Transformers (CNTs) are low-cost power flow controllers that can be realized by augmenting an existing load tap changer by a direct AC-AC converter. This paper proposes a method for implementation of loadflow of networks with CNTs. The proposed method is applied to the IEEE 30 bus system and the results of the same are also presented.