Electricity + Control May 2015

DRIVES, MOTORS + SWITCHGEAR

AD Dc

– Analogue to Digital

– direct current PID – Proportional Integral Derivative

Abbreviations/Acronyms

The windings are driven by the switch output section which receives its command signal from a current loop. This prevents the drive from attempting to provide infinite output current in the event of a large position error. The positioning loop sets the final positioning accuracy by comparing the required position with the actual position. The position error is computed by comparing the target position of a bi-directional input counter, driven by the step and direction signals with another bi-directional counter driven by the feedback encoder. Controller filtering uses a PID (Proportional, Integral and Deriva- tive) algorithm. My intention is to publish a further article to amplify the drive operation principles. Dynamometer operation (Refer to Figure 2 ) − this follows standard practice by coupling the motor on test to another motor which acts as a generator to load the test motor. In this case (see Test set-up ) a suitable sized dc brush motor and motor drive were to hand.

Figure 2: Test setup schematic.

BRUSHLESS MOTORS, GEARBOXES AND DRIVES

Supply Voltage 20 - 40V Output 3 Phase 5A Continuous 10A peak Industry standard step and direction input position signals Companion system controllers supplied by us Free tuning software

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