In Pulse-Width-Modulated (PWM) inverters, dead-time and voltage drops lead to a distortion on the average output voltage. This effect is related to the system parameters and to the operating conditions and in many drives applications it can be intolerable. A number of modeling approaches and compensation methods have been proposed in the past literature. A recent approach adopts an accurate physical model of the inverter, aiming at investigating the effects of parasitic capacitances and devices voltage drops by a fitting analytical characteristic. Model parameters are derived from a self-commissioning procedure, based on proper voltage injection and processing, both affecting the accuracy of achievable compensation. In this paper, these issues have been considered and two original enhancements have been proposed and validated, demonstrating the superiority of the results over state-of-the-art. Finally, the effects of the mentioned inverter distortion on the accuracy of current sampling and control loops are also analyzed for the first time, and an original compensation strategy is proposed and validated. Theoretical analysis and developments are fully reported, together with accurate simulations and experimental results based on a commercial drive.
Advances on Analysis, Modeling and Accurate Self-Commissioning Compensation of Inverter Dead-Time Distortion Based on a Physical Model
Biason M.;Calligaro S.;Iurich M.;Petrella R.;Shahdadi A.
2021-01-01
Abstract
In Pulse-Width-Modulated (PWM) inverters, dead-time and voltage drops lead to a distortion on the average output voltage. This effect is related to the system parameters and to the operating conditions and in many drives applications it can be intolerable. A number of modeling approaches and compensation methods have been proposed in the past literature. A recent approach adopts an accurate physical model of the inverter, aiming at investigating the effects of parasitic capacitances and devices voltage drops by a fitting analytical characteristic. Model parameters are derived from a self-commissioning procedure, based on proper voltage injection and processing, both affecting the accuracy of achievable compensation. In this paper, these issues have been considered and two original enhancements have been proposed and validated, demonstrating the superiority of the results over state-of-the-art. Finally, the effects of the mentioned inverter distortion on the accuracy of current sampling and control loops are also analyzed for the first time, and an original compensation strategy is proposed and validated. Theoretical analysis and developments are fully reported, together with accurate simulations and experimental results based on a commercial drive.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.