Industrial process environments are growing more complex with each passing year, while at the same time industry faces a technical skills shortfall. In light of these realities, process automation systems have, arguably, never been more important, and the selection and implementation of distributed control systems (DCS) is central to the modern industrial automation challenge. An effective DCS strategy can help an organization streamline its processes to make the most of limited resources, while a poorly thought out DCS can waist valuable time and money and, perhaps, ultimately lead to the demise of the business as a whole.
Coping with Complexity
|Faster processors enable lower-cost connections and integration of more powerful applications. The new control processor used in the Foxboro control systems runs at 500 MHz and can process 16,000 blocks per second. (Image courtesy of Schneider Electric)|
Today’s industrial companies are looking for DCSs that provide a common approach across their systems to simplify design, implementation, and operation. To help process-driven businesses address these issues, automation systems have become increasingly capable of adapting to process changes quickly and easily.
The evolution of DCS technology has been driven by the increasing speed and complexity of business, and the need to respond to market changes in real-time. Modern control systems offer faster processors than previous generations of technology, enabling integration of workflow engines at the platform layer of the automation software architecture. This allows engineering, operation, and maintenance procedures to be embedded into the system environment for on-demand access.
“These workflows can offer operational insight to new personnel from more experienced personnel who may not even be in the organization any more,” says Alain Ginguene, director of Foxboro Evo DCS for Schneider Electric, which recently acquired Invensys. “Highly complex and error-prone operations, such as plant and unit start-up and shutdown, can be guided through the use of the workflow engine. Also, operators and maintenance workers can be guided through unexpected and perhaps unsafe events through the intellectual property embedded in automatically triggered workflows.”
While the technology is getting more sophisticated to help end-users more effectively address their process automation challenges, process complexity presents an increasingly troublesome challenge for engineers. “Remedying production problems based on root cause analysis is a key role that systems engineers play in increasing production value and managing constraints,” says Ginguene. “They must do this in the context of many different systems, each of which may be from a different vendor and each of whose technologies may be changing rapidly.”
One area of complexity is flow measurement, which demands increasing precision since these functions are often associated with custody-transfer applications. In recent years, prevailing standard digital fieldbus protocols have helped drastically reduce the field wiring needed to extract multiple measurements from the same device. This enables readings of potential, mass flow, velocity, and total flow from a common device. The precision required for these readings often exceeds that which is provided by traditional input cards.
The Field Device Technology (FDT) standards advanced by the FDT Group address this by standardizing the communication and configuration interface between all field devices and host systems. Ginguene says some field device managers can apply these standards to simplify device maintenance, helping technicians extract the “as promised” value from the technology they use. He says this also ensures that the flowrate seen at the device level is exactly the same as what is seen on a display screen.
Helping engineers quickly understand the many disparate systems they may interface with on a daily basis is a fundamental role of the modern DCS and automation system as a whole. This understanding is key to the effective diagnosis of production problems.
According to Ginguene, engineers no longer have the time to analyze detailed sequential flow charts, ladder logic, function block diagrams, or structured text to troubleshoot problems. He says engineers need more intuitive, easier-to-use interfaces.
The Scientific Apparatus Manufacturers Association’s (SAMA’s) Process Visualization Standard addresses ease-of-use. The SAMA standard has been used in the power industry for more than 20 years, and it is now gaining traction in other industries as well. The tools offered through the standard present a much higher-fidelity representation of the relevant PID blocks and the flow of data through them, including dynamic filters that help engineers focus more directly on the control mode in which they are working. According to Ginguene, users report that the intuitive modeling of SAMA tools can reduce engineering workloads by as much as 60 percent.
