An enhanced pulse-based dead-time compensation technique for PWM-VSI drives

Abstract

A dead-time delay is imperative in pulse width modulated (PWM) voltage source inverters in order to prevent a shoot through in the DC link. This delay causes the dead time effect and it results in output waveform distortions. This leads to various undesired characteristics. A simple yet an accurate pulse based dead time compensation technique is presented in this paper which compensates the dead time effect accurately without any phase delays at the output. Proposed method is developed by analyzing both magnitude and phase distortions in a pulse by pulse manner. Simulation results of the proposed method are provided in order to verify the validity of the method. Index Terms-Dead time compensation, pulse based, phase lag, PWM inverter.

Dead time compensation for three-level flying capacitor inverter with phase shift PWM

“…Many reports have focused on dead time analysis and proposed compensation method for two level inverter. As reported previously [1]- [5], dead time effect can be eliminated by pulse based compensation. PWM signal is adjusted based on current polarity, and current detection as a resuly is important.…”

“…where V dc is DC link voltage , Td is dead time period, and f s is carrier frequency , sgn(i u ) is sign function and given as (5).…”

Improved dead-time elimination method for three-phase power inverters

“…In these methods, the voltage error is detected and then corrected in the next pulse. This delay in the voltage correction is considered as the main drawback of these methods [12].…”