Rough acceleration - BLDC & FOC

Couldn't find a file upload option so i've copied and pasted the xml configuration below.

Link for the video is here - https://youtu.be/Y9JMlKcvBCs

You'll see in the video both sides seem to operate abnormally (to me at least). 

Bit hard to film the acceleration when on the board but will try.

I'm sure i've done something somewhere, but being my first dealings with the VESC tool, i thought i'd see if anyone could give some insight.



Thanks again.

<MCConfiguration>

<pwm_mode>1</pwm_mode>

<comm_mode>0</comm_mode>

<motor_type>0</motor_type>

<sensor_mode>2</sensor_mode>

<l_current_max>35</l_current_max>

<l_current_min>-25</l_current_min>

<l_in_current_max>99</l_in_current_max>

<l_in_current_min>-40</l_in_current_min>

<l_abs_current_max>150</l_abs_current_max>

<l_min_erpm>-100000</l_min_erpm>

<l_max_erpm>100000</l_max_erpm>

<l_erpm_start>0.8</l_erpm_start>

<l_max_erpm_fbrake>300</l_max_erpm_fbrake>

<l_max_erpm_fbrake_cc>1500</l_max_erpm_fbrake_cc>

<l_min_vin>8</l_min_vin>

<l_max_vin>57</l_max_vin>

<l_battery_cut_start>40.8</l_battery_cut_start>

<l_battery_cut_end>36</l_battery_cut_end>

<l_slow_abs_current>1</l_slow_abs_current>

<l_temp_fet_start>85</l_temp_fet_start>

<l_temp_fet_end>100</l_temp_fet_end>

<l_temp_motor_start>85</l_temp_motor_start>

<l_temp_motor_end>100</l_temp_motor_end>

<l_temp_accel_dec>0.15</l_temp_accel_dec>

<l_min_duty>0.02</l_min_duty>

<l_max_duty>0.96</l_max_duty>

<l_watt_max>1.5e+06</l_watt_max>

<l_watt_min>-1.5e+06</l_watt_min>

<l_current_max_scale>1</l_current_max_scale>

<l_current_min_scale>1</l_current_min_scale>

<sl_min_erpm>150</sl_min_erpm>

<sl_min_erpm_cycle_int_limit>2000</sl_min_erpm_cycle_int_limit>

<sl_max_fullbreak_current_dir_change>10</sl_max_fullbreak_current_dir_change>

<sl_cycle_int_limit>180.5</sl_cycle_int_limit>

<sl_phase_advance_at_br>0.8</sl_phase_advance_at_br>

<sl_cycle_int_rpm_br>80000</sl_cycle_int_rpm_br>

<sl_bemf_coupling_k>1321.18</sl_bemf_coupling_k>

<hall_table__0>6</hall_table__0>

<hall_table__1>1</hall_table__1>

<hall_table__2>5</hall_table__2>

<hall_table__3>6</hall_table__3>

<hall_table__4>3</hall_table__4>

<hall_table__5>2</hall_table__5>

<hall_table__6>4</hall_table__6>

<hall_table__7>6</hall_table__7>

<hall_sl_erpm>2000</hall_sl_erpm>

<foc_current_kp>0.0189</foc_current_kp>

<foc_current_ki>11.47</foc_current_ki>

<foc_f_sw>30000</foc_f_sw>

<foc_dt_us>0.12</foc_dt_us>

<foc_encoder_inverted>0</foc_encoder_inverted>

<foc_encoder_offset>180</foc_encoder_offset>

<foc_encoder_ratio>7</foc_encoder_ratio>

<foc_encoder_sin_gain>1</foc_encoder_sin_gain>

<foc_encoder_cos_gain>1</foc_encoder_cos_gain>

<foc_encoder_sin_offset>1.65</foc_encoder_sin_offset>

<foc_encoder_cos_offset>1.65</foc_encoder_cos_offset>

<foc_encoder_sincos_filter_constant>0.5</foc_encoder_sincos_filter_constant>

<foc_sensor_mode>2</foc_sensor_mode>

<foc_pll_kp>2000</foc_pll_kp>

<foc_pll_ki>30000</foc_pll_ki>

<foc_motor_l>7.542e-05</foc_motor_l>

<foc_motor_r>0.0459</foc_motor_r>

<foc_motor_flux_linkage>0.006489</foc_motor_flux_linkage>

<foc_observer_gain>5.17e+06</foc_observer_gain>

<foc_observer_gain_slow>0.3</foc_observer_gain_slow>

<foc_duty_dowmramp_kp>10</foc_duty_dowmramp_kp>

<foc_duty_dowmramp_ki>200</foc_duty_dowmramp_ki>

<foc_openloop_rpm>700</foc_openloop_rpm>

