Robust Centralized-local Control Strategy of Distributed Photovoltaic Inverter Considering Short-time Fluctuation

In allusion to the problem that the centralized control of photovoltaic inverter takes into account the short-term fluctuations of source and load deficiently, a robust centralized-local control strategy was proposed. Firstly, taking minimizing network loss and light rejection as an object, centralized active and reactive power control model was established; In view of the voltage out of limit and power flow fluctuation caused by the short-term fluctuation in the control interval, a three parameter centralized-local control model of reactive power output-active power reduction-slope parameter was proposed based on the centralized control results. Secondly, the interval model was used to model short-term fluctuations, and the robust optimization model of local control strategy was established to minimize the voltage deviation in extreme fluctuation scenarios. Finally, solution method of control strategy based on second-order cone programming and sensitivity analysis was proposed. The validity of proposed model was verified by a numerical example, and the influence of fluctuation, permeability and inverter capacity on the control was analyzed to improve the operation safety and economy of the active distribution system.