MCF8329EVM: MPET either does not run, gives a fault, or makes a high pitched squeal

Neil

Part Number: MCF8329EVM
Other Parts Discussed in Thread: MCF8315A

I have an MCF8329EVM board, trying to get a motor spinning. When running MPET it either does not run at all (no attempt to even switch the MOSFETs from what I see), or gives me an MPET fault.

I tried manually entering the inductance, resistance and BEMF constant, based on the motor datasheet and measuring as per: https://www.tek.com/en/documents/primer/making-measurements-on-3-phase-motor-drives-with-an-oscilloscope

Running MPET after this causes a high pitched squeal, but no motor movement. At this point I turned off the power, since there is no 'cancel MPET' option in the GUI.

I am running the latest GUI Version: 0.1.12

I thought it might be due to using a lower current motor than the dev board is intended for, so changed the sense resistor for a 22mOhm. I found the advance option to tell it I have this value, but it made no difference to the results. The motor is 3A rated, we tried the 4A MCF8315A, but it cut-out after 15 minutes at full speed. The end application will have a maximum ambient temperature of 60C, so I am inclined not to trust drivers with internal FETs, cost is not a barrier, but failure to spin definitely is.

I have tried running it with an unloaded motor, it did spin briefly, and get results for Ke, Kp and Ki. But the Ke value is lower than the one I measured above. It didn't read resistance or inductance, so I added the results I measured, but then it went back to squealing and not moving. It doesn't register a fault at this point, so I have to power cycle.

I see from others with the same issue in https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1306649/mcf8329evm-mpet-not-working and https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1311658/mcf8329evm-troubleshooting-faults there is a video guide available, but the links given in those support tickets have expired, so I can't view it.

Can I get access to this video? What else should I be doing?

As an aside, the GUI contradicts the User Guide with the position of the switches, the GUI only tells you to set SW1 to SW3, but there are 4 switches. The photo in the GUI shows 4 switches, but puts them in an off state (which the description contradicts). I have setup as per the user guide, which looks correct.

Thanks.

1 month ago

0 Venkatadri Shantaram84961 1 month ago

TI__Expert 4540 points

Hi Neil,

What is R, L and KE you manually measured?

MCF8329 R, L is not supported by MPET, KE and Kp, Ki are supported.

Can you share the JSON used to run the MPET?

Thanks and Best Regards,

Venkatadri S

0 Neil 1 month ago in reply to Venkatadri Shantaram84961

Prodigy 30 points

Hi Venkatadri, thanks for the reply.

Realised I linked to the wrong page above, the measurements were made following this TI guide: https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1213224/faq-what-are-motor-parameters-why-are-they-needed-and-how-do-i-measure-them

The motor specs are:

0.501 ohms PH-PH, so 0.25 ohms RPH
0.39 mH PH-PH, so 0.195mH LPH, call it 0.2mH
No spec for BEMF

I measured:

0.32 ohms PH-PH (using bench DMM), 0.4 ohms (using a cheap handheld LCR)
0.35mH (using cheap LCR meter)
EPH 3.3V, TE 9.4ms, so Ke = 17.9 mV/Hz (using scope and equation given in link above)

I used the datasheet values for the resistance and inductance (divided by 2), as I assumed it would be a better average for all motors, and the measured value for Ke.

The MPET result gave me 0 for resistance and inductance (but if not supported makes sense), Ke 8mV/Hz, Kp 0.202, Ki0.202.

I tried to run the motor with both 8 and 18 for Ke, but neither seemed to work. That said, I was trying to run MPET again. Maybe I don't need to?

I didn't save the JSON, I'll try again tomorrow.

0 Neil 1 month ago in reply to Neil

Prodigy 30 points

I found the 22mOhm setting was not being accepted, hovering over the input gave me this:

Would be better if it made it more obvious I had entered a invalid value, make the box red so I have a clue?

Set it to 22.1mOhm, but the motor still does not complete MPET. Tried with sense gain of 40 and 20.

Tried starting with the values it gave me the only time it ran (see previous reply), but it still doesn't move at all. Sometimes silent, sometimes squealing. I can see it switching the FETs with the scope, but no movement.

The motor is a Maxon 449464, 24V version: https://www.maxongroup.com/medias/sys_master/root/8882557616158/EN-21-272.pdf

Here is the JSON, it wouldn't let me upload the file, so pasted the code.

