ABB ac160 MA-2007-06 Power Systems

ABB ac160 MA-2007-06 Power Systems

Description

ABB Power Systems is one of the world’s leading providers of infrastructure for controlling combined cycle power stations and waste-to-energy plants. Such a plant control infrastructure includes several hardware parts consisting of controllers, input/output-boards and communication devices as well as many software components to engineer, run, observe and analyze the power plant. A power plant control system has to satisfy a broad variety of different needs, from the efficient and reliable control of the turbines and associated supporting functions (such as lube oil) to easy configuration and operation as well as to sophisticated analysis functions addressing technical and economical aspects.

Problem Statement 

Due to high investment costs, the technical management of power plants is a slowgoing business with long life-cycles. Thus, a considerable amount of hardware devices currently in use are tens of years old. For future applications within ABB Power Systems it will be necessary to connect a controller of the newest series used within ABB, Control IT AC800M, with an older controller of the type Advant Controller 160 (AC160). The problem is that these two controllers do not share a fast communication interface of similar type and therefore cannot communicate directly. The standard communication intended for AC160 is Advant Fieldbus 100 (AF100). However, AC800M can support a whole range of buses except for AF100. As a consequence, the communication must be implemented using some relaying technique.

The Use of OPC 

It was decided in advance to realize the relaying connection using OPC. This solution was chosen because OPC is an open standard and very common in process and automation industry. Furthermore, this solution offers a high potential to be used for similar problems, since a lot of devices support this specification. However, OPC is normally not used for fast controller-to-controller communication but for slower visualization and logging purposes and there is no performance data available for this kind of connection. The use of OPC is therefore both challenging as well as interesting to gain more insights and know-how.

The goals of this Master’s Thesis are stated as follows: 

• Setup and evaluation of a test environment 

• Setup of test systems 

• Theoretical and practical evaluation of the test systems concerning performance, availability and reliability. 

• Identification of improvements and different approaches 

• Comparison with alternatives

Programmable Logic Controllers 

This section informs about the two controllers involved and about the controller that has to be replaced. Please notice that we use the term controller equivalent to programmable logic controller (PLC) throughout our Master’s Thesis.

Control IT AC800M 

Control IT AC800M is the most current controller series used within all of ABB, introduced in 2001 [9]. It strikes with its small outline and offers modern communication interfaces. For our tests we were provided with a processor module PM864A which contains a Motorola MPC862 microprocessor running at 96 MHz [10]. In addition to two EIA-232 interfaces, the processor module of AC800M offers two built-in 10 Mbit/s standard Ethernet ports, used for instance to connect to the engineering computer.

Advant Controller 450 (AC450) 

AC450 is the controller to be replaced by the new generation. Its processor module is built up around a Motorola 68040 microprocessor running at 25 MHz [8]. While its performance is quite limited, AC450 also lacks of modern communication interfaces and standards like Ethernet, which become more and more important.