Model Predictive Current Control of Multilevel Smart Load Based on MPUC7 Converter

Amirabbas Kaymanesh,Ambrish Chandra,Mohammad Babaie,Kamal Al-Haddad

doi:10.1109/access.2021.3113630

Abstract

Considering the poor power quality performance of a two-level capacitor-based electric spring (ES1), this article presents a high-power density multilevel ES1 configuration based on a seven-level modified packed U-cell converter (MPUC7-ES1). A novel control strategy based on finite control-set model predictive current control (FCS-MPCC) is also proposed for MPUC7-ES1 application. This algorithm is designed to predict the system behavior for all the conceivable switching vectors based on the discrete models of MPUC7-ES1 that is developed for the first time. To guarantee a desirable operation, the main control objectives are the MPUC7-ES1 current, auxiliary capacitors’ voltages, and switching frequency reduction. Compared with the conventional ES1 control methods, the proposed strategy has key merits including considering the dynamic models of ES1 converter, not requiring a modulator, and lower switching frequency. The operation and robustness of MPUC7-ES1 and the introduced nonlinear FCS-MPCC technique are also illustrated through extensive simulation and experimental results.

Highlights

Increasing the percentage of inverter-based renewable energies in electric power systems seems inevitable to rein in the current global warming trend
Nondispatchable renewable energy resources, such as wind and solar, can participate in both active and reactive power imbalance mitigation. In this way, the employed conversion system will not be operational at maximum power point (MPP), which reduces the efficiency of the system
This system is powered through a controlled voltage source to study the operation of the introduced MPUC7-ES1 and controller

Summary

INTRODUCTION

Increasing the percentage of inverter-based renewable energies in electric power systems seems inevitable to rein in the current global warming trend. MPUC7-ES1 FCS-MPCC-BASED CONTROLLER As mentioned before, conventional PI-based ES1 controllers do not consider the nonlinearities of the MPUC7-ES1 converter and its output lowpass filter By employing these linear approaches, it is required to employ a modulation technique to generate switching signals indirectly [3], [12]. Ie∗s(k + 1) = 3ie∗s(k) − 3ie∗s(k − 1) + ie∗s(k − 2) (23) where ie∗s(k), ie∗s(k − 1), and ie∗s(k − 2) are the references for the current flowing through the MPUC7-ES1 output filter capacitor at the instants k, k − 1, and k − 2, respectively In this respect, the outer control loop is designed to generate the MPUC7-ES1 compensation voltage reference magnitude and phase angle. The computational burden and complexity of the proposed controller are minimized significantly

SIMULATION RESULTS

EXPERIMENTAL RESULTS

CONCLUSION