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Impacts of Automation on Precision References 125

Recent trends and competitive pressures indicate

that more knowledge has been generated about pro-

cesses, which leads to the reduction of apparent

nonsystematic variations. With increased knowledge

and technical capabilities, producers are developing

more complex, high-value products with smaller num-

bers of components and subassemblies. This trend leads

to even more automation with less cost.

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126 Part A Development and Impacts of Automation

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Part A 7

127

Trends in Aut

8. Trends in Automation

Peter Terwiesch, Christopher Ganz

The present chapter addresses automation as

a major means for gaining and sustaining produc-

tivity advantages. Typical market environment fac-

tors for plant and mill operators are identiﬁed, and

the analysis of current technology trends allows us

to derive drivers for the automation industry.

A section on current trends takes a closer look

at various aspects of integration and optimiza-

tion. Integrating process and automation, safety

equipment, but also information and engineer-

ing processes is analyzed for its beneﬁt for owners

during the lifecycle of an installation. Optimiz-

ing the operation through advanced control and

plant asset monitoring to improve the plant per-

formance is then presented as another trend that

is currently being observed. The section covers

system integration technologies such as IEC61850,

wireless communication, ﬁeldbuses, or plant data

management. Apart from runtime system inter-

operability, the section also covers challenges in

engineering integrated systems.

The section on the outlook into future trends

addresses the issue of managing increased com-

plexity in automation systems, takes a closer look

at future control schemes, and takes an overall

view on automation lifecycle planning.

Any work on prediction of the future is based on

an extrapolation of current trends, and estimations

of their future development. In this chapter we

will therefore have a look at the trends that

drive the automation industry and identify those

developments that are in line with these drivers.

Like in all other areas of the industry, the future

of automation is driven by market requirements on

one hand and technology capabilities on the other

hand. Both have undergone signiﬁcant changes in

recent years, and continue to do so.

In the business environment, globalization

has led to increased worldwide competition. It

is not only Western companies that use offshore

production to lower their cost; it is more and

8.1 Environment ........................................ 128

8.1.1 Market Requirements ................... 128

8.1.2 Technology .................................. 129

8.1.3 Economical Trends ....................... 129

8.2 Current Trends ..................................... 130

8.2.1 Integration.................................. 130

8.2.2 Optimization ............................... 138

8.3 Outlook ............................................... 140

8.3.1 Complexity Increase...................... 140

8.3.2 Controller Scope Extension ............ 141

8.3.3 Automation Lifecycle Planning....... 141

8.4 Summary ............................................. 142

References .................................................. 142

more also companies from upcoming regions such

as China and India that go global and increase

competition. The constant strive for increased

productivity is inherent to all successful players in

the market.

In this environment, automation technology

beneﬁts from the rapid developments in the in-

formation technology (IT) industry. Whereas some

15 years ago automation technology was mostly

proprietary, today it builds on technology that

is being applied in other ﬁelds. Boundaries that

have clearly been deﬁned due to the incompat-

ibility of technologies are now fully transparent

and allow the integration of various requirements

throughout the value chain. Field-level data is

distributed throughout the various networks that

control a plant, both physically and economically,

and can be used for analysis and optimization.

To achieve the desired return, companies need

to exploit all possibilities to further improve their

production or services. This affects all automation

levels from ﬁeld to enterprise optimization, all

lifecycle stages from plant erection to dismantling,

and all value chain steps from procurement to

service.

In all steps, on all levels, automation may play

a prominent role to optimize processes.

Part A 8

128 Part A Development and Impacts of Automation

8.1 Environment

8.1.1 Market Requirements

Today, even more than in the past, all players in the

economy are constantly improving their competitive-

ness. Inventing and designing differentiating offerings

is one key element to achieve this. Once conceived,

these offerings need to be brought to market in the most

efﬁcient way.

To deﬁne the efﬁciency of a plant or service,

we therefore deﬁne a measure to rate the various

approaches to optimization: The overall equipment

effectiveness (OEE). It deﬁnes how efﬁciently the

equipment employed is performing its purpose.

Operational Excellence

Looking at the graph in Fig.8.1, we can clearly see

what factors inﬂuence a plant owner’s return based

on the operation of his plant (the graph does not

include factors such as market conditions, product

differentiation, etc.). The inﬂuencing factors are on

the cost side, mainly the maintenance cost. Together

with plant operation, maintenance quality then deter-

mines plant availability, performance, and production

quality. From an automation perspective, other fac-

tors such as system architecture (redundancy) and

system ﬂexibility also have an inﬂuence on availabil-

ity and performance. Operation costs, such as cost

of energy/fuel, then have an inﬂuence on the product

cost.

