A Novel Modulation Method to Suppress the Current Zero-Crossing Distortion for Vienna Rectifier With Different Control Methods Under Unbalanced Grid

An Improved Zero-Current Distortion Compensation Method for the Soft-Start of the Vienna Rectifier

“…If the length of the UR is long, the ZCD seriously occurs, increasing THD and leading to a degradation of power quality. Several methods of the Vienna rectifier to avoid the ZCD and to improve power quality have been previously proposed [11][12][13][14][15][16][17][18][19][20][21]. Each method is suggested with a focus on a specific purpose as well as a common purpose to mitigate the ZCD.…”

“…Each method is suggested with a focus on a specific purpose as well as a common purpose to mitigate the ZCD. The ZCD compensation (ZCDC) methods proposed in [12][13][14][15][16] are based on the space vector pulse width modulation (SVPWM) method which allows a flexible voltage modulation. In [13], a ZCDC method is proposed which is focused on improving the performance of ZCDC by considering and compensating for the detection error of the sign of the phase current.…”

“…The ZCDC method in [14] covers both the control of the neutral point voltage and compensation of the ZCD. In [16], a ZCDC method is proposed which can maintain its performance even under an unbalanced grid by introducing separation control for positive and negative sequence components of grid voltage and current. The methods proposed in [11,17,18] stand on the basis of the carrier-based PWM (CB-PWM) method, which can be simply implemented in that it has a relatively lower amount of computation compared to the SVPWM method.…”

“…Most of these ZCDC methods [11][12][13][14][16][17][18][19][20][21] adopt a common approach of injecting an offset voltage to the reference voltages to compensate for the ZCD. However, the reference voltages occasionally exceed the linear modulation region by the offset voltage added at the driving start-point of the Vienna rectifier, where the modulation index (MI) of phase voltage is relatively large.…”

“…The IZCDC component is derived from an equation for the variance of the phase current. The phase where the IZCDC is applied is determined depending on the sector defined according to the phase Several methods of the Vienna rectifier to avoid the ZCD and to improve power quality have been previously proposed [11][12][13][14][15][16][17][18][19][20][21]. Each method is suggested with a focus on a specific purpose as well as a common purpose to mitigate the ZCD.…”