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As residential PV generation penetrates in the low‐voltage distribution network (LVDN), the unbalance issue may be intensified due to the asymmetry of generations/loads in different phases. Phase‐reconfiguration device (PRD), which can reconfigure connected phases of residential customers, provides an effective method to address this issue. Noting that although the benefit brought by PRDs can vary if they are placed at different locations in the network, little literature has been reported on this topic. To bridge the research gap, this paper presents a novel method to optimally place PRDs in an LVDN aiming at minimizing the power unbalance running through the distribution transformer. The problem considers both installation, operational constraints, and boils down to a challenging mixed‐integer non‐convex programming problem, which is then reformulated as an efficient solvable mixed‐integer linear programming problem. Moreover, operational constraints are relaxed with slack variables penalized in the objective function, which makes sure a feasible solution is always available without or with minimal operational violations. Case studies based on a modified IEEE system and a practical system in Australia demonstrate that an efficient strategy can be provided to address the unbalance issue while improving the network's power supply qualities. [ABSTRACT FROM AUTHOR]

As rooftop solar PVs installed by residential customers penetrate in low voltage distribution network (LVDN), some issues, e.g. over/under voltage and unbalances, which may undermine the network's operational performance, need to be adequately addressed. To mitigate unbalances in LVDN, phase-switching devices (PSDs) and static var compensator (SVC) are two equipment that is cost-effective and efficient. However, most existing research on operating PSDs is based on inflexible heuristic algorithms or without considering the network formulation, which may lead to strategies that violate operational requirements. Moreover, few pieces of literature have been reported on mitigating unbalances in LVDN via SVC and PSDs together. This paper formulates the decision-making process as a mixed-integer non-convex programming (MINCP) problem after developing an SVC model for dispatch purpose. Compared with existing work, the proposed method aims at minimizing current unbalance based on their phasor values and takes the network's operational requirements into account. To efficiently solve the challenging problem, the MINCP is reformulated as a mixed-integer second order-cone programming (MISOCP) problem based on either exact reformulations or accurate approximations, making it possible to employ efficient off-the-shelf solvers. Simulations based on two modified IEEE systems and a practical Australian LVDN demonstrates the efficiency of the proposed method in mitigating unbalances in LVDN. [ABSTRACT FROM AUTHOR]

Dwindling fossil fuel resources and concern of climate change resulting from the burning of fossil fuels have led to significant development of renewable energy in many countries. While renewable energy takes many forms, solar and wind resources are being harvested in commercial scale in many parts of the world. Government incentives such as renewable energy certificates and feed‐in tariffs have contributed to the rapid uptake. In Australia many residential customers have taken up roof‐top photo‐voltaic (PV) systems. These residential PV generations are embedded in the low voltage (LV) networks that are not designed to take intermittent, two‐way flow of electricity. Utility engineers are faced with the challenge of a legacy electricity distribution network to connect increasing amount of embedded PV generation. This study focuses on two aspects of the technical limitation – steady state voltage delivery and phase imbalance – and proposes how the technical limitations can be improved by optimising the existing voltage control schemes, the balancing of loads and generations between the supply phases, and finally the adoption of smart grid methodologies. This prioritised approach provides a cost effective means of addressing the impact of embedded PV generation. The proposed method is verified by computer simulation on a realistic LV distribution network in the state of Victoria, Australia. [ABSTRACT FROM AUTHOR]