Question for stall error at right before HD overvoltage detection

[young-kyunpark]

Hi,

My motor stall as the attached figure.

I'm using S12ZVML128 on my own PCB.

Here is my test settings.

0. Motor info

   6 pole pairs

   max rpm : 4000

   100W

1. GDU setting

   GDUE_GCPE = 1; /* charge pump enable*/
   GDUE_GCSE0 = 1; /* enable Current Sense Amplifier 0*/
   GDUF = 0xff; /* Flag Register - clear all error flags*/  
   GDUE_GBOE = 1; /* Boost converter enable*/

   GDUCLK2_GCPCD = 2;  /* Fbus / 32*/
   GDUCTR = 0x13; /* blanking time and overvoltage detection thershold */

   GDUDSLVL = 0x77; /* desatuartion level*/

   GDUE_GFDE = 1;  /* enable FET pre-driver*/  
   GDUDSE = 0x77;   /* Clear Desaturation Error Flags*/

2. PMF setting

  PMFCFG0_EDGEA = 1; /*PWM0 and PWM1 are edge-aligned PWMs*/
  PMFCFG0_EDGEB = 1;    /*PWM2 and PWM3 are edge-aligned PWMs */
  PMFCFG0_EDGEC = 1; /*PWM4 and PWM5 are edge-aligned PWMs*/

  PMFCFG2_REV0 = 1;    /* 01 PWM generator A generates reload event.*/
  PMFCFG2_REV1 = 0;  /* 01 PWM generator A generates reload event.*/

  PMFOUTB = 0x2A;  /*  Low MOSFETs ON while SW control (Unipolar PWM)*/

  PMFCFG3_VLMODE = 0x01; /* Writing to value register zero also writes to value registers one to five*/

  PMFFQCA = 0;              /* Reload every PWM, Half-cycle disabled, fcore / 1*/

  PMFMODA = 2000; /* Switching Frequency : 12.5KHz*/
  PMFDTMA = 13;

  PMFCFG2 |= 0x3f;   /* mask all PWM outputs*/
  PMFOUTC_OUTCTL = 0x3f;  /* all outputs in Software mode*/
  PMFENCA_LDOKA = 1;   /* apply PMF Modulo value*/

  PMFENCA_RSTRTA = 1;         /* 1 = PWM restart at commutation event*/

  PMFENCA_PWMENA = 1;

  PMFCFG1_ENCE = 1;     /* Commutation event input enabled and PMFOUTC, PMFOUTB and MSKn buffered*/

  PMFENCA_GLDOKA = 1;         /* 0 = Local LDOKA controls buffered registers / 1 = external Load OK controls buffered registers*/

3. Power Supply setting
   Trapezoid voltage input from 13V to 22V during 5sec.

observed motor stall condition ;

- Motor speed : 1500RPM ~ 3000RPM (didn't test over 3000RPM)

- Input voltage : over 18V (I know the norminal voltage range 6~18V)

I want to know why motor stall before GHHDF set.

What should I check?

[Martin35804]

Hi,

I would recommend to go through the examples that are available for the

MTRCKTSBNZVM128: 3-phase Sensorless BLDC Development Kit with S12 MagniV MC9S12ZVML128 MCU

MTRCKTSBNZVM128_SW: Complete motor control application software package for MTRCKTSBNZVM128

as well as the corresponding application notes AN4704 and AN4718

This demo uses BLDC motor that can be used for sensorless or Hall sensor connection.

Parameters of the motor are following:

DC24V

90W

9350 rpm

Below are some settings calculation that might help regarding to your setup.

Check for following input configuration:

Motor Parameters
No. of Pol pairs	6	[-]
Nominal speed	2000	[rpm]
Nominal current	25	[A]
Resistance	0,286	[Ohm]
Back-EMF constant	0,005206693	[V.sec.rad-1]
Min required speed	8,0%	[%] of nominal speed
Max required speed	200,0%	[%] of nominal speed
Max current	50,0%	[%] of nominal current
Start up parameters
Alignment time	4000	[ms]
Alignment current	20,0%	[%] of nominal current
No of start up comutataions	12	-
first start period	80	[ms]
Board Scales
Max Meas Current	40	[A]
DC Link Voltage	13	[V]
Timer
Timer	1,28	us

You should have following following outputs:

Alignment parameters
ALIGNMENT_TIME	4000	int
ALIGN_CURRENT_SCALED	FRAC16(0.125)	frac
Open Loop Start up parameters
START_CMT_CNT	12	-
START_FIRST_PERIOD	62500	int
REQUIRED_RUN_SPEED	FRAC16(0.000)	frac
START_CMT_ACCELERATION	FRAC16(000.001)	frac
Run parameters
MIN_SPEED	FRAC16(0.000)	frac
MAX_SPEED	FRAC16(0.001)	frac
SPEED_STEP	FRAC16(0.000)	frac
SPEED_CALC_NUMERATOR	63941406	int
DC_BUS_CURRENT_LIMIT	FRAC16(0.313)	frac
RUN_PI_LOWER_LIMIT	FRAC16(0.000)
Stall checker parameters
STALLCHECK_MIN_CMT_PERIOD	362	int

and following calculated values:

Nominal speed	33,33333333	Hz
Nominal Electrical Speed	200	Hz
Min speed	160	rpm
Max speed	4000	rpm
Max speed	66,66666667	Hz
Max Electrical Speed	400	Hz
Time between two commutations @ max speed	0,000416667	s
Time required for one electrical revolution @max speed	0,0025	s
Count between two commutataions @ max speed	325,5208333	int
Count required for one electrical revolution @max speed	1953,125	int
Voltage to achieve Min Speed	0,523433875	V
last start period	10,41666667	[ms]

Will post this calc. in near future at this community.

You may also refer to following thread:

S12ZVML-MINIBRD and BMW electronic pump

especially this part for the start-up section:

When the star-up parameters are wrong the the motor is during the startup vibrating and when it is switched to run mode it depends on which side has the motor vibrated at last (whether it has accelerated to much or decelerated during the last commutation).

That's why it is crucial for this application of the open loop start motor to set up properly, and sometimes via experimenting, following key parameters:

• Duration of first commutation
• Number of commutations
• Acceleration (ration how much is the each following commutation shorter)
• Alignment current