Shao Rui / Brushless_Motor_12_3

123487

Dependencies:   mbed-dev-f303 FastPWM3

FOC/foc.cpp@55:14ac00a5f43d, 2019-11-19 (annotated)

Committer:
Rushu
Date:
Tue Nov 19 08:54:35 2019 +0000
Revision:
55:14ac00a5f43d
Parent:
51:6cd89bd6fcaa 
AS5147

Who changed what in which revision?

UserRevisionLine numberNew contents of line
benkatz 37:c0f352d6e8e3 1
benkatz 22:60276ba87ac6 2 #include "foc.h"
benkatz 26:2b865c00d7e9 3 using namespace FastMath;
benkatz 22:60276ba87ac6 4
benkatz 22:60276ba87ac6 5
benkatz 22:60276ba87ac6 6 void abc( float theta, float d, float q, float *a, float *b, float *c){
benkatz 25:f5741040c4bb 7 /// Inverse DQ0 Transform ///
benkatz 22:60276ba87ac6 8 ///Phase current amplitude = lengh of dq vector///
benkatz 22:60276ba87ac6 9 ///i.e. iq = 1, id = 0, peak phase current of 1///
benkatz 37:c0f352d6e8e3 10 float cf = FastCos(theta);
benkatz 37:c0f352d6e8e3 11 float sf = FastSin(theta);
benkatz 37:c0f352d6e8e3 12
benkatz 37:c0f352d6e8e3 13 *a = cf*d - sf*q; // Faster Inverse DQ0 transform
benkatz 37:c0f352d6e8e3 14 *b = (0.86602540378f*sf-.5f*cf)*d - (-0.86602540378f*cf-.5f*sf)*q;
benkatz 37:c0f352d6e8e3 15 *c = (-0.86602540378f*sf-.5f*cf)*d - (0.86602540378f*cf-.5f*sf)*q;
benkatz 22:60276ba87ac6 16 }
benkatz 22:60276ba87ac6 17
benkatz 26:2b865c00d7e9 18
benkatz 22:60276ba87ac6 19 void dq0(float theta, float a, float b, float c, float *d, float *q){
benkatz 25:f5741040c4bb 20 /// DQ0 Transform ///
benkatz 22:60276ba87ac6 21 ///Phase current amplitude = lengh of dq vector///
benkatz 22:60276ba87ac6 22 ///i.e. iq = 1, id = 0, peak phase current of 1///
benkatz 22:60276ba87ac6 23
benkatz 37:c0f352d6e8e3 24 float cf = FastCos(theta);
benkatz 37:c0f352d6e8e3 25 float sf = FastSin(theta);
benkatz 26:2b865c00d7e9 26
benkatz 37:c0f352d6e8e3 27 *d = 0.6666667f*(cf*a + (0.86602540378f*sf-.5f*cf)*b + (-0.86602540378f*sf-.5f*cf)*c); ///Faster DQ0 Transform
benkatz 37:c0f352d6e8e3 28 *q = 0.6666667f*(-sf*a - (-0.86602540378f*cf-.5f*sf)*b - (0.86602540378f*cf-.5f*sf)*c);
benkatz 37:c0f352d6e8e3 29
benkatz 22:60276ba87ac6 30 }
benkatz 22:60276ba87ac6 31
benkatz 22:60276ba87ac6 32 void svm(float v_bus, float u, float v, float w, float *dtc_u, float *dtc_v, float *dtc_w){
benkatz 25:f5741040c4bb 33 /// Space Vector Modulation ///
benkatz 25:f5741040c4bb 34 /// u,v,w amplitude = v_bus for full modulation depth ///
benkatz 22:60276ba87ac6 35
benkatz 48:74a40481740c 36 float v_offset = (fminf3(u, v, w) + fmaxf3(u, v, w))*0.5f;
benkatz 47:e1196a851f76 37
benkatz 31:61eb6ae28215 38 *dtc_u = fminf(fmaxf(((u -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 31:61eb6ae28215 39 *dtc_v = fminf(fmaxf(((v -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 47:e1196a851f76 40 *dtc_w = fminf(fmaxf(((w -v_offset)/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 47:e1196a851f76 41
benkatz 47:e1196a851f76 42 /*
benkatz 47:e1196a851f76 43 sinusoidal pwm
benkatz 47:e1196a851f76 44 *dtc_u = fminf(fmaxf((u/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 47:e1196a851f76 45 *dtc_v = fminf(fmaxf((v/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 47:e1196a851f76 46 *dtc_w = fminf(fmaxf((w/v_bus + .5f), DTC_MIN), DTC_MAX);
benkatz 47:e1196a851f76 47 */
benkatz 47:e1196a851f76 48
benkatz 22:60276ba87ac6 49
benkatz 22:60276ba87ac6 50 }
