Flexible reactive power management using PV inverter overrating capabilities and fixed capacitor

The rapid growth of photovoltaic resources is an opportunity for reactive power management of low voltage distribution grids. This study presents an optimal planning framework for reactive power management considering the photovoltaic inverter capability and fixed capacitor. In this regard, the inverter capacity along with location and number of the fixed capacitors are simultaneously determined to minimize the investment of reactive power compensation. To be more realistic, investment, maintenance and operation costs of compensation devices as well as lifetime and oversizing of the inverter are considered in the objective function. In this paper, accurate AC load flow equations along with technical constraints are integrated into a mixed-integer second-order conic programming model. The suggested methodology can be optimally done using commercial solvers to satisfy all technical constraints such as voltage limits and capacity of distribution branches at any penetration level of photovoltaic resources. Two case studies are implemented and simulated using MATLAB software in order to show the analysis and effectiveness of the proposed reactive power management. The comparison of the suggested technique with the conventional methods confirms the considerable reduction of investment and energy losses in a real low voltage distribution grids (400 volt).