The Role of Energy Storage Systems in Reducing Effect of Load Models on Frequency Dynamics and Large Disturbance Rotor Angle Stability

摘要

This paper analyzes the effect of load models on grid frequency dynamics and large disturbance rotor angle stability without, and with energy storage systems (ESS). The analysis also investigates the sensitivity of frequency support to the mode of deployment of ESS and its location when the penetration levels of renewable energy sources increase and inertia of the system reduces. The analysis shows that the provision of primary frequency support (PFR) by ESS significantly decreases the variation in frequency nadir and steady state frequency devtations due to load models. The analysis also illustrates that the location of ESS plays more critical role than the mode of deployment of ESS in improving the frequency response of the system when the proportion of RES becomes higher than synchronous generation. The large disturbance rotor angle stability analysis shows that not only critical fault clearing time (CCT) but also the number of generators exhibiting instability varies with load models. The results of the case studies show clearly that the presence of ESS in the network with primary frequency control has the potential to improve large disturbance stability of the network.