Characterisation & Optimisation of Battery Banks in Substations (COBBS)

Completed

Other Power and Storage Technologies(Electricity transmission and distribution)
Other Power and Storage Technologies(Energy storage)

Applied Research and Development

ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering)

Not Cross-cutting

Project Contact
National Grid Electricity Transmission

Network Innovation Allowance

Ofgem

01 July 2023

31 March 2026

ENA months

£592,069

Power

London

Network Innovation Allowance

Project Contact, National Grid Electricity Transmission

ata collection surveys and investigations will be conducted at various NGET substation sites. Testing within the high voltage laboratories at Cardiff University will make use of existing generators and recording instrumentation and laboratory general facilities. The current and voltage measurements will require suitable transducer purchases for the specialist condition monitoring. In addition, computerised data acquisition equipment will be purchased. A possible solution to achieve sizing optimisation would be by utilizing tailored duty cycles based on the independently measured load demands of equipment at NGET"s substations. Expertise from the university will involve work on electrical testing & measurements, laboratory characterisation and battery technologies. Literature survey: Carry out a wider literature survey of DC battery usage in LV systems within transmission substations. Reviewing published literature and examining practice of battery usage on electrical networks in the UK and beyond will reveal any important aspects of battery bank practice that are worth noting going forward. Survey of battery usage on NGET network: Carry out survey of LV equipment connected to substation 110V & 48V DC systems which mainly feeds control and protection equipment through the use of substation batteries on the grid. Work with National Grid engineers to survey and develop an inventory of types of batteries and their typical use on NGET grid network. The survey will also include existing practice for charge/discharge and control of the battery banks. Any available measurement data will be collected and analysed. Development of sensors & transducers: Develop or purchase and install suitable measurement sensors and transducers to monitor DC loads and battery charge/discharge profiles on both centralised and distributed dc systems. Emphasis will be on measurement of current and voltage under both steady state and transient operating conditions. This is a core design, test and calibrate task within the project for both short- and long-term measurements and determination of battery utilisation profiles. It is expected that multiple measurements will be developed and deployed to allow measurement at the battery input/output as well as the direct feed from the alternating current (AC) system and the consumption at the DC energised LV equipment.  Deployment of online condition monitoring: Develop an online condition monitoring system and computerised data acquisition and analysis to obtain short to long-term load profiles and parameters of DC equipment for all LV types of DC equipment tied to the system. It is expected to use the measurement equipment developed in sensors & transducers task above. Explore optimisation of battery usage: Using the characterisation findings above from condition monitoring measurements (transient & steady state standing load), explore the suitability of current Institute of Electrical and Electronics Engineers (IEEE) sizing methodology used by suppliers, and assess possibility of battery sizing optimization.  Application of existing standards for DC standby systems: Survey existing practices used by National Grid in relation to DC standby systems as well as any related standards e.g., International Electrotechnical Commission (IEC) & IEEE standards connected to stationary applications.  Feasibility of new battery chemistries: Exploiting the new knowledge gained from the current battery usage profiles, explore use of battery chemistries not yet used by National Grid and assess any potential advantages and disadvantages for substation standby applications. This should consider whole life value parameters (installation and maintenance requirements, decommissioning) as well as performance aspects.  Standard and industry practice revision: With the findings of this work, explore revision of maintenance standards where applicable. The project objectives can be summarised as to: Understand current battery banks world best practise through a wide literature survey including a survey of battery usage on NGET networkMonitor direct current loads and battery discharge profiles on both centralised and distributed systems to measure current and voltage performance under different steady state or transient operating conditionsAcquire short-term and long-term load profiles through online condition monitoring and computerised data acquisitionConsider standard battery sizing methodologies and possibilities for optimisationReview existing standards for DC standby systemsInvestigate and recommend use of new of battery chemistries not yet used by National Grid and assess any potential benefits Review applicable maintenance standards and industry practiseSupport the energy transition and deliver net benefit through innovation in low voltage direct current systems.

Substation battery banks (SBB) in electrical substations participate in black start recovery processes and provide essential back-up power supply for protection, control, telecommunications, and lighting. With stringent limitations on space and increasing requirements for safety and reliability, potential battery sizing optimisation opportunities may be possible to enable reliable, secure, space, time and cost-effective substation energy storage. Battery efficiency with optimal use supports the energy system transition by supporting evolving substation loads requiring appropriate scaling design that avoids costs in either oversizing initial banks or reinstalling entirely new banks. This project considers existing and future battery banks improvements to best practice, better chemistries, and online monitoring techniques with expected benefits in reducing carbon footprint and maintenance costs whilst informing correct & adaptive battery sizing.

02/10/24