REACTIVE POWER COMPENSATION IN CONSUMER UNITS WITH GRID-CONNECTED PHOTOVOLTAIC SYSTEMS
DOI:
https://doi.org/10.59627/cbens.2016.2037Keywords:
Solar Energy, Grid-Connected Photovoltaic Systems, Reactive Power CompensationAbstract
According to the current rules in Brazil, the power factor measured by the electricity utility and used for billing a consumer unit (UC) of Group A (supply voltage less than 2.3 kV) is calculated from the flows of active and reactive power exchanged between UC and that the grid. Due to this form of measurement, when the UC has part of its demand for active power supplied by a generating plant installed on site and its demand for reactive power is supplied by the power grid, there will be an apparent deterioration in the power factor in relation to the situation where the two demands (active and reactive) are supplied exclusively by the utility. In this condition, depending on the load profile (inductive or capacitive) and the corresponding time, there may be charges for the reactive power excess that would not occur without the presence of the self generation plant. In respect of a Photovoltaic Generation Plant (UFV), the identified problem specifically occurs during the day and when the load has an inductive profile. In this sense, a possible mitigating action, which was tested in this work, is to use the own inverter of the PV system to meet the UC demand for reactive power, eliminating the need of purchasing it from the grid. The results indicate that this is a valid strategy to avoid the reactive power excess charges without affecting system performance and without significantly changing the voltage at the connection point.
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References
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