Hierarchical Control and Industrial Automation

Prof. Arpit Jainarpit.eic@gmail.com+91-8650304041

Automation

• Automation is the use of control systems such as computers to control industrial machinery and processes, reducing the need for human intervention.

Expectations from automations

High reliability and availability.Fast troubleshooting.Easily configurable.Process optimization.Asset optimization .Flexibility.Able to take each & every decision with minimum assistance from human intervention.

Applications of Automation

Power generation Manufacturing Building Transportation Mining Oil & gas industries Pharmaceutical And many more…..

The famous Pyramid of Automation

This pyramid is considered as reference in industries while developing automation solutions.

Manufacturing Execution

Supervision (SCADA)

Group Control

Individual Control

Field

Primary technology

Enterprise

Detailed structure of control system hierarchy

A standard functional hierarchy by ANSI/ISA-95

Building blocks of Automation

Sensors and actuatorsAnalog and digital I/O modulesDDC direct digital controlPLC being replaced by PACsDCS distributed control systemsSCADA supervisory control and data acquisitionMES manufacturing execution systemERP enterprise resource planning

Sensors and Actuators

• Intelligent sensors• Biosensors• Optical fiber sensors• Expert sensors• Digital actuators

Biosensor

Motor with built in DAC

Analog and digital I/O module

Analog I/O moduleDigital I/O moduleMixed I/O moduleGenius I/O module

Direct Digital control

Mainly used for control of critical process parameters

PLC Programmable Logic Controllers

• A programmable logic controller (PLC) or programmable controller is a digital computer used for automation purposes. PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact

A typical rack mounted PLC

PAC Programmable Automation Controllers

• PAC has all the capabilities of PLC with some added features like task flexibility, integrated communication interfaces and very high computing power.

Architecture of PAC

Architecture details of SEL-2411 PAC

Benefits of PAC over PLC

PAC support many standard communication protocols PAC can do many tasks simultaneously

DCS Distributed Control System

Architecture of DCS Control room of a DCS system

DCS system on a plant floor

SCADA Supervisory control and data acquisition system

In early 1970s all instruments were directly wired to the control room

SCADA Supervisory control and data acquisition system

SCADA architecture

Main functions of SCADA

- displays the current state of the process (visualization)- display the alarms and events (alarm log, logbook)- display the trends (historians) and analyse them- display handbooks, data sheets, inventory, expert system (documentation)- allows communication and data synchronization with other centres

Knowledge management for design and manufacturing

MES Manufacturing Execution SystemManufacturing Execution Systems (MES) manage and monitor work-in-process on the factory floor including manual or automatic labor and production reporting, as well as on-line inquiries and links to tasks that take place on the production floor. Manufacturing Execution Systems may include one or more links to work orders, receipt of goods, shipping, quality control, maintenance, scheduling or other related tasks. Here we are dealing with the Level 3 of ANSI/ISA-95 standard which is shown in figure

Reasons to implement MES

• Automate management of recipes (process manufacturers)• Scheduling, including the management of priorities• Production reporting• Key Performance Indicator (KPI) tracking• Event or exception management• Product or materials tracking• Intelligent decisions to influence production and cost

management• Measure and manage operational equipment efficiency, or

OEE• Ease management of resources, including inventory and

personnel

Standardized MES architecture by ISA-95

S95.01There are eleven generic functions found in an MES suite, which are defined by the S95.01 standard provided by the Instrumentation, Systems and Automation (ISA). These functions are not the be all and end all of MES functionality but are meant to provide a solid category of capabilities. The eleven functions are:

Operations/Detailed Scheduling Resource Allocation & Status Dispatching Production Units Document Control Product Tracking & Genealogy Performance Analysis Labor Management Maintenance Management Process Management Quality Management Data Collection Acquisition.

Link between SCADA and MES systems

Plant intelligence links between SCADA and MES

Benefits of implementing MES

ERP Enterprise Resource Planning• ERP is an enterprise-wide information system designed to coordinate all the

resources, information, and activities needed to complete business processes such as order fulfillment or billing.

Interactions between ERP and plant floor

• Current ERP vendors (SAP) provide over 30 different interactions between plant floor and ERP, some of them are shown below

Response time and hierarchical level

PlanningLevel

ExecutionLevel

ControlLevel

SupervisoryLevel

ms seconds hours days weeks month years

ERP(Enterprise Resource

Planning)

DCS

MES(Manufacturing

Execution System)

PLC(Programmable Logic Controller)

(Distributed Control System)

(Supervisory Control and Data Acquisition)

SCADA

Complexity and Hierarchical levels

Conclusion

• Industrial Automation is a discipline that includes knowledge and expertise from various branches of engineering Industrial Automation Engineers have always drawn new technologies and implemented original or enhanced versions to meet their requirements. As the range of technology diversifies the demand on the innovative ability of these Engineers has increased. Hence in order to survive in today’s competitive manufacturing markets, manufacturing systems need to adapt at an ever-increasing pace to incorporate new technology which can lower the cost of production, while maintaining quality and delivery schedules.