Overcoming the power factor apparent degradation of loads fed by photovoltaic distributed generators

Abstract Decentralised grid-connected photovoltaic systems (DGCPS) have proved to be an alternative to traditional electricity generation because they have introduced advantages to power systems, such as reducing electrical losses, relieving transmission and distribution lines, and provisioning ancillary services. Despite all these benefits, a new class of problem concerning DGCPS has been reported in the literature. From the utilities’ point of view, the installation of a DGCPS may lead to an apparent degradation of the load power factor. This effect does not have physical causes, i.e. equipment malfunction or overuse of reactive power by the load, although it may lead to reactive power excess charging (RPEC). Since these charges could lengthen the payback of PV installations, this paper aims to assess three strategies to tackle this issue. The first strategy, which has demonstrated to be best for prosumers, is a new regulatory scheme for reactive power monitoring in consumer units with DGCPS. The other two solutions are classical approaches based on reactive power compensation from PV inverters or capacitor banks. For these two last solutions, this paper provides an innovative and optimized way of operation that can adjust the load power factor measured by the utility in real-time, minimizing economic losses.

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