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  • Writer's pictureIlhan Seven

Flexible Plant Manager: A Holistic BESS Control Solution with Built-in Market Access

Energy storage is essential in the energy transition. However, using battery energy storage at a large scale is fairly new and the ways of working for the conventional power plants do not quite apply. It is a set of unique challenges for the different stakeholders in the industry:


  • Asset Owners / Managers need to use multiple providers for the overall control and management of a BESS plant, leading to use of multiple portals to gain full visibility and performance of an asset (e.g. BESS manufacturer portal, O&M portal and a Trader’s control/scheduling portal etc.)

  • BESS Integrators and Developers need to adapt their systems to different grid regulations around the world. This includes local and remote interfacing with the grid authorities. Site testing, commissioning and achieving grid compliance (e.g. UK G99) are costly and time consuming activities.

  • Operation and Maintenance Contractors are expected to take a proactive approach and provide minimum downtime for the plant. If a local SCADA server is deployed, they rely on this for monitoring and fault finding of Balance of Plant equipment (e.g. transformers, relays, breakers) and the BESS units. Even then, in-depth string and cell data may not be available.

  • Traders/Route to Market Providers have to be agile in the rapidly evolving market conditions. Control systems packaged with the BESS installations are slow to adopt these changes. Therefore a secondary layer of control is required which is usually achieved with a Route to Market Gateway.


The complex structure of BESS Management


Having been in the BESS route-to-market chain for more than 6 years and with more than 1.2 GW of battery storage under management, Kraken has encountered these challenges numerous times. Spotting the lack of a holistic approach to address these in the industry, our experienced team have put their efforts into developing an end-to-end control, management and market-access solution dedicated to grid scale battery storage systems.


  • On site is Kraken’s Flexible Plant Manager (FPM) - a combined site PPC (Power Plant Controller) and route-to-market access gateway. Built-in I/O capabilities provide monitoring and control for the Balance of Plant equipment. Enhanced telemetry capability can be added for in-depth string and cell level data visibility.

  • On the cloud side, our InfraFlex SaaS platform provides services including full asset visibility, control, optimization and market access.



Kraken’s combined solution for the overall complexities of BESS Management


What makes FPM different?


There is a clean responsibility split within the design of FPM. Our ever evolving market capabilities are performed by a modern application deployed on an industrial PC, fully agile in design to instruct a BESS in any new grid services that are within its electrical capabilities. The most stable logic for grid compliance and critical control (and least likely to change) is performed by PLC technology. This ensures safe and compliant operation of the BESS at all times.


In the chain of control, all commands sent to the BESS units or against the site eventually pass through the PLC logic. This ensures that the static and dynamic site limits as well as the individual asset capabilities are always respected. A watchdog mechanism ensures fail safe operation of the site in case of software upgrades or unexpected component failures within the route to market gateway.


Chain of control for the BESS Plant


FPM has built-in functions for closed loop active and reactive power control at the site boundary and multiple  reactive power control modes (constant Q, power factor or voltage support). In site control mode, smart distribution of power to the BESS units keeps the state of charge levels balanced at all times. Individual control of the BESS units for testing and balancing is also available.


The expandable I/O capabilities of FPM’s PLC platform enables interfacing with most balance of plant equipment (e.g.: transformers, relays, breakers, meters, other sensors and on site ancillary equipment). Operational information is relayed in near real time by the Gateway to the InfraFlex platform to provide visibility of the plant for operation and maintenance purposes. One of our ultimate targets is to enable predictive maintenance by using historical data and producing forecasts. Currently, any critical data captured from the site can be turned into an alert that is to be relayed to relevant parties.


Challenging the bulky on-site SCADA


Today’s BESS installations are usually designed to be unmanned during operation. For this reason, FPM challenges the old way of bulky, hard to reach on-site SCADA with operator desks and stations. It keeps to a cloud first approach by constantly relaying in near real time the operational data to the InfraFlex platform. However, having worked with O&M partners for many years we’ve observed that site engineers sometimes lack an overall site control interface. This requires them to visit each BESS container one by one to do a single command. To address this, FPM has an HMI (Human Machine Interface) screen to serve as a lightweight on site SCADA.