benkatz 22:60276ba87ac6 51
benkatz 48:74a40481740c 52 void linearize_dtc(float *dtc){
benkatz 48:74a40481740c 53 /// linearizes the output of the inverter, which is not linear for small duty cycles ///
benkatz 48:74a40481740c 54 float sgn = 1.0f-(2.0f*(dtc<0));
benkatz 48:74a40481740c 55 if(abs(*dtc) >= .01f){
benkatz 48:74a40481740c 56 *dtc = *dtc*.986f+.014f*sgn;
benkatz 48:74a40481740c 57 }
benkatz 48:74a40481740c 58 else{
benkatz 48:74a40481740c 59 *dtc = 2.5f*(*dtc);
benkatz 48:74a40481740c 60 }
benkatz 48:74a40481740c 61
benkatz 48:74a40481740c 62 }
benkatz 48:74a40481740c 63
benkatz 48:74a40481740c 64
benkatz 25:f5741040c4bb 65 void zero_current(int *offset_1, int *offset_2){ // Measure zero-offset of the current sensors
benkatz 22:60276ba87ac6 66 int adc1_offset = 0;
benkatz 22:60276ba87ac6 67 int adc2_offset = 0;
benkatz 22:60276ba87ac6 68 int n = 1024;
benkatz 25:f5741040c4bb 69 for (int i = 0; i<n; i++){ // Average n samples of the ADC
benkatz 27:501fee691e0e 70 TIM1->CCR3 = (PWM_ARR>>1)*(1.0f); // Write duty cycles
benkatz 27:501fee691e0e 71 TIM1->CCR2 = (PWM_ARR>>1)*(1.0f);
benkatz 27:501fee691e0e 72 TIM1->CCR1 = (PWM_ARR>>1)*(1.0f);
benkatz 26:2b865c00d7e9 73 ADC1->CR2 |= 0x40000000; // Begin sample and conversion
benkatz 22:60276ba87ac6 74 wait(.001);
benkatz 22:60276ba87ac6 75 adc2_offset += ADC2->DR;
benkatz 22:60276ba87ac6 76 adc1_offset += ADC1->DR;
benkatz 22:60276ba87ac6 77 }
benkatz 22:60276ba87ac6 78 *offset_1 = adc1_offset/n;
benkatz 22:60276ba87ac6 79 *offset_2 = adc2_offset/n;
benkatz 22:60276ba87ac6 80 }
benkatz 45:26801179208e 81
benkatz 45:26801179208e 82 void init_controller_params(ControllerStruct *controller){
benkatz 45:26801179208e 83 controller->ki_d = KI_D;
benkatz 45:26801179208e 84 controller->ki_q = KI_Q;
benkatz 45:26801179208e 85 controller->k_d = K_SCALE*I_BW;
benkatz 45:26801179208e 86 controller->k_q = K_SCALE*I_BW;
benkatz 45:26801179208e 87 controller->alpha = 1.0f - 1.0f/(1.0f - DT*I_BW*2.0f*PI);
benkatz 45:26801179208e 88
benkatz 45:26801179208e 89 }
benkatz 22:60276ba87ac6 90
benkatz 22:60276ba87ac6 91 void reset_foc(ControllerStruct *controller){
benkatz 28:8c7e29f719c5 92 TIM1->CCR3 = (PWM_ARR>>1)*(0.5f);
benkatz 28:8c7e29f719c5 93 TIM1->CCR1 = (PWM_ARR>>1)*(0.5f);
benkatz 28:8c7e29f719c5 94 TIM1->CCR2 = (PWM_ARR>>1)*(0.5f);
benkatz 28:8c7e29f719c5 95 controller->i_d_ref = 0;
benkatz 28:8c7e29f719c5 96 controller->i_q_ref = 0;
benkatz 28:8c7e29f719c5 97 controller->i_d = 0;
benkatz 28:8c7e29f719c5 98 controller->i_q = 0;
benkatz 37:c0f352d6e8e3 99 controller->i_q_filt = 0;
benkatz 22:60276ba87ac6 100 controller->q_int = 0;
benkatz 22:60276ba87ac6 101 controller->d_int = 0;
benkatz 28:8c7e29f719c5 102 controller->v_q = 0;
benkatz 28:8c7e29f719c5 103 controller->v_d = 0;
benkatz 47:e1196a851f76 104
benkatz 22:60276ba87ac6 105 }
benkatz 45:26801179208e 106
benkatz 48:74a40481740c 107 void reset_observer(ObserverStruct *observer){
benkatz 48:74a40481740c 108 observer->temperature = 25.0f;
benkatz 48:74a40481740c 109 observer->resistance = .1f;
benkatz 48:74a40481740c 110 }
benkatz 48:74a40481740c 111
benkatz 45:26801179208e 112 void limit_current_ref (ControllerStruct *controller){
benkatz 45:26801179208e 113 float i_q_max_limit = (0.5774f*controller->v_bus - controller->dtheta_elec*WB)/R_PHASE;
