[参考译文] TMS320F2800157：面对模块过流故障

https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/1614831/tms320f2800157-facing-module-over-current-fault

器件型号： TMS320F2800157

您好、请参阅此数据、模块过流故障在不同的测试场景中发生。 请帮助我们分析并找出解决此问题的根本原因。

总增益≈12.72

Vmax = 3.3V

Vsmax= Vmax/GAIN=3.3/12.72=0.2594339622641509

IMAX = Vsmax/Rshunt = 0.2594339622641509 / 0.0003

I（满量程电流）= 864.77A

overCurrent_A =

  (objSets->overCurrent_A > objSets->maxPeakCurrent_A)？

    objSets->maxPeakCurrent_A : objSets->overCurrent_A ;

USER_MOTOR1_OVER_CURRENT_A = 500.0A

USER_M1_ADC_FULL_SCALE_CURRENT_A = 864.888A

objSets->maxPeakCurrent_A = 864.888 * 0.475 = 410.82A

0.475 =安全裕度系数

overCurrent_A =最小值 (500,410.82)

overCurrent_A = 410.82A

objSets->currentInv_sf = 4096/USER_M1_ADC_FULL_SCALE_CURRENT_A；

currentInv_sf=4096/864.888=4.735

cmpValue = overCurrent_A * currentInv_sf；

cmpValue=410.82×4.735≈1944

410.82A→1944 ADC 计数

处于三分流器模式：

USER_M1_IS_OFFSET_CMPSS =(2048+2048+2048)/3 = 2048

dacCMPValH = 2048 + 1944 = 3992

dacCMPValL = 2048 - 1944 = 104

CMPSS_setDACValueHigh (...、3992)；

CMPSS_setDACValueLow (...、104)；

在以下情况下、CMPSS 设置为跳闸：ADC < 104  或  ADC > 3992