The clearing strategy of primary frequency control ancillary services market from the point of view ISO in the presence of synchronous generations and virtual power plants based on responsive loads

Since the increase in penetration of renewable energy sources connected to the system reduces the inertia of power systems, the penetration of these sources leads to increase in the requirements of primary frequency control (PFC) services. Fortunately, with the expansion of network intelligence platforms, responsive loads (RL) can be effectively useful in ancillary services in the near future and can be used like traditional power plants. Since these equipment have a high rate of change of status, if they are visible in the market by aggregating (with virtual power plant (VPP)), they can compete with synchronous generations (SG). Because the response speed of the participants in the market can affect the decision independent system operator (ISO) in determining the winning units, therefore in this article, we have proposed a market framework to create competition between SGs and VPPs in providing ancillary services. In the proposed framework, ISO minimizes the weighted sum of power purchase costs from VPPs and SGs. The proposed weighting coefficients express the response speed of each unit. In fact, the desired objective function is affected by two terms, cost and speed. The presented model has been simulated on a test system including four SGs units and one VPP unit in matrix laboratory (MATLAB) software and checked under five different scenarios. The comparison of the obtained results indicates an increase in the possibility of accepting units with a smaller weighting factor and a higher response speed (the meaning of accepting units are market players, i.e. SGs and VPPs).