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This paper presents a reactive power valuation method with regard to its effect on realization of MW transactions. The security constraint optimization model in which the objective function is maximization of transactions is solved by the genetic algorithm approach. The proposed scheme allocates a specific amount of MW transactions to each dynamic reactive power source. An index is introduced to derive VAr value from the calculated optimal parameters of power network. This index represents the system-wide effect of MVAr sources on MW transactions implementations. Application of proposed method has been illustrated using IEEE 30 and 14 bus test systems. Results are discussed and compared in... 

This paper presents a practical reactive power valuation method, for the purpose of the reactive power pricing, in which the VAr value is decomposed into two components. These components are basically different from those already employed in the literature. Using a security constrained optimization model, the proposed scheme allocates two specific amounts of MW transactions to each generator as a dynamic reactive power source. One of these allocated amounts represents the contribution of the VAr resource to the shipment of active power, while the other one represents the contribution to the protection of the system against voltage instability. The final VAr value is derived using the... 

The main focus of this paper is to find an upgrade plan for a microgrid. This plan includes system lines' upgrades, the place, and size of the new capacitors and DERs. As usual, the planning process is begun with the load forecasting. The main objectives include minimization of system upgrade cost, loss cost, loss cost in peak load, and finally demand cost. The last objective is realized here using the tap changer of the main station transformer and reactive power support of the sources available or planned for the future of the grid. This is always referred to as the conservation of voltage reduction. In order to consider the effects of bus voltages on the system demand, the ZIP model for... 

Reactive power dispatch in power systems is a complex combinatorial optimization problem involving nonlinear functions with multiple local minima and nonlinear constraints. In an open electricity market reactive power support is an ancillary service for real power transportation. From the viewpoint of ISO, this paper provides a dispatching reactive power model, based on optimal power flow, by which both the cost of procuring reactive power as auxiliary service and the losses of active power are minimized. In this paper the cost of reactive power support consists of two components: reactive power cost of generators and shunt capacitors. In addition an extremely powerful differential evolution...