Planned hours

Max. prod/h

8400

500

Theoretical

prod./year Actual prod./year Revenues

4200 000 3189690 95691

Availability

Performance

Quality

83.00%

91.50%

100.00%

OEE

Contrib.

margin/year Profit Profiability

75.95% 25518 10 968 11.46%

Price/unit

Variable cost/unit

0.03

0.022

Contribution

margin/unit

0.008

Direct. maint. cost

Depreciation

Other fixed cost

4050

5000

5500

Fixed cost/year

14 550

Fixed assets

Net working cap.

150000

18400

Capital employed

Return on

net assets

168400 6.51%

Fig. 8.1 Overall equipment effectiveness

Future automation system developments must in-

ﬂuence these factors positively in order to ﬁnd wide

acceptance in the market.

New Plant Construction

Optimizing plant operations by advanced automation

applications is deﬁnitely an area where an owner gets

most of his operational beneﬁts. An example of the

level of automation on plant operations can be seen in

Figs. 8.2 and 8.3. When it comes to issues high on the

priority list of automation suppliers, delivery costs are

as high if not even higher. Although the main beneﬁt of

an advanced automation system is with the plant owner

(or operator), the automation system is very often not

directly sold to that organization, but to an engineer-

ing, procurement, and contsruction (EPC) contractor

instead. And for these customers, price is one of the top

decision criteria.

As automation systems are hardly ever sold off the

shelf, but are designed for a speciﬁc plant, engineering

costs are a major portion of the price of an automation

system.

An owner who buys a new automation system looks

seriously at the engineering capabilities of the supplier.

The effect of efﬁcient engineering on lowering the offer

price is one key item that is taken into account. In to-

day’s fast developments in the industry, very often the

ability to deliver in time is as important as bottom-line

price. An owner is in many cases willing to pay a pre-

Part A 8.1

Trends in Automation 8.1 Environment 129

Fig. 8.2 Control of plant operations in the past

mium for a short delivery time, but also for a reduced

risk in project execution. Providing expertise from pre-

vious projects in an industry is required to keep the

execution risk manageable. It also allows the automa-

tion company to continuously improve the application

design, reuse previous solutions, and therefore increase

the quality and reduce the cost of the offering. When

talking about the future of automation, engineering will

therefore be a major issue to cover.

Plant Upgrades and Extensions

Apart from newly installed greenﬁeld projects, plant

upgrades and extensions are becoming increasingly im-

portant in the automation business. Depending on the

extent of the extension, the business case is similar to

the greenﬁeld approach, where an EPC is taking care of

all the installations. In many cases however, the owner

takes the responsibility of coordinating a plant upgrade.

In this case, the focus is mostly on total cost of owner-

ship.

Fig. 8.3 Trend towards fully automated control of plant

operations

Furthermore, questions such as compatibility with

already installed automation components, upgradestrat-

egies, and integration of old and new components

become important to obtain the optimal automation so-

lution for the extended plant.

8.1.2 Technology

Increasingly, automation platforms are driven by infor-

mation technology. While automation platforms in the

past were fully proprietary systems,today theyuse com-

mon ITtechnology inmost areas of the system [8.1]. On

the one hand, this development greatly reduces develop-

ment costs for such systems and eases procurement of

off-the-shelf components. On the other hand, the lifecy-

cle of a plant (and its major component the automation

system), and IT technology greatly differs. Whereas

plants follow investment cycles of 20–30 years, IT

technology today at ﬁrst sight has reached a product

lifecycle of less than 1 year, although some underly-

ing technologies may be as old as 10years or more

(e.g., component object model (COM) technology, an

interface standard introduced by Microsoft in 1993).

Due to spare parts availability and the lifecycle of

software, it is clear that an automation life span of

20years is not achievable without intermediate updates

of the system. A future automation system therefore

needs to bridge this wide span of lifecycle expectations

and provide means to follow technology in a manner

that is safe and efﬁcient for the plant.

Large investments such as ﬁeld instrumentation, ca-

bling and wiring, engineered control applications, and

operational data need to be preserved throughout the

lifecycle of the system. Maintaining an automation sys-

tem as one of the critical assets of a plant needs to be

taken into considerationwhen addressingplant lifecycle

issues. In these considerations, striking the right balance

between the beneﬁts of standardized products, bringing

quality, usability,cost, andtraining advantages, and cus-

tomized solutions as the best solution for a given task

may become critical.

