ROLLING MILL DRIVE CONTROLLER

The rolling mill controller uses the latest in digital instrumentation technology, providing sophisticated control and fault annunciation.

The control system consists of separate on/off and drive controllers. Both of these are based on the SC2 SOPC core, built into a high density ALTERA FPGA (ACEX 1K100QC208-3) containing 100,000 gates and operating at 20 MHz. Both controllers communicate with each other on a high speed parallel link

The on/off controller can control upto 192 devices, such as blowers, pumps, solenoids etc, sufficient for most single stand mills.

The drive controller controls the DC motors on the coiler, decoiler and mill stand using closed loop phase control on their armature and field SCR bridges. Precise tension control is achieved either by direct tension feedback from a tensiometer or armature current feedback with the setpoint compensated for inertia, draft and friction.

3 Nos LCD VGA display units are present on the console desk. These display fault annunciation, status of stand motors and ancilliary equipment , in text mode and speed, armature current and field current in real-time graphic mode.

• No temperature drift of tuning parameters
• Component count dramatically reduced resulting in higher Mean Time Between Failure (MTBF)
• Enclosure density and size dramatically reduced.
• Fewer wiring connections.
• All tuning and adjustments are made in software thus hardware adjustments which are arror prone and not easily reversible are not required

• SCR failure detection.
• Fuse failure detection and identification.
• Strip breakage detection.
• Inertia, draft and friction compensation.
• Operation in Field weakening region.
• Non regenerative 2 quadrant control using single bridge or regenerative 4 quadrant control using a dual bridge.
• Accurate controller tuning to optimize response time, over-shoot, under-shoot, settling time and steady state error.
• On-site re-programming by serial communication with another computer.
• Automatic gage control.
• Remote operation and monitoring via serial link
• Tension, speed and roll gap for each pass can be set from downloaded production plan.
• Productivity parameters such as up/down time, breakages, quantity of material rolled etc can be monitored.