AGL Loy Yang

AGL Loy Yang operates the largest open-cut coal mine in the southern hemisphere, producing approximately 30 million tonnes of brown coal annually to fuel its 2,210MW power station in Victoria's Latrobe Valley. The mine's conveyor network — spanning over 25 kilometres and running continuously — transfers coal from the mine floor to a surface bunker with only 20 hours of generation capacity, leaving no buffer for unplanned stoppages. The legacy drive systems, based on water-cooled eddy-current coupling (ECC) technology, were reaching their operational limits: they could not support power demands from extended conveyors, were increasingly difficult to maintain, and delivered unreliable control performance that risked costly generation outages.

Working in close collaboration with AGL Loy Yang's engineering team, Rockwell Automation developed a modular drive solution built around the Allen-Bradley PowerFlex 7000 medium voltage AC drive. The drives feature Direct-to-Drive technology, eliminating the need for isolation transformers and reducing the overall equipment footprint. Each conveyor was fitted with a self-contained, stainless steel IP65-rated enclosure housing a 6.6kV PowerFlex drive, complete with an integrated air-conditioning system for thermal management. Nine drive packages were deployed progressively, with each new unit engineered to synchronise seamlessly with the remaining ECC drives already in service. Integration extended through the existing PLC5 and ControlLogix infrastructure to the mine's SCADA system, with locally mounted Allen-Bradley electronic operator interfaces enabling diagnostics without exposing drives to the mine environment.

The phased drive upgrade delivered measurable operational improvements across the Loy Yang Mine conveyor network:

• Minimised unplanned downtime — reduced production stoppages and breakdowns that had previously threatened the 20-hour coal buffer feeding both power stations
• Elimination of isolation transformers — Direct-to-Drive technology removed a significant maintenance and space overhead from each drive installation
• Reduced maintenance burden — fewer components compared to ECC technology decreased the number of potential failure points across the 25km+ conveyor system
• Advanced diagnostics — SCADA-linked EOIs gave site personnel remote and local access to drive health data without opening enclosures
• Portable, reusable drive packages — self-contained units can be redeployed across conveyors, improving flexibility as the mine continues to expand

• Gradual, phased rollouts protect continuous operations — replacing legacy drives incrementally alongside existing ECC systems allowed Loy Yang to modernise without halting coal supply to the power stations.
• Drive portability reduces long-term capital exposure — designing self-contained, removable enclosures means equipment can follow operational need rather than being fixed assets tied to single conveyors.
• Eliminating transformers simplifies both footprint and maintenance — specifying transformerless drive technology at the design stage yielded compounding benefits in space, cost, and reliability.
• Early vendor involvement shapes better engineering outcomes — Rockwell Automation's participation from design through to installation enabled tighter integration with the existing SCADA and control architecture.
• A long-term vendor relationship lowers integration risk — accumulated site knowledge meant subsequent drive packages became routine upgrades rather than complex projects.