There are nearly 6,700 Symphony distributed control systems installed in plants around the world, which makes it one of the most widely deployed process automation systems around. The Symphony Plus family launched in 2011 is ABB’s automation solution for power generation and water networks, and continues to be widely used in process industries.
The Symphony Plus SD Series portfolio was launched in 2012 and enhanced in 2014 and 2015 to broaden the Symphony portfolio to meet new challenges in conventional and renewable power plants and water networks, focusing on distributed applications and SCADA architectures.
The power generation landscape has been changing dramatically in recent years, evolving from traditional thermal and large hydro installations, which mostly required a DCS automation architecture for a large power plant in a single location. Automation monitored and controlled processes through a local area network-based architecture, using proprietary protocols over well protected networks.
Increasing use of alternative generation sources such as solar photovoltaic, concentrated solar power systems, wind and biomass are spreading the
power generation process over a very large area. Distributed installations can still generate hundreds of megawatts (MW) of power, but instead of doing it in a square kilometer of space, they may do it over hundreds or even thousands of square kilometers.
From localized automation to distributed control
In these cases the traditional automation architecture based on small local areas of control no longer work. Distributed generation still needs the processing power of traditional DCS, but delivered by a large number of intelligent devices, like smaller controller or remote terminal units (RTU) spread over a very wide area. All of these components must exchange information with a remote control center where operators can monitor and take action when needed. In many cases, distributed devices may also need to communicate with each other to coordinate and synchronize
the execution of specific control and supervisory tasks.
This means automation in the power generation sector is moving beyond the challenge of controlling a large process in a small area, with large amounts of data generated locally at high speed, to the challenge of networking together a large number of data sources connected over an open and less reliable and secure network infrastructure.
Water automation and renewable generation is all about SCADA
The water networks industry and renewable power generation have very similar control challenges, and the evolution of the Symphony Plus control
architecture serves both applications equally well.
Water network automation mostly applies to water transmission and distribution networks - big pipelines that carry water over long distances and branch lines piping it to residential customers. District heating, from the automation perspective, is very similar to water distribution.
These types of applications are basically networks of pipelines and pumping stations. In the case of transmission networks, pumping stations are large installations, each one comparable to an individual plant. In district heating and water distribution networks, a large number of much smaller pumps manage the steam or water flow in the pipelines. The equipment control demands are different in the two scenarios, with large pumping stations requiring a small but complete DCS as opposed to the small distribution pumps being controlled by a local compact control unit. In both cases, however, the distributed nature of the application will require the water network automation solution to deliver remote supervision and control and data acquisition over long distances. This is the definition of a SCADA application.
Compare water network scenarios with renewable power generation applications, like solar fields and wind farms, and the similarities are immediately apparent: in both cases, pieces of equipment with limited automation needs are distributed geographically, and need to exchange data with a control center, and occasionally between themselves.
Traditional components, designed to address high processing power demand such as the flagship SD Series HPC800 controller, remain in ABB’s Symphony Plus portfolio to serve conventional power generation and process industry demands, but a very powerful controller is not the right answer for the challenge of distributed systems.
ABB therefore introduced a scaleddown controller, the SD Series SPC700 controller, a compact solution which, in addition to delivering performances suitable for the distribution of processing power, is perfectly compatible with the HPC800 and can be deployed in harsh environments with higher ambient temperatures and in the presence of corrosive agents.
SCADA: Secure, reliable and timely communication is essential
Communication is probably the greatest challenge of distributed power generation control systems. They must ensure data is moving over long distances, and is readily available to operators who, in the event of an emergency, will have to be able to make decisions and take immediate actions, such as blocking water supply from a polluted well.
While, in traditional power generation, DCS normally uses proprietary protocols that bring together devices belonging to the same family, renewable power and water automation systems are very frequently built up by bringing together pre-existing equipment and instrumentation
from multiple suppliers.
As a consequence, there is huge demand for open communication solutions that enable Symphony Plus to integrate into a single platform data from very diverse sources, from meters to remote terminal units or, in the case of water networks, analytic devices that provide data on water quality.
Addressing that challenge, ABB has developed a new family of Symphony Plus communication interfaces ideal for distributed systems. These modules can bring into the Symphony Plus platform data coming from any intelligent source, so the application owner has instant access to data from any source, ABB-supplied or otherwise, at their fingertips.
These new communication modules can be used to expand existing Symphony Plus HR Series (Harmony Rack) systems or earlier generation Symphony
Harmony or INFI 90 rack systems, just as other SD modules.
The other challenge of moving beyond the boundaries of traditional DCS is that data is no longer moving within a local area network, isolated from the rest of the world. Instead, business critical data is now travelling out in the world, and since these are often critical infrastructures, data security is vitally important in distributed systems.
ABB has invested a huge effort to build essential cyber-security features into the Symphony Plus architecture so it can robustly defend against cyber security attacks, in an environment which is by nature more exposed and susceptible to security intrusions.
Remote operation and maintenance
Very often, renewable generation owners are small and independent operators without the financial resources of traditional power generation conglomerates. To serve this market, ABB can provide remote monitoring, maintenance, data analysis and performance reviews of all customer systems from remote ABB operations centers. The service is managed directly by ABB, which can connect remotely to all customer installations.
This is basically a cloud service offered under a “Software as a Service” (SaaS) contract, where ABB’s remote control room substitutes itself for the customer's operation center. The customer decides what level of service they need, ranging from basic supervision and some monitoring of the amount of power produced, etc. ABB offers customers a library of specific KPIs, which are set up to collect and analyze large amounts of data and from this, develop data indicators that tell operators exactly how their systems are performing.
The automation journey continues
In the future, it is reasonable to expect some consolidation in the renewable segment, as smaller operators join forces to create larger entities, which might require larger control centers that can provide precise overviews of more and more complex operations.
Large or small, traditional generation or renewable, customers want to get as much life and power from their plants as possible. They want automation systems that will operate for several decades, be supported by spare parts and tune-ups over that time, and which will not simply
be erased and the investment lost when the time comes for change.
ABB’s challenge as an automation supplier is to continue evolving Symphony Plus in a way that will provide useful new features to the installed base, without asking customers to radically change the technology they already have and know.
Traditional thermal power generation is not predicted to grow much in more developed countries, but renewable generation will, while thermal systems are continuing to expand in developing countries, some of which are also rapidly developing renewable generation capacity. Symphony Plus must be ready to serve a divergent power generation market and its different segments.
The push coming from renewables will likely continue to drive ongoing changes in control system architecture. ABB’s task is to provide technology capable of accommodating the changes at work in the power generation sector with directly relevant features, like cloud technology, enhanced security, remote control, data analysis, in systems that are as simple and easy to operate as a smart phone app.