Augmenting DER hosting capacity of distribution grids through local energy markets and dynamic phase switching

Abstract

The limited capacity of distribution grids for hosting renewable generation is one of the main challenges towards the energy transition. Local energy markets, enabling direct exchange of energy between prosumers, help to integrate the growing number of residential photovoltaic panels by scheduling flexible demand for balancing renewable energy locally. Nevertheless, existing scheduling mechanisms do not take into account the phases to which households are connected, increasing network unbalance and favoring bigger voltage rises/drops and higher losses. In this paper, we reduce network unbalance by leveraging market transactions information to dynamically allocate houses to phases using solid state switches. We propose cost effective mechanisms for the selection of households to switch and for their optimal allocation to phases. Using load flow analysis we show that only 6% of houses in our case studies need to be equipped with dynamic switches to counteract the negative impact of local energy markets while maintaining all the benefits. Combining local energy markets and dynamic phase switching we improve both overall load balancing and network unbalance, effectively augmenting DER hosting capacity of distribution grids.

Real-time enforcement of local energy market transactions respecting distribution grid constraints

“…Procedure and system scenario The simulation of the real-time control mechanism relies on local energy market results and on an allocation of households to phases updated by a DPS mechanism. Those two additional mechanisms are simulated following the procedures described in [5] and [15] respectively.…”

“…We need to ensure the flows across phases are as evenly distributed as possible in order to improve RTC mechanism performance, which is not aimed at balancing load across phases. We assume the operator is capable of deploying solid state switches in a subset of households and of controlling dynamically their allocation to phases as described in [15]. This functionality is complementary to the RTC mechanism.…”

Impact of Local Energy Markets Integration in Power Systems Layer: A Comprehensive Review

“…Imbalance across different phases [49], [50], [51] Affected by prosumers' trading behaviour Introduction of control mechanism does not have negative on market mechanism outcome [51] System power peak…”

“…Network imbalance between phases can lead to bigger voltage rises and higher losses. Horta et al [50] presented a method to minimize the negative impact of market participants, which are considered to have the highest impact on voltage unbalance due to their DER installation. This is ensured by dynamic phase switching by the system operator.…”

Improving Operational Feasibility of Low-voltage Distribution Network by Phase-switching Devices

“…To mitigate the unbalance issue, one cost-efficient choice is to employ phase-switching device (PSD) to change the phase that each residential customer is connected depending on the operational state of the LVDN [2,6]. As deploying PSD provides more options to operate the LVDN, the corresponding TUPF may become solvable due to the enlarged feasible region, thus improving the operational feasibility.…”