Create a free Manufacturing.net account to continue

Finding The Middle Ground In Manufacturing Through Hybrid Control Systems

The Life Sciences industry represents an ideal environment for deploying Hybrid Control Systems. After all, the industry itself is a hybrid. Life Sciences (pharmaceutical and biopharmaceutical, in particular) is one of those few industries that has process, batch and discrete manufacturing all as critical phases in the production process.

The Life Sciences industry represents an ideal environment for deploying Hybrid Control Systems. After all, the industry itself is a hybrid. Life Sciences (pharmaceutical and biopharmaceutical, in particular) is one of those few industries that has process, batch and discrete manufacturing all as critical phases in the production process.

Automotive manufacturing is all discrete manufacturing; refining is nearly all continuous manufacturing. Life Sciences manufacturing, however, contains three distinct and critical manufacturing phases. Primary or bulk pharmaceutical manufacturing involves the production of bulk powder or liquids and represents true chemical process manufacturing.

Control systems for primary manufacturing are typically Distributed Control System (DCS) based, and often used in conjunction with a Plant Historian. Secondary pharma manufacturing facilities contain batch-oriented unit operations like drying, blending and granulation suites. Secondary facilities contain some DCS control and also use Programmable Logic Controller (PLC), Supervisory Control and Data Acquisition (SCADA) and Batch Execution systems control. Finally, the packaging operation is completely discrete-oriented and is typically controlled solely by PLCs and SCADA software. Hybrid Control Systems offer the best of all control worlds and are rapidly gaining momentum as an alternative to traditional DCS, PLC and Batch control systems for pharmaceutical and biopharmaceutical manufacturing.

Distributed Control Systems (DCSs) have a storied history in the process world and still enjoy a very large installed base today. DCSs are dedicated, distributed systems with proprietary communication protocols that are used for control of a variety of manufacturing operations. DCSs were invented to replace analog hardware controllers via function blocks to control process-oriented manufacturing operations like refining, chemical, petrochemical and bulk pharmaceutical manufacturing. DCS solutions proved to be extremely reliable, but were primarily hardware-based solutions based on proprietary technology. This made them effective tools but extremely expensive to maintain, and very inflexible, especially after the Windows revolution.

PLCs, on the other hand, evolved from a completely different industry: automotive, and were invented to replace costly relays and timers. PLC control was, and still is, centered largely on event-based control (versus time or scan-based for DCS), such as responding to an input from a limit switch or position sensor. PLCs excel at performing a specific set of functions, like assembly or packaging, at a very high speed and very predictably. When used in conjunction with SCADA software, this PLC/SCADA combination provides the operator a highly graphical interface to the controller and the solution is very well suited for primarily discrete and some process oriented applications.

Finally, Batch Control Systems offer a third alternative for control. Batch control solutions can be part of a larger DCS solution or made up a software and PLC based approach. Batch Control applications are designed to control the sequence of batch execution, provide operator work instructions, and manage recipes and equipment.

What is Hybrid Control?
A Hybrid Control System is comprised of hardware and software that provides integrated process control for continuous and hybrid process applications. Hybrid Control provides batch and continuous process control strategies and utilities typically associated with DCS systems at a traditional HMI/PLC solution openness, flexibility, and price structure.

The traditional value proposition for Hybrid Control is a modular system extending from process instruments through controllers and applications to maintenance and business financial systems. Hybrid Control truly provides information connectivity from shop floor to top floor. Integrated tools provide a single point of configuration via a global namespace preventing replication of tags. This type of solution provides a combined information and automation architecture as well as integrated Historian and Batch solutions.

The more progressive Hybrid Control Systems on the market today offer more tightly integrated, powerful controller platforms, operator workstations and consoles and a scalable process historian. This type of architecture provides for a highly flexible solution that leverages standards such as S88, S95 and S99, and is based on open technologies such as OPC, Ethernet, Pentium-class CPUs, and a large library of drivers and function blocks. This makes integration to third party systems and applications quick and simple.

Hybrid Control Systems offer a unique opportunity for the Life Sciences industry today. As drug manufacturers struggle to improve their manufacturing operations they are investigating new ways to manufacture product. The introduction of the PAT initiative as well as cGMPs for the 21st Century have opened the door for innovation in the production environment. More and more Life Sciences companies are looking at new ways to improve yields, reduce manufacturing costs and total cost of ownership and integrate islands of automation. Hybrid control systems have been on the market for nearly 10 years and have slowly been gaining momentum as an alternative to traditional DCS and PLC based control systems.

Why Hybrid Control?
Hybrid Control offers integrated architectures, advanced PC-based programming software, and industrial hardware. For Life Sciences customers, Hybrid Control allows for leveraging the existing installed base of products including SCADA, Plant Historian and Batch Execution software. Process Analytical Technology initiatives also open the door for an integrated Hybrid Control and PAT solution. The key value offering of a Hybrid Control System is a viable alternative to traditional DCS solutions and with that, a lower TCO. In addition, Hybrid Control Systems provide a much better process control system than could be accomplished with the traditional PLC and HMI approach.

Target areas of application for Hybrid Control in the Life Sciences industry are solution preparation in traditional pharmaceutical companies as well as the entire production environment for biopharmaceutical manufacturing (bioreactors or fermentation, purification) and the “fill” process of a fill/finish facility. Secondary pharmaceutical manufacturing plants have a combination of batch and discrete processes and Hybrid Control provides a strong value proposition in these types of environments because it can handle both types of processing in a single platform.

Beyond the architecture and control benefits, Hybrid Control offers abundant benefits for management as well. The information-enabled platforms of today offer Key Performance Indicators (KPIs) and multiple plant real time business intelligence. One of the key challenges for managers today is visibility into their production operations. Hybrid Control Systems aggregate islands of automation into a coherent and unified information exchange allowing better visibility to minimize risk and maximize yields. Hybrid Control Systems with integrated Batch solutions provide outstanding control to achieve batch-to-batch consistency, ensuring tight variance of all ingredient deliveries including weigh and dispense. Flexible systems built on standards allow for fast changeovers with s88 based batch capabilities, compliance enabling technology with 21CFRpart11 features, and higher plant efficiency and capacity and resource utilization.
With all of this advanced flexibility and capability, Hybrid Control Systems stand well positioned for a bright future in the rapidly changing Life Sciences manufacturing environment.

More in Operations