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        • Aurora works across a wide range of traditional power generation systems, from small CHP units up to large industrial power generation facilities. We have extensive experience in considering synchronous generators fault contribution into the network, as well as considering issues such as dynamic response and transient stability of synchronous generators.

        • Renewables & Energy Storage
        • Aurora provides a range of services to the Renewables and Battery Energy Storage Systems industries, and can provide advice on analysis on greenfield developments or integration into existing brownfield industrial facilities. We specialise in providing grid simulation and G99 compliance studies to support renewable connections to the UK network, and other European networks.

        • Transmission & Distribution
        • Aurora has extensive experience in the transmission and distribution sector, dealing with private 11kV and 33kV networks, iDNOs and DNOs and National Grid, for a variety of different design and analysis applications.

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        • Aurora has extensive experience in the Oil & Gas industry, and has undertaken a wide range of design activities, concept studies and simulation studies to support many large international EPC companies and service companies.

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        • Aurora works in light and heavy industry providing a range of services to help plant owners analyse and understand their networks, identify weak spots, providing guidance on system loadings, fault levels, earthing, protection coordination and arc flash.

        • Data Centres
        • Aurora has worked on a number of large data centres, providing a range of services to support existing specialist companies in this area, such as system analysis for fault levels, harmonic analysis, protection coordination and arc flash analysis.

        • Building Services
        • Aurora works in Building Services industry to support multiple M&E contractors in development of the HV aspects of their design, or integration of renewable technologies like roof top solar.  Services include system analysis for fault levels, harmonic analysis, protection coordination and arc flash analysis.

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        • Aurora has extensive experience in the water industry and has worked fs, identify weak spots, providing guidance on system loadings, fault levels, protection coordination, motor starting earthing and arc flash. We also have extensive experience in helping water companies integrating renewalbe power and battery storge technologies into their sites.

        • Power System Analysis
        • Load flow, fault analysis, P28/2 voltage disturbance including flicker and transformer inrush, G5.5 Harmonics, G99 Grid studies, protection coordination, arc flash, dynamic and transient studies and electromagnetic transients.

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        • Concept selection, contingency analysis, switchgear and transformer specification, SLD preparation, cable sizing, UPS sizing, substation layouts, protection scheme design, wiring modifications for EPC and M&E companies.

        • Power System Earthing
        • Earth potential rise (EPR) calculations and touch and step voltage calculations with either CDEGS or XGSLab, earthing layouts, soil resistivity testing, fall of potential tests, earthing inspections and resistance testing.

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        • Concept development and decarbonisation strategies, preparations of G99 and National Grid connection applications, review of ICP and vendor proposals, due diligence checks and client representative and failure investigations.

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P28/2 – Voltage Fluctuation Studies

P28/2 or voltage fluctuation studies are applicable to a wide variety of plants and a key regulatory requirement of DNOs, to ensure that a private network does not adversely affect the public network by creating problems of voltage flicker, or problems for voltage regulation.

The studies are primarily carried out for generation projects and battery storage projects to check the Step Voltage Change (SVC) associated with generation trips and the Rapid Voltage Change (RVC) associated with transformer energisation and battery storage unit power swings. However, they are also applicable to sites with large fluctuating loads such as large pumps and compressors, arc furnaces, winders, and so on.

Where things get really interesting is for battery energy storage projects. These are a new (for DNOs) type of project that are making many DNOs nervous. Traditionally BESS units were assessed considering power ramps from full import to full export, and full export to full import over a 1s duration – however it is becoming clear that such an approach is really a bit too simplistic. At Aurora we developed a standalone controller which can be used to replicate any of the standard DC / DR / DM services and then developed a method to generate a typical frequency disturbance profile based on NG ESO historical data. We will do a more detailed post on that next week, but its some clever and interesting stuff.

  • Transformer Energisation
  • Step Voltage Change (SVC)
  • Rapid Voltage Change (RVC)
  • Battery Storage Power Ramps
  • Battery Storage DC/DR/DM response
  • Large Load step and change factors
  • Flicker (Pst & Plt)

Aurora can carry out a detailed P28/2 voltage fluctuation assessment for any type of site, using either DIgSILENT Powerfactory or ETAP. If you want to know more – please get in touch