Given the complexity and inherently integrated nature of industrial process automation in the modern age, many companies are partnering with experts in the field to ensure the proper buildout of their system. “There’s a trend towards Main Automation Contractor (MAC) projects where the DCS supplier provides a complete automation solution for end-users, including DCS, process safety systems, and instrumentation,” says Lenard Huang, analyst for IHS Technology. He says this strategy helps end-users ensure their automation system is designed from the ground up for interoperability and helps mitigate many of the issues end-users currently face regarding the integration of disparate systems.
|Over the past ten years, HMIs have evolved to provide operators better context to adjust set points or otherwise respond to abnormal situations with maximum speed and effectiveness. (Image courtesy of Schneider Electric)|
Cloud Computing & Cybersecurity
Cloud computing and cybersecurity are two relatively new trends that will play an increasingly important role in DCS and process automation going forward. Cloud computing—where hardware, software, and data are delivered via the Internet (or an Intranet)—impacts DCS technology from delivery and disaster recovery perspectives.
At delivery, decoupling the configuration layer from the run-time layers enables significant portions of the system to be configured and tested in the cloud. This speeds project delivery by enabling engineering in the context of a hypothetical future state.
For disaster recovery, mirroring the operation of control logic in remote back-up locations, such as virtual servers, eliminates dependencies between the physical hardware and software, and provides users with more capability to manage the availability of their applications, servers, and equipment. Because the CPU, operating system, and communications are relatively contained, it is much easier to move virtual machines between host computers. This enables the implementation of a variety of failsafe scenarios, each of which provide options for different levels of redundancy, making systems more resilient, less prone to equipment failure and site failure, and simpler to upgrade.
Cybersecurity protection is an area of increasing concern among industrial organizations “Information technology leaders, such as Microsoft, Symantec, and a number of standards and regulatory agencies have been cooperating and providing guidance that defines the essential requirements for cyber hardening,” says Ginguene. “A cybersecure system should be built on technology that has been continuously hardened according to these guidelines for a lengthy period of time.
Ideally, Ginguene says a new automation system should have Achilles Certification from Wurldtech, which provides a benchmark for deployment of secure industrial control devices. However, Ginguene says technology hardening is only part of the solution. He recommends company policies be established for monitoring on a continuous basis. Invensys (now Schneider Electric) guides companies in implementing cybersecurity best practices in four areas:
- Security assessment
- Security architecture and policy
- Security modernization
- Security management
Huang says cybersecurity has been a significant driver of revenue for DCS suppliers, who have been providing retrofit cybersecurity solutions to end-users and integrating cybersecurity functionality into their systems, particularly in mature markets. “Cybersecurity should be a real concern for end-users,” says Huang. “Most of the large, IT-driven companies proactively approach this subject; however, smaller, less IT-driven companies may be behind in this space.”
Ginguene says the future will likely bring larger and more complex plants, making it harder for operators to understand plant operations deeply enough to handle the increased load. He says the operators of the future will have more instrumentation to manage, more data to process, and more possible upsets to address.
“Unlike their predecessors, who could view a panel board to almost instantly receive a picture of what was going on in the plant, today’s operators now rely on workstation screens,” says Ginguene. “They can get more information and usually get it faster—but there are more steps in figuring out where to look.”
In response to this trend, Ginguene says automation systems are increasingly evolving to provide operations, engineering, maintenance, safety, and management added insight on the context of their actions. Ginguene says end-users can expect the next generation of DCSs to increasingly integrate applications that enable greater adaptability to changing business conditions including:
- Simulation, modeling, and software for operator training, optimization and multivariable process control;
- Enterprise manufacturing intelligence for real-time insight into trends in production and operation;
- Corporate energy management for fluctuating energy costs/supply;
- SCADA applications that are customized by application;
- Enterprise asset management software with improved diagnostics, inventory management, and preventive and predictive maintenance; and
- Mobile applications, which deliver real-time field access and reporting.
Huang says he expects suppliers to continue to develop integrated/standardized hardware/software platforms to enable more streamlined system upgrades. He says cybersecurity will also become a key end-user requirement, not only in mature markets, but also in emerging ones. And he expects to see an increased focus on user-centric technologies to enhance operator effectiveness. He says, “Systems will be more robust and easier to install and maintain, enabling longer lifecycles and reduced overall cost.”
Matt Migliore is the director of content for Flow Control magazine and FlowControlNetwork.com. He can be reached at Matt@GrandViewMedia.com.