Field Trial of Coordinated Control of PV and Energy Storage Units and Analysis of Power Quality Measurements

Abstract

Trends support low voltage distribution networks will soon experience significant uptake of customer-owned low-carbon technology (LCT) devices especially rooftop photovoltaics (PVs) and small-scale energy storage (SSES) systems. This paradigm shift will introduce some significant challenges in modern distribution network planning and operations owing to the temporal nature of modern demand. Therefore, it became relevant to investigate the UK low voltage (LV) network operations considering high uptake of PVs and SSESs through both field measurements and desktop studies. The aim was to validate through field trials, the flexibility benefits of peak demand reduction and reverse power flow mitigation through smart control of customer-owned SSESs. It was shown that peak demand of up to 60% could be achieved in UK distribution network through the smart control of these devices. In tandem with the demand reduction, the study revealed that type-tested SSES power interface units do not pose significant power quality risks even for 100% customer penetration. INDEX TERMS Ancillary services, coordinated control, distribution networks, low carbon technology, low voltage, photovoltaics, power quality, small-scale energy storage systems.

Data‐driven robust extended computer‐aided harmonic power flow analysis

“…Indeed, the report by CIGRE [30, 31] clearly reveal that harmonic interactions – ‘auto’ and ‘cross’ sensitivities do exist. The field measurements [8] conducted by the same authors also confirm this.…”

“…The high uptake of power electronic‐based loads in electricity distribution systems has necessitated the development of harmonic assessment tools and their improved versions in recent times [1–6]. Some of the methods have been extended to study the network operating conditions in the presence of harmonic pollutions [7, 8].…”

“…Harmonic power flows with the aim to overcome the described challenges have been attempted by other researchers. However, as noted in the literature, much attention has been devoted to the low‐voltage (LV) networks [8, 21, 22] and the transmission levels [4, 19, 23]. According to [21], only few studies have focussed on the MV level of distribution systems.…”

“…Such data are yet to be fully mined. Moreover, [8], has demonstrated that although a particular harmonic producing device (or the cluster of the same devices) might not pose significant risk to the network, the interactions between several types of NLLs are worth investigating. Such interactions can only be fully captured through measurements at different operating instances of the non‐linear devices.…”

Integrated Algorithm for Selecting the Location and Control of Energy Storage Units to Improve the Voltage Level in Distribution Grids

“…ESU, through the possibility of storing energy in them, can contribute to the elimination of the negative impact of stochastic variability of power generated by RES [5][6][7]. As a consequence, they can reduce voltage problems by balancing the active and reactive power production and demand, as well as decrease the grid load peaks, while reducing power losses and eliminating overload of transmission elements [8,9]. However, the cost associated with the installation of ESU remains high.…”