Pulse-based dead-time compensator for PWM voltage inverters

Abstract

The dead time necessary to prevent the short circuit of the power supply in pulse width modulated (PWM) voltage inverters results in output voltage deviations. Although individually small, when accumulated over an operating cycle, the voltage deviations are sufficient to distort the applied PWM signal. This paper presents a new method to correct for the dead time deviations. The Pulse Based Compensator is less hardware and software intensive than other dead time compensation methods providing a low cost solution. The pulse based technique is developed by analyzing the effects of dead time on a pulse by pulse basis and correcting each pulse accordingly. The technique is evaluated through simulation and experimental results. Other compensation methods are evaluated and the results compared with the pulse based technique. This comparison indicates previous methods can produce magnitude and phase errors in the applied terminal voltage, whereas the proposed method compensates for the dead time without significant magnitude and phase errors in the terminal voltage of PWM voltage source inverters.

A Dead Time Compensation Algorithm of Independent Multi-Phase PMSM with Three-Dimensional Space Vector Control

“…The switching leg time is averaged over an entire cycle and added to the voltage reference [6], [7]. A pulse-based method [8] compensates the dead time for each PWM pulse. These methods are dependent on the direction of the phase current.…”

“…The compensation methods of the dead time effects for the Y-connected 3-phase machine have already been suggested in many technical literatures [6]- [17]. The average value of the lost voltage calculation [6], [7], the PWM pulse based method [8], the voltage feed forward method [9]- [13], the phase angle calculation method [14], the disturbance observer method [15], [16], and the support vector regression (SVR) method [17] are the main categories of the conventional dead time compensation methods. However, these methods are based on the Y-connected three-phase machine and have drawbacks such as parameter dependency and complexity.…”

Dead-time effects on the voltage spectrum of a PWM inverter

“…Previous investigations into the effects of dead time have largely been examinations of its effects on time-domain representations of the voltage and current waveforms and attempts to mitigate these through re-adjustment of the inverter (Leggate & Kerkman, 1997;Lin, 2002;Munoz & Lipo, 1999;Murai et al, 1992;Oliviera et al, 2007). That is not to say there have been no previous attempts to calculate the effects of dead time on the harmonic spectrum, but such ventures have employed additional approximations or unnecessarily restrictive assumptions about the switching times (Chierchie & Paolini, 2010;Wu et al, 1999).…”

Online Dead Time Effect Compensation Algorithm of PWM Inverter for Motor Drive Using PR Controller

“…The lost voltage average value calculation [2,3], the pulse width modulation(PWM) pulse based technique [6]. voltage feed forward method [7][8][9][10][11][12], and the support vector regression(SVR) method [13] are the main categories of the conventional dead time compensation methods.…”

“…Since these undesirable ripples bring about bad influences to motor driving system, a compensation algorithm must be needed in the control algorithm of the motor drive. To solve the nonlinear characteristics of the VSI, various solutions have already been suggested [1][2][3][4][5][6][7][8][9][10][11][12][13]. The lost voltage average value calculation [2,3], the pulse width modulation(PWM) pulse based technique [6].…”