AN2531

Freescale Semiconductor, Inc. Application Note AN2531/D Rev. 0, 5/2003 Standard Space Vector Modulation with Dead-Time Correction – XOR version TPU Function Set (svmStdDtXor) By Milan Brejl, Ph.D. Freescale Semiconductor, Inc... Functional Overview The Standard Space Vector Modulation with Dead-Time Correction – XOR version (svmStdDtXor) is a version of the Standard Space Vector Modulation with Dead-Time Correction (svmStdDt) function that uses two TPU channels to generate one PWM output channel. The TPU channel outputs are connected to an XOR gate whos output is the required PWM signal. See Figure 1. An advantage of this solution is the full range 0% to 100% of PWM duty-cycle ratios. There is no MPW (minimum pulse width) parameter to limit the edge duty-cycle ratios in this version, unlike in the svmStdDt. A disadvantage is that the number of assigned TPU channels is doubled. AT1 XOR Phase A - top AT2 AB1 AB2 XOR Phase A - bottom BT1 XOR Phase B - top BT2 BB1 XOR Phase B - bottom BB2 CT1 XOR Phase C - top CT2 CB1 XOR Phase C - bottom CB2 Figure 1. Functionality of XOR version – illustration © Motorola, Inc., 2003 For More Information On This Product, Go to: www.freescale.com Freescale Semiconductor, Inc. AN2531/D The dead-time correction technique requires knowledge of the instantaneous direction of phase currents. In the case of positive phase current the top channel high-time is equal to the calculated high-time and the bottom channel has to control...