Generalized PWM-Based Method for Multiphase Neutral-Point-Clamped Converters with Capacitor Voltage Balance Capability
Date
2016Keywords
Voltage control
Space vector pulse width modulation
Switches
Clamps
Phase modulation
Electronic mail
Abstract
This paper presents a generalized PWM-based control algorithm for multiphase neutral-point-clamped (NPC) converters. The proposed algorithm provides a zero-sequence to be added to the reference voltages that contributes to improve the performance of the converter by: i) regulating the neutralpoint (NP) current to eliminate/attenuate the low-frequency NP voltage ripples, ii) reducing the switching losses of the power semiconductors and iii) maximizing the range of modulation indices for linear operation mode. The control method is formulated following a carrier-based PWM approach. Hence, dealing with complex space-vector diagrams to solve the modulation problem for multiphase converters is avoided. The recursive approach means that it can be easily extended to n-phase converters without increasing the complexity and computational burden, making it especially attractive for digital implementation. The proposed method allows regulating the NP voltage without the need for external controllers; ...
Type
article