High-performance applications with extremely fast control algorithms

– Cycle times ranging from 100 μs (microseconds) for fast control loops to several seconds for long-term transient operation require specialised control equipment.

Dual-core processor units combine these high-speed controls with low-speed process control tasks normally performed by stand-alone PLC (Programmable Logic Controller) units.

The dual-core processor unit takes the technology a step further by combining these high-speed control and low-speed process control tasks normally performed by a separate PLC (Programmable Logic Controller) unit.

The AC 800PEC embedded system is unique in the field of industrial process controllers for its robust and flexible architecture and integrated standard communication functions.

The AC 800PEC is the ultimate way to fulfil high demands.

The AC 800PEC offers a unique combination of functions for demanding applications:

– Short cycle times, down to 100 μs

– High processing power

– Fast communication and input/output via optical links

– Programming tools:

– System engineering using ABB Control Builder’s IEC61131-3 language.

Compact and specialised

– Product and control development using MATLAB®/Simulink® for model-based design, easily bridging the gap from simulation to implementation

– Fully integrated with ABB Ability™ System 800xA

– Innovative and flexible use of FPGAs to include protocol and application functionality in the device without creating an additional processor load

– Optical communications

– Industrial grade hardware with no moving parts

– Long life and easily upgradable

– Robust file-dependent system, unaffected by power failures

Built for power control in the process industry

ABB has global expertise and know-how in the field of process control for industrial, marine and other applications.

As a result, the AC 800PEC is a key controller for ABB industrial applications www.abb-drive.com as well as third-party products and systems.

The AC 800PEC is an efficient and flexible controller family. With short cycle times, fast (input/output) I/O,

processing power and advanced control using MATLAB®/Simulink®:

– Increased process quality and throughput

– Savings in development and engineering costs

– Reduced product energy consumption

– Reduced time-to-market for development projects

– Savings in engineering and software development labour and resources

– Improved return on assets (ROA)

– Hardware back-up trips for integration with fast COMBI I/Os

Modular structure of the AC 800PEC control system

The modular structure of the system means that it can be adapted to any size of application, from the largest industrial equipment and propulsion systems to compact products where space and cost are critical.

All over the world, thousands of processors have proved their worth in a wide range of extremely demanding applications.

Powerful hardware for efficient high-speed processing

The AC 800PEC combines the floating-point performance of a CPU with the flexibility and high-speed capability of an FPGA.

The system is divided into three performance levels covering different cycle times. Control tasks are assigned depending on their speed requirements:

– Very fast tasks, down to 25 nanoseconds (nanoseconds for FPGA tasks)

– Fast tasks down to 100 μs (microseconds for Matlab/Simulink tasks)

– Slow tasks down to 1 ms (milliseconds for control tasks)

The hardware architecture of the AC 800PEC is complemented by a three-level software architecture.

To support short processing cycles, the AC 800PEC offers a fast I/O system.

Depending on the speed of the I/O connections, data throughput times can be less than 100 μs, including the time required to read, process, write and transmit signals.

Implementing the AC 800PEC software at three performance levels provides excellent control and communication capabilities.

The following software packages have been developed to support each specific high power rectifier application.

Aluminium applications

– AC 800PEC unit controller ↔ AC 800PEC master controller communicates via PEC – PEC fibre optic link (100 μs)

– Can be independent of the main controller control unit

– Allows emergency operation (full smooth current control in emergency mode without AC 800PEC, only in combination with DCS800 pre-magnetisation)

– Predictive maintenance functions can be included

– Open circuit, overcurrent, undervoltage and overvoltage protection packages included in software

– Newly developed OPC (Open Circuit Protection) stand-alone PLC (Programmable Logic Controller) that can be used in conjunction with AC 800PEC main controller functions or as a stand-alone protection during main board maintenance

– Controlled shutdown in the event of an event without immediate tripping → reduced disruption to the production process

– Potline load fluctuation detection and load shedding integrated into the application software

– Load tap converter fast tap function to prevent DC current overloads during disturbances

– Special Potline-to-Earth Resistance Measurement System (PERMS) based on the AC 800PEC series

– Maximum power regulation

– Prevents excessive power consumption and supports your generator

– Maximum DC voltage regulation to stabilise the process

Arc Furnace Applications

– Stable arc detection

– Different control modes (constant current, constant power or constant resistance)

– Quick connection to Power Quality Systems (PQS)

Includes ELREG (electrode regulation; control of the anode hydraulic system) function:

– Manual electrode control (analogue or digital)

– Electrode quick lift function (with or without separate quick lift valve)

– Automatic arc extinguishing function

– Automatic re-arc function

– Adaptive electrode control according to furnace conditions or heating stage

– Stacked integral control circuit

– Voltage fluctuation measurement (stability index calculation)

– Arc detection/protection of the furnace roof

– Protection of the furnace top from arcs during arc extinguishing

– Hydraulic oil pressure monitoring and electrode protection

– Collapse detection

– High-pressure detection

– Control logic for backpressure valves

– Voltage monitoring to ground

– Voltage monitoring at the top of the furnace

– Automatic raising of the electrode after a furnace shutdown command (distance or position selectable)

– Shut-off valve control

– Electrode speed limitation to protect electrode and arm

– Future functions

– Automatic proportional valve linearisation

Check

– Automatic proportional valve linearisation

– Dynamic voltage setpoint control for stable melting processes