Download Prof. Danny Sutanto  University of Wollongong, Australia

ECE – 590 I
POWER & ENERGY SYSTEMS SEMINAR
Monday, February 15, 2016, 4:00 – 5:00 p.m., Room 2017, ECEB
Grid Integration of Solar Photovoltaic (PV) Resources: Impact
Analysis and Mitigation Strategies
Prof. Danny Sutanto
University of Wollongong, Australia
Abstract
The deep penetration of distributed solar photovoltaic (PV) resources – rooftop solar PV – is becoming a reality for many
electricity distribution networks. The deepening PV penetration introduces new challenges that distribution networks need to
address. At times, the PV power output can exceed the load demand, and hence result in power flows from customers into
the grid. The direction of such flows is precisely opposite to that of power flows in conventional distribution grids without
distributed resources. Such reverse power flows create voltage rise problems in distribution grids, particularly in those with
weak radial topology. Passing clouds can cause PV power output to fluctuate because of the strong dependence on the
ambient solar irradiation. Such fluctuations cause the PV outputs to ramp-up or ramp-down at high rates, leading to voltage
fluctuations in the distribution grids. Another issue is the impacts of an unbalanced allocation of PV units at different phases
of a distribution feeder. Such situations can create a high neutral current, particularly during the solar noon periods, when
reverse power flows are at their peak. With neutral grounding resistance, the resulting high neutral currents may produce
considerable neutral potential.
Due to these impacts of deepening PV integration, distribution utilities impose limits on the capacity of rooftop installations
in order to ensure no violations of power quality and system security limits. In Australia, some utilities impose PV hosting
limits on PV unit size to be 3.5 to 5 kW per phase per residential connection and other utilities imposing limits in terms of the
infrastructure loading level not to exceed 30% of low voltage feeder capacity or 20% of zone substation capacity. Limits on
the PV penetration level, however, go against the thrust of the Australian Government’s Renewable Energy Target.
Therefore, a comprehensive analysis of PV impacts is required and the formulation of new mitigation approaches is needed
to enable deepening the PV penetration in the distribution grids. This presentation discusses in detail the nature of the
impacts of deeper penetrations of rooftop solar photovoltaic (PV) units in low voltage distribution networks on the grid
operations at both at the low and medium voltage levels. The mitigation strategies based on the deployment of integrated
PV and energy storage systems are presented, as well as the power electronic converters required for such a deployment.
Biography
Danny Sutanto obtained his BEng (Hons) and PhD from the University of Western Australia in 1978 and 1981, respectively.
He joined GEC Australia upon graduation and in 1982 he returned to academia and worked as a faculty member first at the
University of New South Wales and later at Hong Kong Polytechnic University, where he became Professor of Electrical
Engineering. At present, he is Professor of Power Engineering at the University of Wollongong, Australia. His research
interests include power system planning, analysis and harmonics, distributed generation, smart grid and battery energy
storage systems. He is active in IEEE and serves as the IEEE IAS Region 10 Area Chair. He has published more than 400
papers with over 95 papers in refereed international journals.