The demands placed on the modern substation are vast and growing. To adapt to the requirements of a rapidly changing power grid environment, medium-voltage (MV) substation operators are tasked with reducing costs, simplifying equipment maintenance and updates, accommodating increasing numbers of distributed energy resources (DERs) and improving renewable penetration levels into the grid, all while responding to constant and high demand.
While certainly no easy feat, the good news is that virtualization can help solve many of these challenges.
Substations are essentially the motherboard of the power industry, responsible for transforming voltage from high to low, or the reverse, to enable electricity to be transmitted safely and effectively to industrial and residential customers. It is therefore easy to see why substations are such a critical component of the energy transition.
Also, over the last five years, we have seen a radical evolution in the electricity grid as it increases its share of distributed energy resources (DERs), such as solar and wind energy, as part of the total energy generation mix. But while this transition may be net zero critical, the increase in DERs brings with it new challenges for substation operations ranging from voltage fluctuation and reverse power flow to overheating of components. This reinforces the need for investment in intelligence and resilience across the grid, especially in distribution networks where voltage stability is imperative. At the same time, distribution system operators (DSOs) remain under constant pressure to reduce capital expenditure and operating expenses generally.
Enter the growing case for virtualization as a way for DSOs to address these challenges, enabling the flexible and rapid deployment and evolution of substation applications from different vendors onto the same hardware by, essentially, creating virtual replicas.
Virtues of Virtualization
Virtualization – the concept of decoupling software from the underlying hardware – can help DSOs work more effectively and efficiently in many ways.
To understand how let’s consider the typical modern substation. In addition to the standard primary equipment, such as circuit breakers, busbars and switchgear, most substations now contain intelligent secondary equipment designed to allow automation and control. This can range from communication components and operator terminals through to SCADA (supervisory control and data acquisition) systems, running specific applications and working in isolation.
The result can be an operational minefield for the busy DSO, tasked with deploying and maintaining an ever-growing list of varied components. In some cases, because individual devices are usually vendor-specific it can mean modifications involve a specialist skill set to be outsourced at a cost. This requirement will continue to grow as more functionalities are added.
Through virtualization, where applications run in a ‘virtual’ environment abstracted from the underlying platform and isolated from other applications running on that platform, it is possible to deploy, execute, exchange and migrate almost independently of the platform. In most scenarios, this will involve installing one common hardware server at a substation, managed by a central operating system (OS) otherwise known as a hypervisor. From thereon in, different virtual machines (VMs) can be created for everything from protection and control through to automation and energy reporting, enabling DSOs to run what appear to be multiple machines, with multiple operating systems, on a single computer.
Fundamentally, this approach allows for a much smaller hardware footprint and reduces the need for vendor-specific skill sets and the amount of knowledge required to maintain the substation. It also enables most key activities to be performed remotely, in real-time, anywhere in the world, removing the need for a physical presence on site. As a result, virtualization can help to achieve high availability and resiliency at a reasonable cost.
What is equally appealing about a virtual approach is the ability to aggregate all the data from various applications and systems on separate VMs in the substation into one single user interface. For the busy DSO, the wide-reaching visibility afforded by this approach can empower better decision making in power quality, energy optimization, fault detection, asset management and more.
Cloudy Comparisons
Crucially though, despite many similarities it is important to note that the virtualization of substation technology is very different to cloud computing and brings with it a number of challenges.
While the cloud, for example, has ample and scalable computing, storage and networking resources, the resources available in substation devices are more modest. Unlike the cloud, the applications running on substation devices are of mixed criticality (safety-critical and non-safety-critical) and some applications may require specific hardware configurations – for example, support for the Precision Time Protocol in a network card. Moreover, many substation applications have special timing and high availability requirements that must be met during operation.
To ensure a seamless migration onto VMs, it is advisable to work with a specialist technology partner who will ensure a planned and methodical approach - reviewing existing assets, choosing the most suitable provider, preparing your teams. Otherwise, the risk is that configuration mistakes could compromise the real-time guarantees for the applications running in the VMs or containers.
Into Practice
Virtualization is a critical component of grid resilience and must play an important role in enabling DSOs to reduce complexity and work smarter, not harder.
In 2018 ABB introduced its SSC600 device, an innovative approach to protection and control in distribution networks in which all the protection and control functionality is centralized into one single device. Building on the success of the SSC600, ABB has now introduced SSC600 SW - the virtualized version of the SSC600 device.
An example of the benefits with centralized protection can be found in Finland, where our SSC600 has helped secure reliability and ensure asset optimization for Finnish utility, Parikkalan Valo.
As part of a major refurbishment of its Punkasalmi substation in Finland, Parikkalan Valo sought a solution to ensure safe and reliable power supply. As part of the remodeling of the substation, originally constructed in 1986, the utility wanted to be able to manage its electrical network and assets more efficiently; ensuring flexibility to meet future needs as requirements change.
Parikkalan Valo chose ABB’s centralized protection with SSC600, whereby all protection and control functions of the substation are centrally managed, operated and engineered in the same device. This means it is possible to update the entire protection and control functionality in one go, and there is no need to update an installed base consisting of protection devices of different types and ages.
Today, these benefits, and more, are also possible with virtualized protection and control.
A Virtual Reality
As we enter a new pace of digitalization, substation technology has followed. Today, most modern substations feature an increasing number of devices and automation components from multiple vendors – meaning more and more intelligent electronic devices are required. Maintaining and updating a myriad of proprietary devices can be expensive, timely and complex.
Undoubtedly, the radically evolving power grid will continue to add new pressure on DSOs. The emergence of virtualization as a route to better efficiencies, intelligence and resilience is inevitable, and now is the time to make the virtualized protection and control opportunity a firm reality for the future.
Henry Niveri ([email protected]) is Product Manager at ABB’s Distribution Solutions division. Currently based in Vaasa, Ostrobothnia, Finland, Henry specializes in centralized protection for digital offerings, engineering software and design architecture. He received his Master’s degree in computer science from Helsinki University of Technology in Espoo, Finland.
