Direct grid‐side current model predictive control for grid‐connected inverter with LCL filter

Abstract

On control of the grid-connected inverter (GCI) with LCL filter, the inverter-side current model predictive control is adopted conventionally. The ultimate grid-side current is controlled indirectly by control of inverter-side current. The ideal scenario is that grid-side current is directly controlled. However, the conventional control model is complicated and the calculation is heavy. This study proposed a novel direct grid-side current model predictive control (GSC-MPC) for GCI with LCL filter. Based on timing coordination of both forward and backward difference methods, a direct connection is established between the grid-side output current and the inverter-side output voltage. Meanwhile, a proper mathematical model is built for an improved model predictive control. The exact required voltage vector in the next sampling interval is predicted and calculated by this model. The output optimal voltage vector is modulated by space vector pulse width modulation technique to control the inverter. Furthermore, the proposed GSC-MPC is rather robust to parameter variation. Simulation and experimental results present that the proposed GSC-MPC can improve the current control performance effectively for GCI with LCL filter.

Voltage Source Operation of the Energy-Router Based on Model Predictive Control

“…Thus, we only have predefined passive components of the LCL filter and in the case of acceptable tolerance (10%-20%) we do need any identification. Many research papers have addressed the grid-connected systems [34][35][36][37][38][39]. At the same time, none of them address no-load or idle operation of the inverter.…”

High Performance Decoupling Current Control by Linear Extended State Observer for Three-Phase Grid-Connected Inverter With an LCL Filter

“…Singleinductance filters, which are of large volume and weight, not only cost a lot but also significantly increase the loss. Given the problems, single-inductance filters are usually replaced with LCL filters in high-power inverters [2]- [5].…”

Comparison of Current Control Strategies Based on FCS-MPC and D-PI-PWM Control for Actively Damped VSCs With LCL-Filters

“…Its uniqueness include the time-domain approach, predictive nature, and cost-function-based control feature. Two basic variants of MPC with active-damping consideration have been reported to date: finite-control-set (FCS) MPC [25]- [29] and continuous-control-set (CCS) MPC [30]. Authors in [25]- [28] have investigated the possibilities of appending the virtual resistance based active damping techniques to FCS-MPC.…”

“…FCS-MPC schemes with two prediction horizons that simultaneously control three-vector-variables (i.e. complex variables) consisting the converter current vector, grid current vector, and capacitor voltage vectors, are proposed in [27], [29]. On the other hand, [28] showed that a twovector-variables cost function can readily provide active damping without virtual-resistance method, and that the converter switching frequency can be directly manipulated through a weighted cost function.…”