Harmonics and unbalanced load compensation by a modular multilevel cascaded converter active power conditioner

• Published in: Journal of engineering (Stevenage, England) Vol. 2019; no. 17; pp. 3778 - 3783
• Main Authors: Huang, Han, Oghorada, O.J.K, Zhang, Li, Chong, B.V.P
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 01.06.2019; Wiley
• Subjects: active filters; current harmonics; electric current control; harmonic distortion; inter-cluster; intra-cluster voltage balance control; load current distortion; MMCC-APC; modified predictive current controller; modular multilevel cascaded converter active power conditioner; novel control scheme; power convertors; power harmonic filters; power network; power supply quality; predictive control; reactive load; reactive power; static VAr compensators; The 9th International Conference on Power Electronics, Machines and Drives (PEMD 2018); thyristors; unbalanced load compensation; unbalanced load current; unbalanced thyristor controlled rectifier; voltage control; current harmonics; unbalanced load current; power convertors; static VAr compensators; load current distortion; reactive load; power harmonic filters; harmonic distortion; intra-cluster voltage balance control; electric current control; modified predictive current controller; modular multilevel cascaded converter active power conditioner; active filters; power supply quality; power network; thyristors; MMCC-APC; unbalanced load compensation; reactive power; unbalanced thyristor controlled rectifier; novel control scheme; predictive control; voltage control; inter-cluster
• ISSN: 2051-3305; 2051-3305
• DOI: 10.1049/joe.2018.8144

This paper presents a novel control scheme for a modular multilevel cascaded converter (MMCC) functioning as an active power conditioner (APC) to control the reactive power, eliminate the current harmonics, and compensate unbalanced load current simultaneously. This combines a modified predictive current controller with the inter-cluster and intra-cluster voltage balance control for MMCC sub-module capacitors. Simulation studies of this MMCC-APC for a power network containing both an unbalanced thyristor controlled rectifier and a reactive load are performed and results verifying its performance under varying degrees of load current distortion measured by THD levels are presented.