8.1.3 Economical Trends

In today’s economy, globalizationis named as the driver

for almost everything. However, there are some aspects

apart from global price competitiveness that do have an

inﬂuence on the future of automation.

Communication technology has enabled compa-

nies to spread more freely over the globe. While

in the past a local company had to be more or

Part A 8.1

130 Part A Development and Impacts of Automation

less self-supporting (i.e., provide most functions lo-

cally), functions can today be distributed worldwide.

Front- and back-ofﬁce organizations no longer need

to be under the same roof; development and produc-

tion can be continents apart. Even within the same

project, global organizations can contribute from vari-

ous locations.

These organizations are interlinked by high-

bandwidth communication. These communication links

not only connect departments within a company, they

also connect companies throughout the value chain.

While in earlier days data between suppliers and

customers were exchanged on paper in mail (with cor-

responding time lags), today’s interactions between

suppliers and customers are almost instant.

In today’s business environment, distances as well

as time are shorter, resulting in an increase in business

interactions.

8.2 Current Trends

8.2.1 Integration

Looking at the trends and requirements listed in the

previous Sections, there is one theme which supports

these developments, and which is a major driver of the

automation industry: integration. This term appears in

various aspects of the discussions around requirements,

in terms of horizontal, vertical, and temporal integra-

tion, among others. In this Section we will look at

various trends in integration and analyze their effect on

business.

Process Integration

Past approaches to ﬁrst developthe process and then de-

sign the appropriate control strategy for it do not exploit

the full advantages of today’s advanced control capabil-

ities. If we look at this under the overall umbrella of

integration, there is a trend towards integrated design of

process and control.

In many cases, more advanced automation solutions

are required as constraints become tighter. Figures 8.4–

8.6 show examples which highlight the greater degree

and complexity of models (i. e., growing number of

constraints, reduction in process buffers, and nonlinear

dynamic models). There is an ongoing trend towards

tighter hard constraints, imposed from regulating au-

Fig. 8.4 Trend towards reduction of process buffers (e.g., supply chain, company, site, unit)

thorities. Health, safety, and especially environmental

constraints are continuously becoming tighter.

Controllers today not only need to stabilizeone con-

trol variable, or keep it within a range of the set-point.

They also need to make sure that a control action does

not violate environmental constraints by producing too

much of a by-product (e.g., NO

). Since many of these

boundary conditions are penalized today, these control

actions may easily result in signiﬁcant ﬁnancial losses

or other severe consequences.

In addition to these hard constraints, more and more

users want to optimize soft constraints, such as energy

consumption (Fig. 8.7), or plant lifecycle. If one ramps

up production in the fastest way possible (and maybe

meet some market window or production deadline), en-

ergy consumed or plant lifecycle consumption due to

increased stress on components may compensate these

quick gains. An overall optimization problem that takes

these soft constraints into account can therefore result

in returns that are not obvious even to the experienced

operator.

A controller that can keep a process in tighter

constraints furthermore allows an owner to optimize

process equipment. If the control algorithm can guaran-

tee a tight operational band, process design can reduce

buffers and spare capacity. Running the process closer

Part A 8.2

Trends in Automation 8.2 Current Trends 131

Fig. 8.5 Trend towards broader scope, more complex, and integrated online control, for example, in pulp operations

Dynamic

mass balance

k+1

= g(x

)+v

Inlet pulp

Inlet steam

Inlet WL

Outlet condensate

Outlet BL

Outlet NCG

Outlet pulpOutlet water

Connection of units, pipes

and measurements

Server

Measurement

542|441

BK1

k+1

= f (x

, u

)+w

Parameters

542|441

First-order mass balance

542|441

NCG til l

Starkgasdestruktion

Tunnlut till BLL

Ånga

Tall Oil

25 Production units

38 Buer tanks

250 Streams

250 Measurements

2500 Variables

Fig. 8.6 Trend towards a nonlinear dynamic model

Part A 8.2

132 Part A Development and Impacts of Automation

Sim_c11

Grinding unit

20 40 60 80

Mill 4

100 120 140 160

Intervals during the week (interval = 1h)

Grades

0 20406080

Mill 3

100 120 140 160

Grades

0 20406080

Mill 2

100 120 140 160

Grades

0 20406080

Mill 1

100 120 140 160

Grades

Sim_c12

Sim_c21

Sim_c22

Sim_l1

Silo1

Silo2

d1_forecast

d2_forecast

Sim_l2

Sim_elec_cost

Sim_e

Fig. 8.7 Trend towards automated electrical energy man-

agement

to its design limitations results in either higher out-

put, more ﬂexibility, faster reaction or allows to install

smaller (and mostly cheaper) components to achieve the

same result.

