A Statistical Evaluation of the Capability of Distributed Renewable Generator-Energy-Storage System in Providing Load Low-Voltage Ride-Through

The capability of a distributed renewable generator (DRG) in providing load low-voltage ride-through (LVRT) is examined. The harnessed renewable power, load demand, and the occurrences of low-voltage incidents are treated as random variables. The probability of successful load LVRT is assessed through the use of a copula function to quantify the stochastic dependency between the load and the renewable power. The analysis is then applied to the case of a series-connected photovoltaic DRG incorporated with capacitor energy storage, wherein the focus is to establish the analytical relationship between the probability of successful load LVRT and the rated power/energy capacities of the DRG capacitor. Determination of the optimal capacities of the DRG capacitor is achieved through maximization of the expected economic benefits obtained from the renewable energy harness and load LVRT minus the cost of the DRG capacitor.