benkatz 45:26801179208e 114 float i_q_min_limit = (-0.5774f*controller->v_bus - controller->dtheta_elec*WB)/R_PHASE;
benkatz 45:26801179208e 115 controller->i_q_ref = fmaxf(fminf(i_q_max_limit, controller->i_q_ref), i_q_min_limit);
benkatz 45:26801179208e 116 }
benkatz 22:60276ba87ac6 117
benkatz 22:60276ba87ac6 118
benkatz 48:74a40481740c 119 void commutate(ControllerStruct *controller, ObserverStruct *observer, GPIOStruct *gpio, float theta){
benkatz 48:74a40481740c 120
benkatz 48:74a40481740c 121 /// Update observer estimates ///
benkatz 48:74a40481740c 122 // Resistance observer //
benkatz 48:74a40481740c 123 // Temperature Observer //
benkatz 48:74a40481740c 124 float t_rise = (float)observer->temperature - 25.0f;
benkatz 49:83d83040ea51 125 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);
benkatz 48:74a40481740c 126 float q_th_out = t_rise*R_TH;
benkatz 48:74a40481740c 127 observer->temperature += INV_M_TH*DT*(q_th_in-q_th_out);
benkatz 48:74a40481740c 128
benkatz 49:83d83040ea51 129 observer->resistance = (controller->v_q - SQRT3*controller->dtheta_elec*(WB))/controller->i_q;
benkatz 49:83d83040ea51 130 //observer->resistance = controller->v_q/controller->i_q;
benkatz 48:74a40481740c 131 if(isnan(observer->resistance)){observer->resistance = R_PHASE;}
benkatz 48:74a40481740c 132 observer->temperature2 = (double)(25.0f + ((observer->resistance*6.0606f)-1.0f)*275.5f);
benkatz 48:74a40481740c 133 double e = observer->temperature - observer->temperature2;
benkatz 48:74a40481740c 134 observer->temperature -= .001*e;
benkatz 48:74a40481740c 135 //printf("%.3f\n\r", e);
Rushu 55:14ac00a5f43d 136 /*
Rushu 55:14ac00a5f43d 137 // Integrate the thermal model //
Rushu 55:14ac00a5f43d 138 delta_t = observer.temperature - T_AMBIENT;
Rushu 55:14ac00a5f43d 139 observer.qd_in = R_NOMINAL**(1.0f + .00393f*delta_t)*controller.i*controller.i;
Rushu 55:14ac00a5f43d 140 observer.qd_out = delta_t*R_TH;
Rushu 55:14ac00a5f43d 141 observer.temperature += DT*(observer.qd_in-observer.qd_out)/C_TH;
Rushu 55:14ac00a5f43d 142
Rushu 55:14ac00a5f43d 143 // Estimate Resistance //
Rushu 55:14ac00a5f43d 144 observer.resistance = (controller.v_q - controller.omega*(L_D*controller.i_d + WB))/(controller.i_q);
benkatz 48:74a40481740c 145
Rushu 55:14ac00a5f43d 146 // Estimate Temperature from temp-co //
Rushu 55:14ac00a5f43d 147 observer.t_measured = ((T_AMBIENT + ((observer.resistance/R_NOMINAL) - 1.0f)*254.5f));
Rushu 55:14ac00a5f43d 148
Rushu 55:14ac00a5f43d 149 // Update Observer with measured temperature //
Rushu 55:14ac00a5f43d 150 e = (float)observer.temperature - observer.temp_measured;
Rushu 55:14ac00a5f43d 151 //observer.temperature -= .0001f*e;
Rushu 55:14ac00a5f43d 152 // Calculate "trust" based on state //
Rushu 55:14ac00a5f43d 153 observer.trust = (1.0f - .004f*fminf(abs(controller.dtheta_elec), 250.0f)) * (.01f*(fminf(controller.current^2, 100.0f)));
Rushu 55:14ac00a5f43d 154
Rushu 55:14ac00a5f43d 155 // Scale observer gain by "trust" //
Rushu 55:14ac00a5f43d 156 // .0001 is the default observer gain //
Rushu 55:14ac00a5f43d 157 observer.temperature -= observer.trust*.0001f*e;
Rushu 55:14ac00a5f43d 158
Rushu 55:14ac00a5f43d 159
Rushu 55:14ac00a5f43d 160 */
benkatz 25:f5741040c4bb 161 /// Commutation Loop ///
benkatz 25:f5741040c4bb 162 controller->loop_count ++;
