Abstract
Soft open points (SOPs) are power electronic devices which can replace conventional normally open points in distribution networks. SOPs enable full control of active power flow between the interconnected feeders and can inject reactive power at each node to which they are connected. SOPs integrated with energy storage (ES) have been recently proposed to realize both spatial and temporal flexibility in active distribution networks. The flexibility provided by integrated ES-SOP devices will allow network operators to run their networks closer to their limits, but only if there is appropriate management of the uncertainty arising from demand and renewable generation. The only existing model of an ES-SOP uses nonconvex nonlinear equations, neglects uncertainty, and represents converter losses in an oversimplistic manner. This paper presents a robust mixed-integer convex model for the optimal scheduling of integrated ES-SOPs to ensure a zero probability of constraint violation. Losses of the subsystems comprising the ES-SOP are modeled using a proposed binary-polynomial model, enabling efficient scheduling of the energization state of subsystems to reduce no-load losses. The ES-SOP is considered in this paper to be owned by the network operator to: 1) manage power flow constraints, 2) minimize cost of losses, and 3) maximize arbitrage profit.
Highlights
SOFT OPEN POINTS (SOPs) are power electronic devices which provide a flexible interconnection between two or more feeders in electricity distribution networks [1]
This paper considers a system in which the second measure is used, and the focus is on optimal Energy storage (ES)-SOP scheduling and its impact on the cost of losses
This paper provides a method to optimize the schedule of a Distribution network operators (DNOs)-owned energy storage – soft open point (ES-SOP) device, which manages power flow to ensure that network constraints are violated with zero probability, whilst optimizing cost of losses and arbitrage profit attained through arbitrage
Summary
SOFT OPEN POINTS (SOPs) are power electronic devices which provide a flexible interconnection (in terms of active power) between two or more feeders in electricity distribution networks [1]. Energy storage (ES) systems can fulfil numerous functions in smart grids, including power flow management [4], and arbitrage [5]. Integrated energy storage – soft open point (ES-SOP) devices, which have been recently proposed in [7], offer a promising new solution which can provide both spatial (due to SOPs) and temporal (due to ES) flexibility to active distribution networks. This flexibility is offered at a reduced capital cost compared with installing an SOP and an ES system separately. This occurs as the SOP converters can be used to control charging/discharging of the ES, as shown in Fig. 1, without the need of additional converter(s) to interface the ES with two (or more) feeders of the network
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have