{
"signature":"oneui-register-data",
"data":[
[
{
"idx":0,
"id":"ISD_CONFIG",
"value":"0x64A2D4A1",
"addr":"0x00000080"
},
{
"idx":1,
"id":"REV_DRIVE_CONFIG",
"value":"0x48300000",
"addr":"0x00000082"
},
{
"idx":2,
"id":"MOTOR_STARTUP1",
"value":"0x10A64CC0",
"addr":"0x00000084"
},
{
"idx":3,
"id":"MOTOR_STARTUP2",
"value":"0x2D81C007",
"addr":"0x00000086"
},
{
"idx":4,
"id":"CLOSED_LOOP1",
"value":"0x1D7181B8",
"addr":"0x00000088"
},
{
"idx":5,
"id":"CLOSED_LOOP2",
"value":"0x0AAD4B4B",
"addr":"0x0000008A"
},
{
"idx":6,
"id":"CLOSED_LOOP3",
"value":"0x23800003",
"addr":"0x0000008C"
},
{
"idx":7,
"id":"CLOSED_LOOP4",
"value":"0x4AB29068",
"addr":"0x0000008E"
},
{
"idx":8,
"id":"REF_PROFILES1",
"value":"0x00000000",
"addr":"0x00000094"
},
{
"idx":9,
"id":"REF_PROFILES2",
"value":"0x00000000",
"addr":"0x00000096"
},
{
"idx":10,
"id":"REF_PROFILES3",
"value":"0x00000004",
"addr":"0x00000098"
},
{
"idx":11,
"id":"REF_PROFILES4",
"value":"0x00000000",
"addr":"0x0000009A"
},
{
"idx":12,
"id":"REF_PROFILES5",
"value":"0x00000000",
"addr":"0x0000009C"
},
{
"idx":13,
"id":"REF_PROFILES6",
"value":"0x00000000",
"addr":"0x0000009E"
}
],
[
{
"idx":0,
"id":"FAULT_CONFIG1",
"value":"0x465A31A6",
"addr":"0x00000090"
},
{
"idx":1,
"id":"FAULT_CONFIG2",
"value":"0x71422888",
"addr":"0x00000092"
}
],
[
{
"idx":0,
"id":"INT_ALGO_1",
"value":"0x0946047D",
"addr":"0x000000A0"
},
{
"idx":1,
"id":"INT_ALGO_2",
"value":"0x020082E3",
"addr":"0x000000A2"
}
],
[
{
"idx":0,
"id":"PIN_CONFIG",
"value":"0x40032309",
"addr":"0x000000A4"
},
{
"idx":1,
"id":"DEVICE_CONFIG1",
"value":"0x00100001",
"addr":"0x000000A6"
},
{
"idx":2,
"id":"DEVICE_CONFIG2",
"value":"0x03E8C00C",
"addr":"0x000000A8"
},
{
"idx":3,
"id":"PERI_CONFIG1",
"value":"0x69845CC0",
"addr":"0x000000AA"
},
{
"idx":4,
"id":"GD_CONFIG1",
"value":"0x0000807B",
"addr":"0x000000AC"
},
{
"idx":5,
"id":"GD_CONFIG2",
"value":"0x00000400",
"addr":"0x000000AE"
}
],
[
{
"idx":0,
"id":"GATE_DRIVER_FAULT_STATUS",
"value":"0x00000000",
"addr":"0x000000E0"
},
{
"idx":1,
"id":"CONTROLLER_FAULT_STATUS",
"value":"0x00000001",
"addr":"0x000000E2"
}
],
[
{
"idx":0,
"id":"ALGO_STATUS",
"value":"0x00000004",
"addr":"0x000000E4"
},
{
"idx":1,
"id":"MTR_PARAMS",
"value":"0x00000000",
"addr":"0x000000E6"
},
{
"idx":2,
"id":"ALGO_STATUS_MPET",
"value":"0x02000000",
"addr":"0x000000E8"
}
],
[
{
"idx":0,
"id":"ALGO_CTRL1",
"value":"0x20000000",
"addr":"0x000000EA"
}
],
[
{
"idx":0,
"id":"ALGO_DEBUG1",
"value":"0x80000000",
"addr":"0x000000EC"
},
{
"idx":1,
"id":"ALGO_DEBUG2",
"value":"0x00000000",
"addr":"0x000000EE"
},
{
"idx":2,
"id":"CURRENT_PI",
"value":"0x00000000",
"addr":"0x000000F0"
},
{
"idx":3,
"id":"SPEED_PI",
"value":"0x00000000",
"addr":"0x000000F2"
},
{
"idx":4,
"id":"DAC_1",
"value":"0x00000000",
"addr":"0x000000F4"
}
],
[
{
"idx":0,
"id":"ALGORITHM_STATE",
"value":"0x00120014",
"addr":"0x00000196"
},
{
"idx":1,
"id":"FG_SPEED_FDBK",
"value":"0x7FFFFFFF",
"addr":"0x0000019C"
},
{
"idx":2,
"id":"BUS_CURRENT",
"value":"0x00000000",
"addr":"0x0000040E"
},
{
"idx":3,
"id":"PHASE_CURRENT_A",
"value":"0x00000000",
"addr":"0x0000043C"
},
{
"idx":4,
"id":"PHASE_CURRENT_B",
"value":"0x00000000",
"addr":"0x0000043E"
},
{
"idx":5,
"id":"PHASE_CURRENT_C",
"value":"0x00000000",
"addr":"0x00000440"
},
{
"idx":6,
"id":"CSA_GAIN_FEEDBACK",
"value":"0x00000000",
"addr":"0x00000450"
},
{
"idx":7,
"id":"VOLTAGE_GAIN_FEEDBACK",
"value":"0x00000000",
"addr":"0x00000458"
},
{
"idx":8,
"id":"VM_VOLTAGE",
"value":"0x033B5E0E",
"addr":"0x0000045C"
},
{
"idx":9,
"id":"PHASE_VOLTAGE_VA",
"value":"0x02A45DA6",
"addr":"0x00000460"
},
{
"idx":10,
"id":"PHASE_VOLTAGE_VB",
"value":"0x029F2B6F",
"addr":"0x00000462"
},
{
"idx":11,
"id":"PHASE_VOLTAGE_VC",
"value":"0x02A1C48B",
"addr":"0x00000464"
},
{
"idx":12,
"id":"SIN_COMMUTATION_ANGLE",
"value":"0x00000000",
"addr":"0x000004AA"
},
{
"idx":13,
"id":"COS_COMMUTATION_ANGLE",
"value":"0x00000000",
"addr":"0x000004AC"
},
{
"idx":14,
"id":"IALPHA",
"value":"0x00000000",
"addr":"0x000004CC"
},
{
"idx":15,
"id":"IBETA",
"value":"0x00000000",
"addr":"0x000004CE"
},
{
"idx":16,
"id":"VALPHA",
"value":"0x00000000",
"addr":"0x000004D0"
},
{
"idx":17,
"id":"VBETA",
"value":"0x00000000",
"addr":"0x000004D2"
},
{
"idx":18,
"id":"ID",
"value":"0x00000000",
"addr":"0x000004DC"
},
{
"idx":19,
"id":"IQ",
"value":"0x00000000",
"addr":"0x000004DE"
},
{
"idx":20,
"id":"VD",
"value":"0x00000000",
"addr":"0x000004E0"
},
{
"idx":21,
"id":"VQ",
"value":"0x00000000",
"addr":"0x000004E2"
},
{
"idx":22,
"id":"IQ_REF_ROTOR_ALIGN",
"value":"0x00000000",
"addr":"0x0000051A"
},
{
"idx":23,
"id":"SPEED_REF_OPEN_LOOP",
"value":"0x00000000",
"addr":"0x00000532"
},
{
"idx":24,
"id":"IQ_REF_OPEN_LOOP",
"value":"0x00000000",
"addr":"0x00000542"
},
{
"idx":25,
"id":"SPEED_REF_CLOSED_LOOP",
"value":"0x00000000",
"addr":"0x000005D0"
},
{
"idx":26,
"id":"ID_REF_CLOSED_LOOP",
"value":"0x00000000",
"addr":"0x0000060A"
},
{
"idx":27,
"id":"IQ_REF_CLOSED_LOOP",
"value":"0x00000000",
"addr":"0x0000060C"
},
{
"idx":28,
"id":"ISD_STATE",
"value":"0x00000000",
"addr":"0x000006B0"
},
{
"idx":29,
"id":"ISD_SPEED",
"value":"0x00000000",
"addr":"0x000006BA"
},
{
"idx":30,
"id":"IPD_STATE",
"value":"0x00000000",
"addr":"0x000006E4"
},
{
"idx":31,
"id":"IPD_ANGLE",
"value":"0x00000000",
"addr":"0x0000071A"
},
{
"idx":32,
"id":"ED",
"value":"0x00000000",
"addr":"0x0000075C"
},
{
"idx":33,
"id":"EQ",
"value":"0x00000000",
"addr":"0x0000075E"
},
{
"idx":34,
"id":"SPEED_FDBK",
"value":"0x00000000",
"addr":"0x0000076E"
},
{
"idx":35,
"id":"THETA_EST",
"value":"0x00000000",
"addr":"0x00000774"
}
]
]
}

