Adding a variable frequency drive (VFD) to a compatible Bucyrus machine has a positive impact on the bottom line. Costly DC motors are replaced by more efficient brushless AC motors which require less maintenance and have a longer service life. A Un-A-Hauler® with VFD control transports more tonnes per shift. A VFD-equipped Vers-A-Trac® completes longwall moves faster. Feeder breakers with VFD allow hauler operators to unload faster without fear of costly downtime. And in continuous miners, VFD traction control improves non-productive move times as well as sump and cut performance. Bucyrus has applied VFD controls to many of its room & pillar products. Cross-functional design teams with expertise in machine design, control and mining have applied VFD technology to Bucyrus battery-powered haulers and shield movers as well as to continuous miners and feeder breakers, improving performance and cutting operating costs.
The VFD controls used on the Un-A-Hauler and Vers-A-Trac are manufactured exclusively for Bucyrus. Robustly designed for mine-duty applications, the compact modules control AC traction and pump motors. Advanced flux vector control, autocheck system diagnostics, advanced I/O protection, self-characterisation, and a network of data-sharing system modules ensure safe operation and optimal productivity.
Adding a VFD control to Bucyrus rubber-tyred battery-powered equipment increases speed, manoeuvrability and responsiveness while allowing the operator to monitor machine performance with the on-board machine management system. This means faster discharge times for the Un-A-Hauler and quicker shield-loading times for the Vers-A-Trac. Regenerative braking saves power and reduces brake system wear and maintenance.
Bucyrus feeder breaker performance also benefits from VFD conveyor control. The VFD monitors the feeder load to prevent jams, avoiding costly downtime. If the breaker load exceeds the motor rating, the control reduces chain speed. If the excessive load continues, a jam-clearing cycle is started. This minimises equipment damage such as broken or bent chain flights, premature wear on the chain and sprockets, and shock loading of the gear boxes. It also allows haulage operators to unload their cars more quickly.
The addition of a VFD to a Bucyrus continuous miner increases speed, motor torque and motor torque control, allowing faster repositioning and improved sump and cutting performance. The continuous miner VFDs control the AC motors which power the left and right tracks. The VFD control is backward compatible with existing continuous miners. The AC drives feature motor overload protection, the proven CAN communication interface, enhanced diagnostics and closed loop control to ensure that the continuous miner runs at peak efficiency.
