According to Jonathan Thomas, Global Product Specialist for Material Handling with ABB Australia, the traditional way of controlling multiple motors on a conveyor system is flawed because it doesn’t address issues regarding belt tension and stress.
“In the past, you’d purchase a motor that you could control, and then have the next motors you add match those functions, such as speed and torque,” he says. “However, that’s assuming that the belts will have the same characteristics, and they don’t. Belts are susceptible to different variables such as stretching and bends or twists. This makes it difficult when you’re trying to synchronise the motors.”
Which is the reason why ABB developed the Mining Conveyor Control Program (MCCP), a software package designed to ensure the safe synchronisation of motors and streamlined control over all drive functions in a conveyor system. Importantly, the MCCP is open to every control system, and has been designed to run directly on the control board of its low or medium voltage variable-speed drives.
The MCCP software allows for parameter setting of essential drive control functions including start/stop, mechanical brake control, load sharing between motors and pulleys, acceleration and deceleration, as well as speed and torque limits.
“Having control over all aspects of the conveyor drives will help optimise the belt life,” says Jonathan. “You can then optimise the throughput of the conveyor because you can work it a little bit harder without worrying about damaging the belts.”
Previously, these functions would have to be custom developed for individual applications in an overriding PLC program.
“The MCCP simplifies this, bypassing the need to program it in the PLC, thus translating to savings in time and cost,” says Jonathan. “It also ensures all connected frequency converters apply the same torque to the conveyor. Thus, any defined load sharing between different pulleys can be adjusted.”
Miners can also benefit from the ABB MCCP digital twin, a conveyor simulation model that can be deployed to solve complex tasks. “Any kind of optimisation of your conveyor system will bring savings and benefits – often these are the most heavily maintained pieces of equipment out on mine sites,” says Jonathan. “MCCP has been designed as a tool that can help miners get the best performance out of their conveying systems and equipment.” In fact, the ABB MCCP concept is already running on several mine sites around Australia. “The feedback we’ve received has been very positive,” says Jonathan. “Particularly around the longevity of the belts.”
Key benefits of the MCCP include:
- Significant reduction in belt slip
- Seamless high load starting
- Low mechanical stress
- Low mechanical wear
- Low engineering effort
- Easy implementation
To summarise, Jonathan mentions the sustainability benefits that can come with running a conveyor system more efficiently. “You will get a slight reduction in energy use, but more importantly, if you’re increasing the life of the equipment, you’re doing your little bit for the sustainability of the environment because you’re not wasting resources or using them too fast.”
Previously pubished in the Australian Mining newsletter - The benefits of improving motor control on mining conveyors - Australian Mining