A reduction of process equipment is also possible

if advanced production management algorithms are in

place. Manual scheduling of a process is hardly ever

capable to load all equipment optimally, and the so-

lution to a production bottleneck is frequently solved

by installing more capacity. In this case as well, the

application of an advanced scheduling algorithm may

show that current throughput can be achieved with less

equipment, or that current equipment can provide more

capacity than expected.

By applying advanced control and scheduling algo-

rithms, not only can an owner increase the productivity

of the installed equipment, but he may also be able to

reduce installed buffers. Intermediate storage tanks or

queues can be omitted if an optimized control scheme

considers a larger part of the production facility. In

addition to reducing the investment costs by reducing

equipment, the reduction of buffers also results in a re-

duction of work in progress, and in the end allows the

owner to run the operation with less working capital.

Looking at the wide impact of more precise control

algorithms (which in many cases implies more ad-

vancedalgorithms) on OEE, wecan easilyconclude that

once these capabilities in control system become more

easily available, users will adopt them to their beneﬁt.

Example: Thickness Control in Cold-Rolling Mills Us-

ing Adaptive MIMO Controller.

In a cold-rolling mill,

where a band of metal is rolled off an input coil, run

through the mill to change its thickness, and then rolled

onto an output coil, the torques of the coilers and the

roll position are controlled to achieve a desired output

thickness, uncoiler tension, and coiler tension. The past

solution was to apply single-loop controllers for each

variable together with feedforward strategies.

The approach taken in this case was to design an

adaptive multiple-input/multiple-output (MIMO) con-

troller that takes care of all variables. The goal was

to improve tolerance over the whole strip length, im-

prove quality during ramp-up/ramp-down, and enable

higher speed based on better disturbance rejection. Fig-

ure 8.8 shows the results from the plant with a clear

improvement by the new control scheme [8.2].

By applying the new control scheme, the operator

was able to increase throughput and quality, two inputs

of the OEE model shown in Fig.8.1.

Integrated Safety

The integration of processand automationbecomes crit-

ical in safety applications. Increasingly, safety-relevant

actions are moved from process design into the automa-

tion system. With similar motivations as we have seen

before, a plant owner may want to reduce installed pro-

cess equipment in favor of an automation solution, and

replace equipment that primarily serves safety purposes

by an emergency shutdown system.

Today’s automation systems are capable of fulﬁll-

ing these requirements, and the evolution of the IEC

61508 standard [8.3] has helped to develop a common

understanding throughout the world. The many local

standards have mostly been replaced by IEC 61508’s

Part A 8.2

Trends in Automation 8.2 Current Trends 133

Fig. 8.8 Cold-rolling mill controller comparison

safety integrity level (SIL) requirements. Exceeding the

scope of previous standards, ICE61508 not only deﬁnes

device features that enable them to be used in safety

critical applications, it also deﬁnes the engineering pro-

cesses that need to be applied when designing electrical

safety systems.

Many automation suppliers today provide a safety-

certiﬁed variant of their controllers, allowing safety

solutions to be tightly integrated into the automa-

tion system. Since in many cases these are specially

designed andtested variants ofthe general-purposecon-

trollers, they are perceived having a guaranteed higher

quality withlonger mean time between failures(MTBF)

and/or shorter mean time to repair (MTTR). In some

installations where high availability or high quality is

required without the explicit need for a certiﬁed safety

system, plant owners nevertheless choose the safety-

certiﬁed variant of a system to achieve the desired

quality attributes in their system.

A fully integrated safety system furthermore in-

creases planning ﬂexibility. In a fully integrated system,

functionality can be moved between the safety con-

trollers and regular controllers, allowing for a fully

scalable system that provides the desired safety level.

For more information on safety in automation please

refer to Chap.39.

Information Integration

Device and System Integration

Intelligent Field Devices and their Integration.

When

talking about information integration, some words need

to be spent on information sources in an automation

system, i.e., on ﬁeld devices.

