大家好!
配置3个 ePWM 之间的相移以驱动3个升压功率级时遇到问题。
我希望每个 ePWM 具有120°相移(相位是输入用户)。 我将 EPWM1配置为主器件、将 EPWM2和 EPWM3配置为从器件。 但在我的示波器上、我看到每相60°、而不是120°。 请你解释一下。 为什么它不能正常工作?
谢谢。
void epwm_init(uint32_t base) { float PWM_TBPRD_1; float PWM_TBPRD_2; float PWM_TBPRD_3; float PWM_CMPA_1; float PWM_CMPA_2; float PWM_CMPA_3; EPWM_ClockDivider PWM_PARAM_PRESCALER; EPWM_HSClockDivider PWM_PARAM_HIGHSPEEDPRESCALER; float TBCLK; if(base == myEPWM1_BASE) { get_pwm_clock_from_freq(base , &PWM_TBPRD_1 , &PWM_TBPRD_2 , &PWM_TBPRD_3 , &PWM_CMPA_1 , &PWM_CMPA_2 , &PWM_CMPA_3 , &PWM_PARAM_PRESCALER , &PWM_PARAM_HIGHSPEEDPRESCALER, &TBCLK); // Parameters EPWM_setTimeBasePeriod(base, (uint16_t)PWM_TBPRD_1); EPWM_setCounterCompareValue(base, EPWM_COUNTER_COMPARE_B, (uint16_t)PWM_CMPA_1); EPWM_setPhaseShift(base, 0U); EPWM_disablePhaseShiftLoad(base); EPWM_setTimeBaseCounter(base, 0U); EPWM_enableSyncOutPulseSource(myEPWM1_BASE, EPWM_SYNC_OUT_PULSE_ON_CNTR_ZERO); } else if (base == myEPWM2_BASE) { get_pwm_clock_from_freq(base , &PWM_TBPRD_1 , &PWM_TBPRD_2 , &PWM_TBPRD_3 , &PWM_CMPA_1 , &PWM_CMPA_2 , &PWM_CMPA_3 , &PWM_PARAM_PRESCALER , &PWM_PARAM_HIGHSPEEDPRESCALER, &TBCLK); // Parameters EPWM_setTimeBasePeriod(base, (uint16_t)PWM_TBPRD_2); EPWM_setCounterCompareValue(base, EPWM_COUNTER_COMPARE_A, (uint16_t)PWM_CMPA_2); EPWM_setPhaseShift(base, 0U); EPWM_disablePhaseShiftLoad(base); EPWM_setTimeBaseCounter(base, 0U); EPWM_setSyncInPulseSource(base, EPWM_SYNC_IN_PULSE_SRC_SYNCOUT_EPWM1); set_phase(base, PHI); } else if(base == myEPWM3_BASE) { get_pwm_clock_from_freq(base , &PWM_TBPRD_1 , &PWM_TBPRD_2 , &PWM_TBPRD_3 , &PWM_CMPA_1 , &PWM_CMPA_2 , &PWM_CMPA_3 , &PWM_PARAM_PRESCALER , &PWM_PARAM_HIGHSPEEDPRESCALER, &TBCLK); // Parameters EPWM_setTimeBasePeriod(base, (uint16_t)PWM_TBPRD_3); EPWM_setCounterCompareValue(base, EPWM_COUNTER_COMPARE_A, (uint16_t)PWM_CMPA_3); EPWM_setPhaseShift(base, 0U); EPWM_disablePhaseShiftLoad(base); EPWM_setTimeBaseCounter(base, 0U); EPWM_setSyncInPulseSource(base, EPWM_SYNC_IN_PULSE_SRC_SYNCOUT_EPWM1); //EPWM_enableSyncOutPulseSource(myEPWM1_BASE, EPWM_SYNC_OUT_PULSE_ON_CNTR_ZERO); set_phase(base, PHI); } //EPWM_setTimeBaseCounter(base, 0U); EPWM_setTimeBaseCounterMode(base, EPWM_COUNTER_MODE_UP_DOWN); EPWM_setClockPrescaler(base, PWM_PARAM_PRESCALER, PWM_PARAM_HIGHSPEEDPRESCALER); // Set up shadowing EPWM_setCounterCompareShadowLoadMode(base, EPWM_COUNTER_COMPARE_A, EPWM_COMP_LOAD_ON_CNTR_ZERO); // Set actions EPWM_setActionQualifierAction(base, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_HIGH, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA); EPWM_setActionQualifierAction(base, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_LOW, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA); EPWM_setActionQualifierAction(base, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_HIGH, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA); EPWM_setActionQualifierAction(base, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_LOW, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA); // Trip zone // Configure ePWM1x to output low on TZx TRIP EPWM_setTripZoneAction(base, EPWM_TZ_ACTION_EVENT_TZA, EPWM_TZ_ACTION_LOW); EPWM_setTripZoneAction(base, EPWM_TZ_ACTION_EVENT_TZB, EPWM_TZ_ACTION_LOW); // Trigger event when DCBH is high EPWM_setTripZoneDigitalCompareEventCondition(base, EPWM_TZ_DC_OUTPUT_B1, EPWM_TZ_EVENT_DCXH_HIGH); // Configure DCBH to use TRIP4 as an input EPWM_enableDigitalCompareTripCombinationInput(base, EPWM_DC_COMBINATIONAL_TRIPIN4, EPWM_DC_TYPE_DCBH); // Enable DCB as OST EPWM_enableTripZoneSignals(base, EPWM_TZ_SIGNAL_DCBEVT1); // Configure the DCB path to be unfiltered and asynchronous EPWM_setDigitalCompareEventSource(base, EPWM_DC_MODULE_B, EPWM_DC_EVENT_1, EPWM_DC_EVENT_SOURCE_ORIG_SIGNAL); // Clear trip flags EPWM_clearTripZoneFlag(base, EPWM_TZ_INTERRUPT | EPWM_TZ_FLAG_OST); // Calculate delays get_delays_FED_RED(myEPWM1_BASE, &TBCLK); get_delays_FED_RED(myEPWM2_BASE, &TBCLK); get_delays_FED_RED(myEPWM3_BASE, &TBCLK); }
void set_phase(uint32_t base, uint16_t phi) { uint16_t phase; if(base == myEPWM2_BASE) { phase = ((float)phi * HWREGH(base + EPWM_O_TBPRD) / 360); } if(base == myEPWM3_BASE) { phase = ((float)phi * HWREGH(base + EPWM_O_TBPRD) * 2 / 360); } //EPWM_selectPeriodLoadEvent(base, EPWM_SHADOW_LOAD_MODE_SYNC); EPWM_enableSyncOutPulseSource(base, EPWM_SYNC_OUT_PULSE_ON_SOFTWARE); EPWM_forceSyncPulse(base); EPWM_setPhaseShift(base, phase); EPWM_setTimeBaseCounter(base, phase); EPWM_enablePhaseShiftLoad(base); }
Damien