| Title |
Dual Current Control Scheme of a Grid-connected Inverter for Power Quality Improvement in Distributed Generation Systems |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2015.29.9.033 |
| Keywords |
Distorted Grid ; Distributed Generation ; Dual Current Control ; Grid-Connected Inverter ; Harmonic Compensation |
| Abstract |
To improve the power quality of distributed generation (DG) systems even in the presence of distorted grid condition, dual current control scheme of a grid-connected inverter is proposed. The proposed current control scheme is achieved by decomposing the inverter state equations into the fundamental and harmonic components. The derived models are employed to design dual current controllers. The conventional PI decoupling current controller is used in the fundamental model to control the main power flow in DG systems. At the same time, the predictive control is applied in the harmonic model to suppress undesired harmonic currents to zero quickly. To decompose the voltage inputs and state variables into the fundamental and harmonic components, the fourth order band pass filter (BPF) is designed in the discrete-time domain for a digital implementation. For experimental verification, 2kVA prototype of a grid-connected inverter has been constructed using digital signal processor (DSP) TMS320F28335. The effectiveness of the proposed strategy is demonstrated through comparative simulation and experimental results. |