<foc_sl_openloop_hyst>0.1</foc_sl_openloop_hyst>

<foc_sl_openloop_time>0.1</foc_sl_openloop_time>

<foc_sl_d_current_duty>0</foc_sl_d_current_duty>

<foc_sl_d_current_factor>0</foc_sl_d_current_factor>

<foc_hall_table__0>255</foc_hall_table__0>

<foc_hall_table__1>103</foc_hall_table__1>

<foc_hall_table__2>169</foc_hall_table__2>

<foc_hall_table__3>135</foc_hall_table__3>

<foc_hall_table__4>36</foc_hall_table__4>

<foc_hall_table__5>70</foc_hall_table__5>

<foc_hall_table__6>2</foc_hall_table__6>

<foc_hall_table__7>255</foc_hall_table__7>

<foc_sl_erpm>2000</foc_sl_erpm>

<foc_sample_v0_v7>0</foc_sample_v0_v7>

<foc_sample_high_current>0</foc_sample_high_current>

<foc_sat_comp>0.1</foc_sat_comp>

<foc_temp_comp>0</foc_temp_comp>

<foc_temp_comp_base_temp>25</foc_temp_comp_base_temp>

<foc_current_filter_const>0.1</foc_current_filter_const>

<foc_cc_decoupling>2</foc_cc_decoupling>

<foc_observer_type>0</foc_observer_type>

<foc_hfi_voltage_start>20</foc_hfi_voltage_start>

<foc_hfi_voltage_run>4</foc_hfi_voltage_run>

<foc_hfi_voltage_max>10</foc_hfi_voltage_max>

<foc_sl_erpm_hfi>2000</foc_sl_erpm_hfi>

<foc_hfi_start_samples>65</foc_hfi_start_samples>

<foc_hfi_obs_ovr_sec>0.001</foc_hfi_obs_ovr_sec>

<foc_hfi_samples>1</foc_hfi_samples>

<gpd_buffer_notify_left>200</gpd_buffer_notify_left>

<gpd_buffer_interpol>0</gpd_buffer_interpol>

<gpd_current_filter_const>0.1</gpd_current_filter_const>

<gpd_current_kp>0.03</gpd_current_kp>

<gpd_current_ki>50</gpd_current_ki>

<s_pid_kp>0.004</s_pid_kp>

<s_pid_ki>0.004</s_pid_ki>

<s_pid_kd>0.001</s_pid_kd>

<s_pid_kd_filter>0.2</s_pid_kd_filter>

<s_pid_min_erpm>900</s_pid_min_erpm>

<s_pid_allow_braking>1</s_pid_allow_braking>

<p_pid_kp>0.03</p_pid_kp>

<p_pid_ki>0</p_pid_ki>

<p_pid_kd>0.0004</p_pid_kd>

<p_pid_kd_filter>0.2</p_pid_kd_filter>

<p_pid_ang_div>1</p_pid_ang_div>

<cc_startup_boost_duty>0.1</cc_startup_boost_duty>

<cc_min_current>0.05</cc_min_current>

<cc_gain>0.2</cc_gain>

<cc_ramp_step_max>0.04</cc_ramp_step_max>

<m_fault_stop_time_ms>500</m_fault_stop_time_ms>

<m_duty_ramp_step>0.04</m_duty_ramp_step>

<m_current_backoff_gain>0.5</m_current_backoff_gain>

<m_encoder_counts>8192</m_encoder_counts>

<m_sensor_port_mode>0</m_sensor_port_mode>

<m_invert_direction>0</m_invert_direction>

<m_drv8301_oc_mode>0</m_drv8301_oc_mode>

<m_drv8301_oc_adj>16</m_drv8301_oc_adj>

<m_bldc_f_sw_min>3000</m_bldc_f_sw_min>

<m_bldc_f_sw_max>35000</m_bldc_f_sw_max>

<m_dc_f_sw>25000</m_dc_f_sw>

<m_ntc_motor_beta>3380</m_ntc_motor_beta>

<m_out_aux_mode>0</m_out_aux_mode>

<m_motor_temp_sens_type>0</m_motor_temp_sens_type>

<m_ptc_motor_coeff>0.61</m_ptc_motor_coeff>

<si_motor_poles>14</si_motor_poles>

<si_gear_ratio>4.4</si_gear_ratio>

<si_wheel_diameter>0.175</si_wheel_diameter>

<si_battery_type>0</si_battery_type>

<si_battery_cells>12</si_battery_cells>

<si_battery_ah>14</si_battery_ah>

<motor_brand>Unnamed</motor_brand>

<motor_model>Not Specified</motor_model>

<motor_weight>0</motor_weight>

<motor_poles>14</motor_poles>

<motor_sensor_type>0</motor_sensor_type>

<motor_description>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN" "http://www.w3.org/TR/REC-html40/strict.dtd"> <html><head><meta name="qrichtext" content="1" /><style type="text/css"> p, li { white-space: pre-wrap; } </style></head><body style=" font-family:'DejaVu Sans'; font-size:11pt; font-weight:400; font-style:normal;"> <p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">A motor description can be edited here.</p></body></html>

