Hi,
i'm having some issues with my custom board. Anyhow the just a bit torque is generated and a weird noise occurs. It must have to do with the current controller or with the Bemf' measurement. The motor is loudly and doesnt behave smooth. When the speed is above 50% of the rated speed the nose dissapeares and control works better. I have a few ideas what it could be. But first i would like to check my user.h settings. I am not sure if i did the settings correctly.
Thanks in advance for checking :)
at first my motor:
#define USER_MOTOR_TYPE MOTOR_Type_Pm // Motor_Type_Pm (All Synchronous: BLDC, PMSM, SMPM, IPM) or Motor_Type_Induction (Asynchronous ACI)
#define USER_MOTOR_NUM_POLE_PAIRS (15) //eventuell 17 // PAIRS, not total poles. Used to calculate user RPM from rotor Hz only
#define USER_MOTOR_Rr (NULL) // Induction motors only, else NULL
#define USER_MOTOR_Rs (0.0781600699) // Identified phase to neutral resistance in a Y equivalent circuit (Ohms, float)
#define USER_MOTOR_Ls_d (0.000108673121) // For PM, Identified average stator inductance (Henry, float)
#define USER_MOTOR_Ls_q (0.000108673121) // For PM, Identified average stator inductance (Henry, float)
#define USER_MOTOR_RATED_FLUX (0.0755883753)
#define USER_IQ_FULL_SCALE_FREQ_Hz (800.0) I calculated following: 770RPM max speed= 12.8U/s 12.8U/s*15polepairs =200Hz. I thougt setting it higher would be ok if i will use a motor with a higher speed with this controller
#define USER_ADC_FULL_SCALE_VOLTAGE_V (52.899) My resistors are 75kOhm and 4.99kOhm My nominal voltage is 22 to 25.2V but we designed it for 50V fpr unexpected high Bemf's or for the use with more supply voltage.
#define USER_IQ_FULL_SCALE_VOLTAGE_V (52) Is this correct? Once i read that it should be a bit above the nominal voltage. I thought this value just sclaes the pu-value? I don't want to get overrun when FW is ON
#define USER_ADC_FULL_SCALE_CURRENT_A (110.0) 3mOhm resistor We desiggned it higher than our needs are. Actually the phase crurrent have an amplitude of about 30A
#define USER_IQ_FULL_SCALE_CURRENT_A (65.0)
#define USER_PWM_FREQ_kHz (60.0) How about his frequency? My motor is a 30 pole hub-motor. Inductance of 108mH It hink 10kHz should be enough for smooth nice sone wave? ALso Main isr should be finished executing before next interrupt
#define USER_NUM_PWM_TICKS_PER_ISR_TICK (3)
#define USER_NUM_ISR_TICKS_PER_CTRL_TICK (1)
#define USER_NUM_CTRL_TICKS_PER_CURRENT_TICK (1)
I thougt a higher frequency would be more accurate in controlling. But could it be that this is much to high? because of losses i want to lower it. Is there any way to calculate which pwm frequency would be "good"?
#define USER_VOLTAGE_FILTER_POLE_Hz (340.168) // 364.682, value for boostxldrv8301_revB hardware
Calculated it from our hardware setting. Phase voltage dividers are 75kOhm and 4.99kOhm C is 0.1µF -> fg=340.168Hz
I read a lot of labs, forum posts and so on but it is still not everything clear to me.
Thanks i advance!
Sebastian
