Market-Driven Under Frequency Load Shedding Method in a Restructured Environment

Load shedding can be defined as the amount of load that must almost be instantly removed from a power system to maintain the remaining part of the system operational. Market-driven load shedding in restructured power system consider in this paper. This paper presents the design and implementation of a new method that consider optimal under frequency load shedding scheme in competitive electricity market. The proposed method includes two steps. In first step essential amount of load shedding is achieved to restitute the power system stability and put steady state frequency in allowable range after contingency occurring. Then in the second step technoeconomic function is presented in market-driven scheme, to specify an optimal load shedding amount for each loads. The proposed problem include maximum generating companies profits considering penalty cost of electricity power not supplied and minimizing congestion rent of branch in competitive electricity market. In order to solve multi objective function, a particle swarm optimization (PSO) is used to find the optimal value of load shedding. Generating output associated with the price of each generator, power output and price of dispatchable and sensitive loads are calculated through performing smart market procedure. The obtained results represent the advantageous of the proposed methodology in designing the optimal load shedding to restore system frequency in a restructured environment through technoeconomic procedure.