benkatz 25:f5741040c4bb 163 if(PHASE_ORDER){ // Check current sensor ordering
benkatz 25:f5741040c4bb 164 controller->i_b = I_SCALE*(float)(controller->adc2_raw - controller->adc2_offset); // Calculate phase currents from ADC readings
benkatz 22:60276ba87ac6 165 controller->i_c = I_SCALE*(float)(controller->adc1_raw - controller->adc1_offset);
benkatz 22:60276ba87ac6 166 }
benkatz 22:60276ba87ac6 167 else{
benkatz 25:f5741040c4bb 168 controller->i_b = I_SCALE*(float)(controller->adc1_raw - controller->adc1_offset);
benkatz 22:60276ba87ac6 169 controller->i_c = I_SCALE*(float)(controller->adc2_raw - controller->adc2_offset);
benkatz 22:60276ba87ac6 170 }
benkatz 26:2b865c00d7e9 171 controller->i_a = -controller->i_b - controller->i_c;
benkatz 22:60276ba87ac6 172
benkatz 26:2b865c00d7e9 173 float s = FastSin(theta);
benkatz 26:2b865c00d7e9 174 float c = FastCos(theta);
benkatz 44:8040fa2fcb0d 175 dq0(controller->theta_elec, controller->i_a, controller->i_b, controller->i_c, &controller->i_d, &controller->i_q); //dq0 transform on currents
benkatz 44:8040fa2fcb0d 176 //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
benkatz 44:8040fa2fcb0d 177 //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);
benkatz 37:c0f352d6e8e3 178
benkatz 37:c0f352d6e8e3 179 controller->i_q_filt = 0.95f*controller->i_q_filt + 0.05f*controller->i_q;
benkatz 47:e1196a851f76 180 controller->i_d_filt = 0.95f*controller->i_d_filt + 0.05f*controller->i_d;
benkatz 37:c0f352d6e8e3 181
benkatz 45:26801179208e 182
benkatz 49:83d83040ea51 183 // Filter the current references to the desired closed-loop bandwidth
benkatz 45:26801179208e 184 controller->i_d_ref_filt = (1.0f-controller->alpha)*controller->i_d_ref_filt + controller->alpha*controller->i_d_ref;
benkatz 45:26801179208e 185 controller->i_q_ref_filt = (1.0f-controller->alpha)*controller->i_q_ref_filt + controller->alpha*controller->i_q_ref;
benkatz 48:74a40481740c 186
benkatz 48:74a40481740c 187
benkatz 48:74a40481740c 188 /// Field Weakening ///
benkatz 48:74a40481740c 189
benkatz 48:74a40481740c 190 controller->fw_int += .001f*(0.5f*OVERMODULATION*controller->v_bus - controller->v_ref);
benkatz 51:6cd89bd6fcaa 191 controller->fw_int = fmaxf(fminf(controller->fw_int, 0.0f), -I_FW_MAX);
benkatz 48:74a40481740c 192 controller->i_d_ref = controller->fw_int;
benkatz 48:74a40481740c 193 //float i_cmd_mag_sq = controller->i_d_ref*controller->i_d_ref + controller->i_q_ref*controller->i_q_ref;
benkatz 48:74a40481740c 194 limit_norm(&controller->i_d_ref, &controller->i_q_ref, I_MAX);
benkatz 25:f5741040c4bb 195
benkatz 47:e1196a851f76 196
benkatz 47:e1196a851f76 197
benkatz 25:f5741040c4bb 198 /// PI Controller ///
benkatz 22:60276ba87ac6 199 float i_d_error = controller->i_d_ref - controller->i_d;
benkatz 45:26801179208e 200 float i_q_error = controller->i_q_ref - controller->i_q;// + cogging_current;
benkatz 37:c0f352d6e8e3 201
benkatz 45:26801179208e 202 // Calculate feed-forward voltages //
benkatz 48:74a40481740c 203 float v_d_ff = SQRT3*(1.0f*controller->i_d_ref*R_PHASE - controller->dtheta_elec*L_Q*controller->i_q); //feed-forward voltages
benkatz 48:74a40481740c 204 float v_q_ff = SQRT3*(1.0f*controller->i_q_ref*R_PHASE + controller->dtheta_elec*(L_D*controller->i_d + 1.0f*WB));
