File content as of revision 52:15a8de8af562:

#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))*0.5f;
    
    *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 linearize_dtc(float *dtc){
    /// linearizes the output of the inverter, which is not linear for small duty cycles ///
    float sgn = 1.0f-(2.0f*(dtc<0));
    if(abs(*dtc) >= .01f){
        *dtc = *dtc*.986f+.014f*sgn;
        }
    else{
        *dtc = 2.5f*(*dtc);
        }
    
    }
    
    
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 reset_observer(ObserverStruct *observer){
    observer->temperature = 25.0f;
    observer->resistance = .1f;
    }
    
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, ObserverStruct *observer, GPIOStruct *gpio, float theta){
        
        /// Update observer estimates ///
        // Resistance observer //
        // Temperature Observer //
        float t_rise = (float)observer->temperature - 25.0f;
        float q_th_in = (1.0f + .00393f*t_rise)*(controller->i_d*controller->i_d*R_PHASE*SQRT3 + controller->i_q*controller->i_q*R_PHASE*SQRT3);
        float q_th_out = t_rise*R_TH;
        observer->temperature += INV_M_TH*DT*(q_th_in-q_th_out);
        
        observer->resistance = (controller->v_q - SQRT3*controller->dtheta_elec*(WB))/controller->i_q;
        //observer->resistance = controller->v_q/controller->i_q;
        if(isnan(observer->resistance)){observer->resistance = R_PHASE;}
        observer->temperature2 = (double)(25.0f + ((observer->resistance*6.0606f)-1.0f)*275.5f);
        double e = observer->temperature - observer->temperature2;
        observer->temperature -= .001*e;
        //printf("%.3f\n\r", e);
        

       /// 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-loop bandwidth
        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;

       
       /// Field Weakening ///
       
       controller->fw_int += .001f*(0.5f*OVERMODULATION*controller->v_bus - controller->v_ref);
       controller->fw_int = fmaxf(fminf(controller->fw_int, 0.0f), -I_FW_MAX);
       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 = SQRT3*(1.0f*controller->i_d_ref*R_PHASE  - controller->dtheta_elec*L_Q*controller->i_q);   //feed-forward voltages
       float v_q_ff =  SQRT3*(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
       float dtc_d = controller->v_d/controller->v_bus;
       float dtc_q = controller->v_q/controller->v_bus;
       linearize_dtc(&dtc_d);
       linearize_dtc(&dtc_q);
       controller->v_d = dtc_d*controller->v_bus;
       controller->v_q = dtc_q*controller->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;                                          
       
    }
    
    
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;
    }