Hello,
I just unboxed my new FRDM-KV31F and FRDM-MC-LVBLDC motor kit.
I preformed the following actions:
- Installed the FRDM-MC-LVBLDC on top of the FRDM-KV31F board
- Connected a small drone motor to the motor connection header
- Connected a 12V bench power supply to the FRDM-MC-LVBLDC
- The red/blue led started blinking (as expected)
- Connected the USB cable. A USB drive was detected in by windows with some HTML files and a driver in it.
- Started Kinetis Motor Suite
- Connected to the target
- Two faults are preventing me from proceeding past step 2:
Current Sensor Calibration Fault
ADC Offset Fault
If I remove the FRDM-MC-LVBLDC shield and restart the KV31F, it still shows the fault with the shield removed.
I tried another power supply to verify that I had a stable 12 VDC source to the FRDM-MC-LVBLDC
It was measured at 12.2 V.
Both parts were purchased from digi-key. Perhaps I received some bad hardware? I paid over $70 with two day shipping to get started on this project and I can't get the motor to spin!
I searched google and the NXP community forums and found no one else with these problems. The Kinetis SDK provides some documentation for the faults.
6.2.5 struct DSM_nonClrFaults_t::DSM_nonClrFaultsBits_s
Drive state-machine non-clearable faults bits structure.
Data Fields
bitfield_t __pad0__: 5 unused bitfields
bitfield_t adcFault: 1 B0.3 DSM ADC offset fault on phase A, B or C bitfield
bitfield_t calibration←- Fault: 1 B0.2 DSM current sensors calibration fault bitfield
I checked the voltage on each motor connection to ground, and they are as follows:
Phase A - Ground : 0.640 Vdc
Phase B - Ground : 0.640 Vdc
Phase C - Ground : 0.640 Vdc
Phase A - Phase B : 0.00 Vdc
Phase B - Phase C : 0.00 Vdc
Phase C - Phase A : 0.00 Vdc
Any suggestions?
Thanks,
Jeremy
Solved! Go to Solution.
Jeremy,
You're using the wrong board. The KMS kit will work with FRDM-MC-LVPMSM, not LVBLDC.
The LVPMSM board is essential for KMS because it is the board that has the current-sensing shunts and op-amps necessary for field-oriented control. The LVBLDC board, on the other hand, is designed for trapezoidal control and does not have the needed circuitry.
I'm sorry about this confusion. My recommendation: return the LVBLDC and exchange an LVPMSM.
Eduardo Viramontes
Jeremy,
You're using the wrong board. The KMS kit will work with FRDM-MC-LVPMSM, not LVBLDC.
The LVPMSM board is essential for KMS because it is the board that has the current-sensing shunts and op-amps necessary for field-oriented control. The LVBLDC board, on the other hand, is designed for trapezoidal control and does not have the needed circuitry.
I'm sorry about this confusion. My recommendation: return the LVBLDC and exchange an LVPMSM.
Eduardo Viramontes
Eduardo,
Thanks for the info!
Will the FRDM-MC-LVPMSM work with with a sensorless velocity setup with a 3 phase BLDC motor?
Thanks,
Jeremy
Jeremy,
Yes the FRDM-MC-LVPMSM board will be able to control the sensorless velocity of a BLDC motor. BLDC motors can be considered a subset of PMSM motors. The KMS application will use sensorless FOC instead of sensorless six-step.
I also sometimes receive a DC Bus under-voltage.