Mini Cheetah Actuator Branch Superseded by: https://github.com/bgkatz/motorcontrol
Dependencies: mbed-dev-f303 FastPWM3
Superseded by: https://github.com/bgkatz/motorcontrol
FOC/foc.cpp
- Committer:
- benkatz
- Date:
- 2018-12-05
- Revision:
- 47:e1196a851f76
- Parent:
- 46:2d4b1dafcfe3
- Child:
- 48:74a40481740c
File content as of revision 47:e1196a851f76:
#include "foc.h" using namespace FastMath; void abc( float theta, float d, float q, float *a, float *b, float *c){ /// Inverse DQ0 Transform /// ///Phase current amplitude = lengh of dq vector/// ///i.e. iq = 1, id = 0, peak phase current of 1/// float cf = FastCos(theta); float sf = FastSin(theta); *a = cf*d - sf*q; // Faster Inverse DQ0 transform *b = (0.86602540378f*sf-.5f*cf)*d - (-0.86602540378f*cf-.5f*sf)*q; *c = (-0.86602540378f*sf-.5f*cf)*d - (0.86602540378f*cf-.5f*sf)*q; } void dq0(float theta, float a, float b, float c, float *d, float *q){ /// DQ0 Transform /// ///Phase current amplitude = lengh of dq vector/// ///i.e. iq = 1, id = 0, peak phase current of 1/// float cf = FastCos(theta); float sf = FastSin(theta); *d = 0.6666667f*(cf*a + (0.86602540378f*sf-.5f*cf)*b + (-0.86602540378f*sf-.5f*cf)*c); ///Faster DQ0 Transform *q = 0.6666667f*(-sf*a - (-0.86602540378f*cf-.5f*sf)*b - (0.86602540378f*cf-.5f*sf)*c); } void svm(float v_bus, float u, float v, float w, float *dtc_u, float *dtc_v, float *dtc_w){ /// Space Vector Modulation /// /// u,v,w amplitude = v_bus for full modulation depth /// float v_offset = (fminf3(u, v, w) + fmaxf3(u, v, w))/2.0f; *dtc_u = fminf(fmaxf(((u -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX); *dtc_v = fminf(fmaxf(((v -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX); *dtc_w = fminf(fmaxf(((w -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX); /* sinusoidal pwm *dtc_u = fminf(fmaxf((u/v_bus + .5f), DTC_MIN), DTC_MAX); *dtc_v = fminf(fmaxf((v/v_bus + .5f), DTC_MIN), DTC_MAX); *dtc_w = fminf(fmaxf((w/v_bus + .5f), DTC_MIN), DTC_MAX); */ } void zero_current(int *offset_1, int *offset_2){ // Measure zero-offset of the current sensors int adc1_offset = 0; int adc2_offset = 0; int n = 1024; for (int i = 0; i<n; i++){ // Average n samples of the ADC TIM1->CCR3 = (PWM_ARR>>1)*(1.0f); // Write duty cycles TIM1->CCR2 = (PWM_ARR>>1)*(1.0f); TIM1->CCR1 = (PWM_ARR>>1)*(1.0f); ADC1->CR2 |= 0x40000000; // Begin sample and conversion wait(.001); adc2_offset += ADC2->DR; adc1_offset += ADC1->DR; } *offset_1 = adc1_offset/n; *offset_2 = adc2_offset/n; } void init_controller_params(ControllerStruct *controller){ controller->ki_d = KI_D; controller->ki_q = KI_Q; controller->k_d = K_SCALE*I_BW; controller->k_q = K_SCALE*I_BW; controller->alpha = 1.0f - 1.0f/(1.0f - DT*I_BW*2.0f*PI); } void reset_foc(ControllerStruct *controller){ TIM1->CCR3 = (PWM_ARR>>1)*(0.5f); TIM1->CCR1 = (PWM_ARR>>1)*(0.5f); TIM1->CCR2 = (PWM_ARR>>1)*(0.5f); controller->i_d_ref = 0; controller->i_q_ref = 0; controller->i_d = 0; controller->i_q = 0; controller->i_q_filt = 0; controller->q_int = 0; controller->d_int = 0; controller->v_q = 0; controller->v_d = 0; } void limit_current_ref (ControllerStruct *controller){ float i_q_max_limit = (0.5774f*controller->v_bus - controller->dtheta_elec*WB)/R_PHASE; float i_q_min_limit = (-0.5774f*controller->v_bus - controller->dtheta_elec*WB)/R_PHASE; controller->i_q_ref = fmaxf(fminf(i_q_max_limit, controller->i_q_ref), i_q_min_limit); } void commutate(ControllerStruct *controller, GPIOStruct *gpio, float theta){ /// Commutation Loop /// controller->loop_count ++; if(PHASE_ORDER){ // Check current sensor ordering controller->i_b = I_SCALE*(float)(controller->adc2_raw - controller->adc2_offset); // Calculate phase currents from ADC readings controller->i_c = I_SCALE*(float)(controller->adc1_raw - controller->adc1_offset); } else{ controller->i_b = I_SCALE*(float)(controller->adc1_raw - controller->adc1_offset); controller->i_c = I_SCALE*(float)(controller->adc2_raw - controller->adc2_offset); } controller->i_a = -controller->i_b - controller->i_c; float s = FastSin(theta); float c = FastCos(theta); dq0(controller->theta_elec, controller->i_a, controller->i_b, controller->i_c, &controller->i_d, &controller->i_q); //dq0 transform on currents //controller->i_d = 0.6666667f*(c*controller->i_a + (0.86602540378f*s-.5f*c)*controller->i_b + (-0.86602540378f*s-.5f*c)*controller->i_c); ///Faster DQ0 Transform //controller->i_q = 0.6666667f*(-s*controller->i_a - (-0.86602540378f*c-.5f*s)*controller->i_b - (0.86602540378f*c-.5f*s)*controller->i_c); controller->i_q_filt = 0.95f*controller->i_q_filt + 0.05f*controller->i_q; controller->i_d_filt = 0.95f*controller->i_d_filt + 0.05f*controller->i_d; // Filter the current references to the desired closed-loopbandwidth // Allows calculation of desired di/dt for inductance, etc controller->did_dt = controller->i_d_ref_filt; controller->diq_dt = controller->i_q_ref_filt; controller->i_d_ref_filt = (1.0f-controller->alpha)*controller->i_d_ref_filt + controller->alpha*controller->i_d_ref; controller->i_q_ref_filt = (1.0f-controller->alpha)*controller->i_q_ref_filt + controller->alpha*controller->i_q_ref; controller->did_dt = (controller->i_d_ref_filt - controller->did_dt)/DT; controller->diq_dt = (controller->i_q_ref_filt - controller->diq_dt)/DT; /// Field Weakening /// /* controller->fw_int += .001*(0.5f*OVERMODULATION*controller->v_bus - controller->v_ref); controller->fw_int = fmaxf(fminf(controller->fw_int, 0.0f), -I_MAX_FW); controller->i_d_ref = controller->fw_int; float i_cmd_mag_sq = controller->i_d_ref*controller->i_d_ref + controller->i_q_ref*controller->i_q_ref; limit_norm(&controller->i_d_ref, &controller->i_q_ref, I_MAX); */ /// PI Controller /// float i_d_error = controller->i_d_ref - controller->i_d; float i_q_error = controller->i_q_ref - controller->i_q;// + cogging_current; // Calculate feed-forward voltages // float v_d_ff = 2.0f*(1.0f*controller->i_d_ref*R_PHASE - controller->dtheta_elec*L_Q*controller->i_q); //feed-forward voltages float v_q_ff = 2.0f*(1.0f*controller->i_q_ref*R_PHASE + controller->dtheta_elec*(L_D*controller->i_d + 1.0f*WB)); // Integrate Error // controller->d_int += controller->k_d*controller->ki_d*i_d_error; controller->q_int += controller->k_q*controller->ki_q*i_q_error; controller->d_int = fmaxf(fminf(controller->d_int, OVERMODULATION*controller->v_bus), - OVERMODULATION*controller->v_bus); controller->q_int = fmaxf(fminf(controller->q_int, OVERMODULATION*controller->v_bus), - OVERMODULATION*controller->v_bus); //limit_norm(&controller->d_int, &controller->q_int, OVERMODULATION*controller->v_bus); controller->v_d = controller->k_d*i_d_error + controller->d_int ;//+ v_d_ff; controller->v_q = controller->k_q*i_q_error + controller->q_int ;//+ v_q_ff; controller->v_ref = sqrt(controller->v_d*controller->v_d + controller->v_q*controller->v_q); limit_norm(&controller->v_d, &controller->v_q, OVERMODULATION*controller->v_bus); // Normalize voltage vector to lie within curcle of radius v_bus abc(controller->theta_elec + 0.0f*DT*controller->dtheta_elec, controller->v_d, controller->v_q, &controller->v_u, &controller->v_v, &controller->v_w); //inverse dq0 transform on voltages svm(controller->v_bus, controller->v_u, controller->v_v, controller->v_w, &controller->dtc_u, &controller->dtc_v, &controller->dtc_w); //space vector modulation if(PHASE_ORDER){ // Check which phase order to use, TIM1->CCR3 = (PWM_ARR)*(1.0f-controller->dtc_u); // Write duty cycles TIM1->CCR2 = (PWM_ARR)*(1.0f-controller->dtc_v); TIM1->CCR1 = (PWM_ARR)*(1.0f-controller->dtc_w); } else{ TIM1->CCR3 = (PWM_ARR)*(1.0f-controller->dtc_u); TIM1->CCR1 = (PWM_ARR)*(1.0f-controller->dtc_v); TIM1->CCR2 = (PWM_ARR)*(1.0f-controller->dtc_w); } controller->theta_elec = theta; //For some reason putting this at the front breaks thins } void torque_control(ControllerStruct *controller){ float torque_ref = controller->kp*(controller->p_des - controller->theta_mech) + controller->t_ff + controller->kd*(controller->v_des - controller->dtheta_mech); //float torque_ref = -.1*(controller->p_des - controller->theta_mech); controller->i_q_ref = torque_ref/KT_OUT; controller->i_d_ref = 0.0f; }