UM0522
Motor control operations
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Table 5.
"3-phase BLAC/DC (trapezoidal)" basic parameters
Parameter name
Description
Poles pairs
The number of pole (north/south) pairs in the motor
Speed regulation
The manner in which to run the motor, either open loop (without speed
regulation) or closed loop (with speed regulation)
Driving mode
The motor driving mode, current mode or voltage mode
Current bus limitation
The software current limitation value (only in voltage mode), if the current
flowing inside one (of three) phases of the motor reaches this value
overcurrent is not generated but the pwm is managed to limit the current at
this level.
Detection mode
The back EMF (BEMF) detection mode (rotor position),
only sensorless
control is allowed in this evaluation board
Alignment phase
Final duty cycle
The percentage of final duty cycle applied at the end of alignment phase
(only in voltage mode)
Final current
The value of current flowing inside the motor at the end of the
“alignment
phase”
(only in current mode)
Alignment duration
The duration of the
“alignment phase”
in milliseconds (ms)
Acceleration phase
Mechanical
acceleration rate
The mechanical acceleration rate of the rotor during the ramp up in RPMs
(or Hz) per second (alternate between RPM and Hz settings by clicking on
the “RPM” button)
Duty cycle
The duty cycle percentage during the ramp up (only in voltage mode)
Current reference
The value of current flowing inside one (of three) phases of the motor at the
end of the
“acceleration phase”
(only in current mode)
Number of Z events
before auto-switched
mode
The number of consecutive Z events that occur before the microcontroller
runs the motor in autoswitched mode
Electrical frequency
Minimum
The minimum target rotor frequency in closed loop, expressed in Hz
Maximum
The maximum target rotor frequency in closed loop, expressed in Hz
Run settings
From RV1
When the “From RV1” checkbox is selected: duty cycle value is defined by
the RV1 potentiometer (only for voltage mode), or current reference is
defined by the RV1 potentiometer (only for current mode), or target speed
is defined by the RV1 potentiometer (only for closed loop) if this box is
unchecked, the above parameters are set by the user.
Duty cycle
The duty cycle percentage when the motor is run in “open loop” “voltage
mode”
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