TI中文支持网Part Number:TMS320F280049C
图1：逆变器电路拓扑
PWM1A和PWM1B输出互补，开关频率66kHz,PWM2A和PWM2B输出互补，开关频率50Hz。在逆变电压正半周时，PWM2A输出为低，PWM2B输出为高PWM1A占空比按正弦规律变化，PWM1B和PWM1A互补。在逆变电压负半周时，PWM2A输出为高，PWM2B输出为低，PWM1B占空比按正弦规律变化，PWM1A和PWM1B互补。
图2：过零点驱动异常波形a
图2中橙色正弦波为逆变电压波形，蓝色为PWM2A波形，黄色为PWM1A波形，绿色为PWM1B波形。
图3：过零点驱动异常（图2波形过零点处展开后的驱动细节）
异常出现没发现什么规律,有时一分钟可以出现一到两次，有时几十分钟没有出现一次。出现异常时PWM2A的波形会提前一个高频开关周期翻转，或者是PWM1A延后1个周期翻转，具体不清楚是谁延迟了谁提前了。
PWM底层配置代码如下
EALLOW;
EPwm1Regs.TZSEL.all=0;
EPwm1Regs.TZCTL.bit.TZA = TZ_FORCE_LO; // EPWMxA will go low
EPwm1Regs.TZCTL.bit.TZB = TZ_FORCE_LO; // EPWMxB will go low
EPwm1Regs.TZFRC.bit.OST=1;
EPwm2Regs.TZSEL.all=0;
EPwm2Regs.TZCTL.bit.TZA = TZ_FORCE_LO; // EPWMxA will go low
EPwm2Regs.TZCTL.bit.TZB = TZ_FORCE_LO; // EPWMxB will go low
EPwm2Regs.TZFRC.bit.OST=1;
CpuSysRegs.PCLKCR0.bit.TBCLKSYNC = 0;
EPwm1Regs.ETSEL.bit.SOCAEN = 1; // Enable SOC on A group
EPwm1Regs.ETSEL.bit.SOCASEL= 1; // Select SOC from from CPMA onupcount
EPwm1Regs.ETPS.bit.SOCAPRD = 3; // Generate pulse on 3st event//三个开关周期触发一次采样信号
EPwm1Regs.TBPRD = 757 ; //周期
EPwm1Regs.TBPHS.bit.TBPHS=0;//设置相位
EPwm1Regs.TBCTR = 0;//计数器
EPwm1Regs.TBCTL.bit.PRDLD = TB_SHADOW;//使能影子寄存器自动重载
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN;//向上向下计数模式
EPwm1Regs.TBCTL.bit.PHSEN=TB_DISABLE;//失能相位功能
EPwm1Regs.TBCTL.bit.PHSDIR=TB_UP;//同步后计数器向上计数
EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1;//TBCLK = EPWMCLK / (HSPCLKDIV x CLKDIV).
EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;
EPwm1Regs.TBCTL.bit.SYNCOSEL =TB_CTR_ZERO;//计数到0时输出同步信号
EPwm1Regs.CMPA.bit.CMPA = 1; // set duty 0% initially
EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;//CC_SHADOW：影子模式；CC_IMMEDIATE：立即模式
EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;//计数比较器A等于0时从影子寄存器重载值
EPwm1Regs.AQCTLA.all = 0; // set to take no action
EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;//向上计数时 TBCTR = CMPA 时的动作
EPwm1Regs.AQCTLA.bit.CAD = AQ_SET; //向下计数时 TBCTR = CMPA 时的动作
EPwm1Regs.AQCTLA.bit.ZRO = AQ_NO_ACTION; //TBCTR = 0的动作
EPwm1Regs.DBCTL.bit.IN_MODE = DBA_ALL;//EPWMxA 为死区模块的输入源
EPwm1Regs.DBCTL.bit.DEDB_MODE = 0;//A的上升沿延迟，B的下降沿延迟
EPwm1Regs.DBCTL.bit.POLSEL = DB_ACTV_HIC;//EPWMxA不反向，EPWMxB反向
EPwm1Regs.DBCTL.bit.OUT_MODE =DB_FULL_ENABLE;//上升沿和下降沿均延迟
EPwm1Regs.DBRED.all = 10;//上升沿延迟时钟数（死区100ns）
EPwm1Regs.DBFED.all = 10;//下降沿延迟时钟数
EPwm1Regs.CMPA.bit.CMPAHR = 0; // initialize HRPWM extension
EPwm1Regs.HRCNFG.all = 0x0;
EPwm1Regs.HRCNFG.bit.EDGMODE = HR_FEP; // MEP control on falling edge
EPwm1Regs.HRCNFG.bit.CTLMODE = HR_CMP;
EPwm1Regs.HRCNFG.bit.HRLOAD = HR_CTR_ZERO;
EPwm1Regs.HRCNFG.bit.EDGMODEB = HR_FEP; // MEP control on falling edge
EPwm1Regs.HRCNFG.bit.CTLMODEB = HR_CMP;
EPwm1Regs.HRCNFG.bit.HRLOADB = HR_CTR_ZERO;
EPwm1Regs.HRPCTL.bit.HRPE = 0; // Turn off high-resolution period
SyncSocRegs.SYNCSELECT.bit.SYNCOUT = 0;//EPWM1SYNCOUT selected to drive the SYNCOUT pin.