benkatz 37:c0f352d6e8e3 205
benkatz 45:26801179208e 206 // Integrate Error //
benkatz 47:e1196a851f76 207 controller->d_int += controller->k_d*controller->ki_d*i_d_error;
benkatz 47:e1196a851f76 208 controller->q_int += controller->k_q*controller->ki_q*i_q_error;
benkatz 47:e1196a851f76 209
benkatz 47:e1196a851f76 210 controller->d_int = fmaxf(fminf(controller->d_int, OVERMODULATION*controller->v_bus), - OVERMODULATION*controller->v_bus);
benkatz 47:e1196a851f76 211 controller->q_int = fmaxf(fminf(controller->q_int, OVERMODULATION*controller->v_bus), - OVERMODULATION*controller->v_bus);
benkatz 47:e1196a851f76 212
benkatz 47:e1196a851f76 213 //limit_norm(&controller->d_int, &controller->q_int, OVERMODULATION*controller->v_bus);
benkatz 47:e1196a851f76 214 controller->v_d = controller->k_d*i_d_error + controller->d_int ;//+ v_d_ff;
benkatz 47:e1196a851f76 215 controller->v_q = controller->k_q*i_q_error + controller->q_int ;//+ v_q_ff;
benkatz 47:e1196a851f76 216
benkatz 47:e1196a851f76 217 controller->v_ref = sqrt(controller->v_d*controller->v_d + controller->v_q*controller->v_q);
benkatz 22:60276ba87ac6 218
benkatz 44:8040fa2fcb0d 219 limit_norm(&controller->v_d, &controller->v_q, OVERMODULATION*controller->v_bus); // Normalize voltage vector to lie within curcle of radius v_bus
benkatz 48:74a40481740c 220 float dtc_d = controller->v_d/controller->v_bus;
benkatz 48:74a40481740c 221 float dtc_q = controller->v_q/controller->v_bus;
benkatz 48:74a40481740c 222 linearize_dtc(&dtc_d);
benkatz 48:74a40481740c 223 linearize_dtc(&dtc_q);
benkatz 48:74a40481740c 224 controller->v_d = dtc_d*controller->v_bus;
benkatz 48:74a40481740c 225 controller->v_q = dtc_q*controller->v_bus;
benkatz 47:e1196a851f76 226 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
benkatz 22:60276ba87ac6 227 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
benkatz 22:60276ba87ac6 228
benkatz 25:f5741040c4bb 229 if(PHASE_ORDER){ // Check which phase order to use,
benkatz 31:61eb6ae28215 230 TIM1->CCR3 = (PWM_ARR)*(1.0f-controller->dtc_u); // Write duty cycles
benkatz 31:61eb6ae28215 231 TIM1->CCR2 = (PWM_ARR)*(1.0f-controller->dtc_v);
benkatz 31:61eb6ae28215 232 TIM1->CCR1 = (PWM_ARR)*(1.0f-controller->dtc_w);
benkatz 22:60276ba87ac6 233 }
benkatz 22:60276ba87ac6 234 else{
benkatz 32:ccac5da77844 235 TIM1->CCR3 = (PWM_ARR)*(1.0f-controller->dtc_u);
benkatz 32:ccac5da77844 236 TIM1->CCR1 = (PWM_ARR)*(1.0f-controller->dtc_v);
benkatz 32:ccac5da77844 237 TIM1->CCR2 = (PWM_ARR)*(1.0f-controller->dtc_w);
benkatz 22:60276ba87ac6 238 }
benkatz 25:f5741040c4bb 239
benkatz 48:74a40481740c 240 controller->theta_elec = theta;
benkatz 22:60276ba87ac6 241
benkatz 22:60276ba87ac6 242 }
benkatz 26:2b865c00d7e9 243
benkatz 26:2b865c00d7e9 244
benkatz 26:2b865c00d7e9 245 void torque_control(ControllerStruct *controller){
benkatz 28:8c7e29f719c5 246 float torque_ref = controller->kp*(controller->p_des - controller->theta_mech) + controller->t_ff + controller->kd*(controller->v_des - controller->dtheta_mech);
benkatz 26:2b865c00d7e9 247 //float torque_ref = -.1*(controller->p_des - controller->theta_mech);
benkatz 26:2b865c00d7e9 248 controller->i_q_ref = torque_ref/KT_OUT;
benkatz 37:c0f352d6e8e3 249 controller->i_d_ref = 0.0f;
benkatz 26:2b865c00d7e9 250 }
benkatz 47:e1196a851f76 251