In machine tools, during processing, some operations can result in transient power peaks. In is an undesirable phenomenon, because it loads the electricity supply network and cause high current surges which lead to higher power transmission losses. Factories often contract the peak power available with the utility company and systematic exceeding of the contracted value may result in fines.
The instantaneous value of the power peaks can exceed the double of the average power consumption and is typically caused by starting electric motors. One of the most powerful motor in a machine tool are the ones which power the spindle subsystems. The problem becomes even more apparent in multi-spindle machines, because the spindle start-up may occur simultaneously, multiplying the effect. In my newest paper I investigate possible means of peak suppression by adopting optimal motor torque control during acceleration and deceleration phases and a synchronization algorithm to avoid simultaneous start of multiple spindles.
The paper titled “Electric load management in spindle run-up and run-down for multi-spindle machine tools via optimal power-torque trajectories and peak load synchronization” was published in the The International Journal of Advanced Manufacturing Technology and can be found under the address: https://doi.org/10.1007/s00170-017-1341-7.
An open access, read-only version of the paper available at: http://rdcu.be/yAmj
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