Can you re-send the link for the getting started video? Eric Chen posted it, tried to tag him, but there are quite a lot of Eric Chen's to choose from.

Link for it in here, now expired: https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1306649/mcf8329evm-mpet-not-working

0 Venkatadri Shantaram84961 1 month ago in reply to Neil

TI__Expert 4540 points

Hi Neil,

I will discuss with Eric to upload the video again.

I will reply to you for other questions by tomorrow.

Thanks and Best Regards,

Venkatadri S

0 Venkatadri Shantaram84961 1 month ago in reply to Venkatadri Shantaram84961

TI__Expert 4540 points

Hi Neil,

Sorry for late reply to this thread. I am looking into the thread now.

Few quick comments about the input.

We do not need to enter the R shunt in the GUI field. This version of GUI is initial version which require more updated .

Request to ignore configuring R shunt here until we release another version (expected soon)

Program GD CONFIG1 and GD CONFIG2 values for BASE CURRENT. In your JSON is 37.5A is used which is higher side.

If you are using 22mOhm shunt in the HW then use below table

CSA Gain of 10V/V and BASE CURRENT of 186 (0xBA)

Also, close loop accel and decel is very high in the closes loop. Let us reduce it until we see stable running.

Let us test MPET with changes to R shunt on the board and GD CONFIG registers.

Thanks and Best Regards,

Venkatadri S

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MCF8329EVM: MPET either does not run, gives a fault, or makes a high pitched squeal