Human Machine Interface Screen


The HMI features an industrial high resolution touchscreen showing an overview of the BESS plant on the main page and subpages of individual BESS units. Site level active power and individual BESS state / active power output can be controlled by the user. Units requiring maintenance can be fully disabled from the HMI by a local operator. PLC diagnostics, statuses, alarm log, I/O visualisation and configuration are all available and features to support multi-users system access / control permissions.


Easing the site testing and commissioning


Battery Energy Storage Systems are treated like any other generation in the power grid and bound by the regulations of the local grid authorities. In the UK, power plants are assigned a class based on their size and the connection point to the grid. They then need to comply with either the regulations of EREC G99 or the Grid Code, including test activities (on top of the commissioning of the BESS and Balance of Plant equipment) that are costly and time consuming.


Two of the main things in these regulations are the mandatory frequency (LFSM & FSM) and voltage support. The plant needs to demonstrate capability for these at the grid connection point. Historically this involved bulky and costly injection equipment, manual commands and offline logging that usually relies on the in-built capability of the power meters. FPM changes  this approach with its internal Commissioning app..


The Commissioning app. is an on-demand tool that we’ve internally developed and is accessible via a connected local computer web browser through a dedicated engineer’s port. It allows initial configuration of all static active and reactive power limits, dynamic limits for schemes like Active Network Management (ANM) and reactive power control modes (disabled, constant rp, constant pf, voltage control).


Commissioning App Interface


The Commissioning App makes site testing simpler and easier for the commissioning engineers. It uses software injections to simulate the voltage and frequency, and has pre-programmed test sequences which can be run with the click of a button. Data logging is automatically started and the log file can be easily downloaded at the end of the test for further processing. As with the HMI’s capabilities, operational data is visualised and manual control available of the plant and individual BESS units.. 

Our plans with the Commissioning App are not over yet and we are keen to take it further by introducing automated analysis of the data post the tests, generating graphical results and composing test reports.


Where it all comes together: The InfraFlex Platform


Our InfraFlex SaaS platform is currently managing a large portfolio of energy assets, of which more than 1 GW are BESS installations. Through the platform, these BESS plants participate in energy trading, peak shaving, demand shifting and ancillary services (e.g. Dynamic Containment, Moderation and Regulation). A whole site or individual units can be scheduled “out of service” for maintenance or other non-operational activities.


Graphically represented BESS metrics with service history


The InfraFlex standard package provides advanced scheduling for any control mode, real-time whole asset visibility and 6-weeks historical data (e.g. SoC, available energy, available power etc.). The Enhanced Telemetry package provides deeper device level monitoring including string and cell level data where required. Any data taken from the site can be graphically visualised and alerting enabled for the most important data points. All data is accessible via cloud APIs.



Single Line Diagram view of the BESS site


InfraFlex dashboards provide SLD style holistic views of the BESS plant, including where available the status and health data from Balance of Plant equipment. Switchgear control and predictive maintenance are some of the things we’re looking to enable in the near future.


What’s next?


BESS suppliers may have their own EMS (Energy Management System) which delivers the control and monitoring requirements but falls short with regional grid compliance elements or balance of plant monitoring. PPC (Power Plant Controller) providers focus on grid obligations but may not have the market capabilities. Classical SCADA systems, if procured and installed, struggle with remote access and large amounts of data. And finally Route to Market Gateways would be looking after only the market participation. 


With InfraFlex and FPM we consolidate this complexity.


We aim to change the industry’s mindset and set the standard for end-to-end BESS control and management. We are on the lookout for like-minded asset owners / managers, developers/manufacturers, traders and other interested stakeholders in the battery storage ecosystem. Collaboration is key in transforming our energy systems for a better future!

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