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Controlling Zero Voltage Switched Full Bridge (ZVSFB) Converter
Example 3-6. Code Snippet for Configuration in Figure 3-15
//=====================================================================
// Config
//=====================================================================
// Initialization Time
//========================
// EPWM Module 1 config
EPwm1Regs.TBPRD = 1200; // Period = 1201 TBCLK counts
EPwm1Regs.CMPA = 600; // Set 50% fixed duty for EPWM1A
EPwm1Regs.TBPHS = 0; // Set Phase register to zero
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Asymmetrical mode
EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE; // Master module
EPwm1Regs.TBCTL.bit.PRDLD = TB_SHADOW;
EPwm1Regs.TBCTL.bit.SYNCOSEL = TB_CTR_ZERO; // Sync down-stream module
EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;
EPwm1Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;
EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO; // load on CTR=Zero
EPwm1Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO; // load on CTR=Zero
EPwm1Regs.AQCTLA.bit.ZRO = AQ_SET; // set actions for EPWM1A
EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;
EPwm1Regs.DBCTL.bit.MODE = DB_FULL_ENABLE; // enable Dead-band module
EPwm1Regs.DBCTL.bit.POLSEL = DB_ACTV_HIC; // Active Hi complementary
EPwm1Regs.DBFED = 50; // FED = 50 TBCLKs initially
EPwm1Regs.DBRED = 70; // RED = 70 TBCLKs initially
// EPWM Module 2 config
EPwm2Regs.TBPRD = 1200; // Period = 1201 TBCLK counts
EPwm2Regs.CMPA.half.CMPA = 600; // Set 50% fixed duty EPWM2A
EPwm2Regs.TBPHS = 0; // Set Phase register to zero initially
EPwm2Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Asymmetrical mode
EPwm2Regs.TBCTL.bit.PHSEN = TB_ENABLE; // Slave module
EPwm2Regs.TBCTL.bit.PRDLD = TB_SHADOW;
EPwm2Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // sync flow-through
EPwm2Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;
EPwm2Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;
EPwm2Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO; // load on CTR=Zero
EPwm2Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO; // load on CTR=Zero
EPwm2Regs.AQCTLA.bit.ZRO = AQ_SET; // set actions for EPWM2A
EPwm2Regs.AQCTLA.bit.CAU = AQ_CLEAR;
EPwm2Regs.DBCTL.bit.MODE = DB_FULL_ENABLE; // enable Dead-band module
EPwm2Regs.DBCTL.bit.POLSEL = DB_ACTV_HIC; // Active Hi complementary
EPwm2Regs.DBFED = 30; // FED = 30 TBCLKs initially
EPwm2Regs.DBRED = 40; // RED = 40 TBCLKs initially
// Run Time (Note: Example execution of one run-time instant)
//============================================================
EPwm2Regs.TBPHS = 1200-300; // Set Phase reg to 300/1200 * 360 = 90 deg
EPwm1Regs.DBFED = FED1_NewValue; // Update ZVS transition interval
EPwm1Regs.DBRED = RED1_NewValue; // Update ZVS transition interval
EPwm2Regs.DBFED = FED2_NewValue; // Update ZVS transition interval
EPwm2Regs.DBRED = RED2_NewValue; // Update ZVS transition interval
EPwm1Regs.CMPB = 200; // adjust point-in-time for ADCSOC trigger
SPRU791D November 2004 Revised October 2007 Applications to Power Topologies 91
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