Field devices today not only provide a process

variable. Field devices today beneﬁt from the huge

advancements in miniaturization, which allows man-

ufacturers to move measurement and even analysis

functions from the distributed control system (DCS)

into the ﬁeld device. The data transmitted over ﬁeld-

buses not only consists of one single value, but of

a whole set of information on the measurement. Quality

as wellas conﬁguration information can be read directly

from the device and can be used for advanced asset

monitoring. The amount of information available from

the ﬁeld thus greatly increases and calls for extended

processing capabilities in the control system.

Miniaturization and increased computing power

also allow the integration of ultrafast control loops on

Part A 8.2

134 Part A Development and Impacts of Automation

the ﬁeld level, i.e., within the ﬁeld device, that are not

feasible if theinformation hasto traverse controllers and

buses.

All these functions call for higher integration capa-

bilities throughout the system. More data needs to be

transferred not only from the ﬁeld to the controller, but

since much of the informationis notrequired on the pro-

cess control level but on the operations or even at the

plant management level, information needs to be dis-

tributed further. Information management requirements

are also increased and call for more and faster data

processing.

In addition to the information exchanged online, in-

telligent ﬁeld devices also call for an extended reach of

engineering tools. Since these devices may include con-

trol functionality, planning an automation concept that

spreads DCS controllers and ﬁeld devices requires en-

gineering tools that are capable of drawing the picture

across systems and devices.

The increased capabilities of the ﬁeld devices im-

mediately create the need for standardization. The

landscape that was common 20years ago, where each

vendor had his own proprietary integration standard,

is gone. In addition to the ﬁeldbus standards already

widely in use today, we will look at IEC 61850 [8.4]as

one of the industrial Ethernet-based standards that has

recently evolved and gained wide market acceptance in

short time.

Fieldbus. For some years now, the standard to commu-

nicate towards ﬁeld devices is ﬁeldbus technology [8.5],

deﬁned in IEC 61158 [8.6]. Allmajor ﬁeldbus technolo-

gies are covered in this standard, and depending on the

geographical area and the industry, in most cases one

or two of these implementations have evolved to be the

most widely used in an area. In process automation,

Foundation Fieldbus and Proﬁbus are among the most

prominent players.

Fieldbus provides the means for intelligent ﬁeld de-

vices to communicate their information to each other, or

to the controller. It allows remote conﬁguration as well

as advanced diagnostics information.

In addition to the IEC 61158 protocols that are

based on communication on a serial bus, the HART

protocol (highway addressable remote transducer pro-

tocol, a master-slave ﬁeld communication protocol) has

evolved to be successful in existing, conventionally

wired plants. HART adds serial communication on top

of the standard 4–20mA signal, allowing digital infor-

mation to be transmitted over conventional wiring.

Fieldbus is the essential technology to further inte-

grate more information from ﬁeld devices into complex

automation systems.

IEC 61850. IEC 61850 is a global standard for communi-

cation networks and systems in substations. It is a joint

International Electrotechnical Commission (IEC)and

American National Standards Institute (ANSI) stan-

dard, embraced by all major electrical vendors. In

addition to just focusing on a communication protocol,

IEC 61850 also deﬁnes a data model that comprises the

context of the transmitted information. It is therefore

one of the more successful approaches to achieve true

interoperability between devices as well as tools from

different vendors [8.7].

IEC 61850 deﬁnes all the information that can be

provided by a control function through the deﬁnition of

logical nodes. Substation automation devices can then

implement one or several of these functions, and deﬁne

their capabilities in standardized, extensible markup

language (XML)-based data ﬁles, which in turn can be

read by all IEC 61850-compliant tools [8.8].

System integration therefore becomes much faster

than in the past. Engineering is done on an object-

oriented level by linking functions together (Fig.8.9).

The conﬁguration of the communication is then derived

from these object structures without further manual en-

gineering effort.

Due to the common approach by ANSI and IEC,

by users and vendors, this standard was adopted very

quickly and is today the common framework in substa-

tion automation around the world.

Once an owner has an electrical system that pro-

vides IEC 61850 integration, the integration into the

plant DCS is an obvious request. To be able to not

only communicate to an IEC 61850-based electrical

system directly from the DCS, but also to make use of

all object-oriented engineering information is a require-

ment that is becoming increasingly important for major

DCS suppliers.

Wireless. When integrating ﬁeld devices into an au-

tomation system, the availability of standard protocols

is of great help, as we have seen in Device and Sys-

tem Integration. In the past this approach was very

often either limited to new plant installations where

cable trays were easily accessible, or resulted in very

high installation costs. The success of the HART pro-

tocol is mainly due to the fact that it can reuse existing

wiring [8.9].

Part A 8.2