Aggregated Effect of Active Distribution System on Available Transfer Capability Using Multi-Agent System Based ITD Framework

Proliferation of renewable energy sources both at transmission and distribution levels causes uncertainties in electrical parameters of the existing system. It would subsequently affect the assessed available transfer capability (ATC) for the system. Further, an impending shift in modes of transportation from conventional to electric vehicles (EVs) also poses a challenge as they would act as potential source/sink depending upon psycho-economic factors. In an active distribution system (ADS), the distribution system operator employs tools such as volt-VAR optimization (VVO) to reduce the economics of operation. Attempts to assess the overall effect of the ADS, considering the presence of EVs, and VVO on ATC of the system have been investigated in this article. A framework for assessing the impact of ADS on a transmission system (TS) has been employed to emulate IEEE 24-bus reliability test system (RTS) at transmission level and IEEE 123-bus system at distribution level. Two indices ATCEfactor and ATCVRfactor have been introduced for assessing the impact of ADS on ATC. It is observed that the presence of distributed energy resources (DERs) and proper utilization of Volt-VAR techniques have potentials of increasing the ATC of the system.