Optimal Control Methods for Photovoltaic Enabled Grid With Abnormal Power Loads

This paper proposes two different control approaches to minimize the power loss subject to voltage constraints when photovoltaic (PV) cells are connected to the grid subject to abnormal (unexpected and extremely high) power loads. A dynamic load model is integrated with the DistFlow equations to describe the transient behavior of the real/reactive power, voltage, and loads. Based on this model, the proposed controllers utilize PV inverters to optimize performances of the grid by absorbing/injecting the reactive power. These controllers are particularly efficient to handle unexpected abnormal power loads. For demonstrations, a bidirectional, single branch distribution circuit with extremely high power load is used to test and compare our controllers with existing approaches, including the volt-ampere reactive control scheme specified by the IEEE Standard 1547 and adaptive method. The results show that our controllers indeed reduce the power loss compared with other methods and keep the voltage within the desired range.