ABB1409-Grid
ABB1409-Grid
ABB1409-Grid
ABB1409-Grid
ABB1409-Grid

Embrace Your Inner Grid

Oct. 14, 2014
Advancing Communication Standards, Converging Platforms Make It Easier Than Ever to Unify Process Automation and Electrical Systems

It's always been difficult to argue against the motherhood and apple pie of integrated systems. A vision of on-demand data flowing freely among formerly isolated information silos is easy. Building and maintaining the custom interfaces often needed to realize the vision is hard.

But one by one, the architectural barriers to painless information integration are coming down. In this special report, we'll focus in particular on the convergence of communication protocols and underlying technologies in the arenas of process automation and electrical controls, and how this convergence is allowing a growing number of industrial companies to reduce capital costs and operating expenses even as they improve overall plant reliability and energy efficiency.

Two worlds, two systems

Electrical energy is a vital input to process manufacturing operations, often secondary only to raw materials. And, just as the flow of process fluids through pipes, valves and vessels typically is controlled by a dedicated process automation system, the flow of electrons through transformers, circuit breakers and motors is the domain of a dedicated electrical control system.

In a traditional plant, both types of systems work largely independently to ensure safe, uninterrupted production. Indeed, the differing dynamics of electrical and process phenomena has led over the years to the development of parallel systems, suppliers and support organizations for each type of system.

ABB's integrated approach to in-plant substation automation and process electrification incorporates both process control level protocols such as PROFIBUS, PROFINET and MODBUS as well as MMS and GOOSE messaging specific to IEC 61850.

Typically, the process draws what power it needs according to operational setpoints from the process automation system, and the electrical control system strives to meet those requirements in a safe, stable fashion. If there's any coordination at all between the two systems beyond manual intervention, hardwired I/O or custom interfaces are used to swap a few key variables or interlocks. Significant effort and considerable expense are required to establish and maintain even this limited connectivity in good working order.

Grid standards with in-plant implications

Even as process industry management demands for improved visibility into real-time energy usage escalated over recent years in response to increasingly volatile energy prices, the electrical power transmission and distribution industry was developing a way for substation automation systems and other intelligent electronic devices (IED) to communicate and interoperate, regardless of manufacturer. The end result, first approved in 2004, is standard 61850 of the International Electrotechnical

Commission (IEC). See sidebar below for more details.

And while transmission and distribution systems were the primary target users of IEC 61850, the standard also has allowed system providers to bring added functionality to their integrated process and power offerings. ABB, for example, a global leader in both process automation and electrical systems, integrated IEC 61850 into its System 800xA to provide a single, unified control and optimization platform for all of a plant's process automation and electrification needs.

Integration as matter of course

System controllers from ABB can now function as controllers in both domains, simultaneously speaking (and translating where appropriate) the languages of both process automation and electrification. This means that operational data from in-plant electrical equipment—ranging from high-voltage substations to low-voltage drives and motors—can transparently feed real-time process control and optimization algorithms as well as other plant information systems. For example, motor data and diagnostic information that once was stranded in the process automation system is now readily accessed by the electrical maintenance technicians charged with their upkeep.

An Orientation to the Power Industry's IEC 61850 Standard

First issued in 2004, standard 61850 of the International Electrotechnical Commission (IEC 61850) was created by the electric power industry to facilitate the communication and interoperability of the intelligent electronic devices (IEDs) that increasingly characterize today's power distribution grid.

At the heart of the standard are object-oriented data models designed to facilitate semantic commonality of essential electrical infrastructure functions among disparate systems and devices. The current edition of 61850 also defines an Ethernet-based, high-speed means of communicating generic object-oriented substation events (GOOSE) horizontally among IEDs for interlocks and protection schemes as well as TCP/IP-based MMS for vertical integration into supervisory systems.

And while transmission and distribution systems were the primary target users of IEC 61850, the standard also has important implications for both power generation facilities and other process manufacturing sites. For starters, it's done much to increase the visibility of operating data and diagnostic information from plant electrical assets. Indeed, the operations of many older in-plant substations are still maintained by blind controllers unable to communicate back to operations. Periodic field observations of transformer temperatures and power meter readings attempt to fill this information gap, but the practice is relatively unsafe, unproductive and untimely as well. Electrical integration via IEC 61850, in contrast, provides seamless, control room access to real-time operational data and diagnostics for all integrated system users.

Regardless of their integration with a plant's process automation infrastructure, IEC 61850 represents significant cost savings relative to the extensive hardwiring for IED communication it replaces. Ethernet connectivity means no I/O—and no hardwiring—is required for communication among IEDs. Fewer wires mean fewer terminations, lower installation costs, and improved organization within substation cubicles. Further, fiber optic networks mean that communication links can run closer to busbars without risk of electromagnetic interference.

In effect, the company's process automation and electrical control systems are now one and the same. Electrical integration isn't an add-on, it's part and parcel of the System 800xA architecture. And not only is this integration delivered cost effectively, the integrated system actually costs less to acquire, engineer and maintain than two dedicated systems.

Leandro Monaco, ABB global product manager for electrical integration, estimates up to 30% investment cost savings relative to a non-integrated, two-control system approach. And at the Presidente Getúlio Vargas (Repar) refinery of Petrobras in Brazil, engineers credit the refinery's integrated process and power systems from ABB with a 30% savings in engineering costs, 15% savings in installation time, and 20% savings in training costs.

It's all about control

The improved ability to control capital costs and operational expenses is but one facet of the overall performance improvements made possible by a holistic view of plant data and asset information. A unified platform means users gain better control of overall plant productivity, availability and safety as well. Further, as individual drives, motors, breakers and relays reveal the formerly stranded details of their energy usage in real-time, opportunities to control and conserve energy come to the fore.

ABB's Leandro Monaco relates how at one mining company where energy has come to dominate its variable costs, the "new" key performance indicator (KPI) enabled by integrated process and electrical systems is tons/kWh, replacing the traditional production metric of tons/year. This ability to draw a straight line between production output and energy consumption means that the company can now vary production rate at its various mines based on profitability measured directly in the process automation system. "How powerful is that?" Monaco asks.

In each of the three articles that form the balance of this special report, we'll explore in greater detail the operational advantages of ABB's integrated approach to process automation and electrical controls. We'll explain why embracing your plant's inner grid makes sense from the perspectives of operational and capital expense savings, improved plant performance, and real-time energy management, too.