</motor_description>

<motor_loss_torque>0.03</motor_loss_torque>

<motor_quality_bearings>0</motor_quality_bearings>

<motor_quality_magnets>0</motor_quality_magnets>

<motor_quality_construction>0</motor_quality_construction>

<motor_quality_description>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN" "http://www.w3.org/TR/REC-html40/strict.dtd"> <html><head><meta name="qrichtext" content="1" /><style type="text/css"> p, li { white-space: pre-wrap; } </style></head><body style=" font-family:'DejaVu Sans'; font-size:11pt; font-weight:400; font-style:normal;"> <p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">Some comments about the motor quality. Images can be added as well.</p></body></html>

</motor_quality_description>

</MCConfiguration>

Pretty sure was 'current' mode. 

I ended up returning the app configuration back to original and starting again.

I tried FOC again, but it still doesn't operate correctly. Start-up is far better than when in BLDC, however when it reaches the sensored ERPM limit, the motors start cogging really badly. 

If you set the sensored ERPM to 70,000 (10,000rpm real world), they will spin all the way up, but with excessive noise and heat building, even when operating them in the air. Almost like the "timing" is out and applying current at the wrong intervals, causing increased resistance and subsequently heat.

I need to go back to it today. Going to try different motors on the chance these have something odd going on with them.

Update-

I've gone back to setting it up in FOC. With the initial set up parameters it still wouldn't function correctly above the sensorless ERPM limit. 

I went through and changed the coupling to cross and BEMF and set High Current Sampling and Sample in V0 & V7 both to True.

This resulted in both motors seemingly working properly, however, with the motor from the slave unit triggering ABS Over Current initially on full acceleration free-spinning, then coming good.

Found that manually carrying out the FOC parameter detection was returning varying results every time and i think the increasing inductance and resistance readings were attributing to this fault.

From the first detection coming back with around 42 & 55 inductance, to the final runs coming back with anything up 250 and 300?

I've ended up setting the resistance, inductance and flux linkage to be in-line with what they were detected as in the first place.

These are:

R: 52.60 & 66.3

L: 42.73 & 54.55

Flux: 6.45 & 6.25

Now the motors are seemingly operating as they should. 

Problem currently is getting the VESC to maintain CAN communication to set motor direction (keeps dropping out).

my next question-

while the board seems to be operating relatively smoothly and has pick up once rolling, it's lacking the sudden acceleration i was hoping for with the 12s battery. Currently, it feels less than the GTR did stock.

Positive and negative ramping in PPM settings is at 0.1.



Running 35a/motor. Short of bumping up current, is there a way to increase acceleration response on FOC similar to how the BLDC operation utilises current control gain?