////EPwm2//////////////////////////////////////////////////////////////
EPwm2Regs.TBPRD = 757; // TBPRD=CPU frequency/PWM frequency/2
EPwm2Regs.TBPHS.bit.TBPHS = 0;//INV_PWM_PERIOD;//相位寄存器
EPwm2Regs.TBCTR = 0;//计数器
EPwm2Regs.TBCTL.bit.PRDLD = TB_SHADOW;//使能影子寄存器
EPwm2Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN;//计数模式向上向下方式
EPwm2Regs.TBCTL.bit.PHSEN = TB_ENABLE;//TB_DISABLE;//关闭相位功能,如果使用相位寄存器，即便TBPHS=0也会延迟一个时钟周期
EPwm2Regs.TBCTL.bit.PHSDIR=TB_UP;//同步后计数器向上计数
EPwm2Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1;
EPwm2Regs.TBCTL.bit.CLKDIV = TB_DIV1;
EPwm2Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN;//同步PWM1输出的同步信号，使能相位寄存器才生效
// Counter Compare Submodule Registers
EPwm2Regs.CMPA.bit.CMPA = 1; // set duty 0% initially
EPwm2Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;//CC_SHADOW;//计数比较器A设置为影子模式
EPwm2Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;//计数比较器A等于0时从影子寄存器重载值
EPwm2Regs.AQCTLA.all=0;
EPwm2Regs.AQCTLA.bit.CAU = AQ_CLEAR;//AQ_NO_ACTION;
EPwm2Regs.AQCTLA.bit.CAD = AQ_NO_ACTION;
EPwm2Regs.AQCTLA.bit.ZRO = AQ_NO_ACTION;
// Active high complementary PWMs – Set up thedeadband
EPwm2Regs.DBCTL.bit.IN_MODE = DBA_ALL;//0x0
EPwm2Regs.DBCTL.bit.DEDB_MODE = 0;
EPwm2Regs.DBCTL.bit.POLSEL = DB_ACTV_HIC;//0x2
EPwm2Regs.DBCTL.bit.OUT_MODE = DB_FULL_ENABLE;//0x3
EPwm2Regs.DBRED.all =20;//上升沿死区时钟数(200ns)
EPwm2Regs.DBFED.all =20;//下降沿死区时钟数
CpuSysRegs.PCLKCR0.bit.TBCLKSYNC = 1;
EPwm1Regs.TZCLR.bit.DCAEVT2=1;
EPwm2Regs.TZCLR.bit.DCAEVT2=1;
EPwm1Regs.TZCLR.bit.CBC=1;
EPwm2Regs.TZCLR.bit.CBC=1;
EDIS;
中断中更新驱动代码如下：
EPwm1Regs.CMPA.bit.CMPA= dutyCMPA;//按正弦规律变化的占空比
EPwm2Regs.CMPA.bit.CMPA= 1;
//InvSine是0-2π正弦值
if(InvSine>=0.0f)//电压正半周
{
EPwm2Regs.AQCTLA.bit.CAU = AQ_CLEAR;
EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;
EPwm1Regs.AQCTLA.bit.CAD = AQ_SET;
EPwm1Regs.AQCTLA.bit.ZRO = AQ_SET;
}else{//电压负半周
EPwm2Regs.AQCTLA.bit.CAU = AQ_SET;
EPwm1Regs.AQCTLA.bit.CAU = AQ_SET;
EPwm1Regs.AQCTLA.bit.CAD = AQ_CLEAR;
EPwm1Regs.AQCTLA.bit.ZRO = AQ_CLEAR;
}
Barbecue：
能否通过DO监测一下 InvSine 信号的变化情况，并与图2中的信号进行对比？
EPwm2是否设置有同步源呢？
