@article{CRSIJ26000368,
                  author = {Ndifreke Akpan, Agorodi Dioni, Baruch Ekanem, Mbet-obong Akpan},
                  title = {Evaluation of Dc-Link Voltage Control Strategies and Their Impact on Three-Phase Output Sinusoids},
                  journal = {Cosmo Research and Science International Journal},
                  year = {2026},
                  volume = {2},
                  number = {2},
                  pages = {122-133},
                  issn = {3108-1584},
                  url = {https://cosmorsij.com/published/CRSIJ26000368.pdf},
                  abstract = {One of the main drivers of the AC-side waveform distortion in voltage source inverters (VSIs) is the DC-link voltage oscillations, especially when they operate under fluctuating power situations such as in renewable energy systems. In this work, different control strategies for regulating the DC-link voltage and their effects on the quality of the three-phase output waveforms are analysed using MATLAB simulations. A comparison of the conventional proportional–integral (PI) controller with a nonlinear energy-based control (EBC) technique under the same operating conditions, including a low-frequency DC-link disturbance of 50 V at 10 Hz, is shown. The simulation results reveal that the ripple of the DC-link voltage of the system regulated by PI is about a 0.112 V peak-to-peak value. The maximum voltage inaccuracy is 0.056V (±6.14 %), which leads to a great distortion at the AC output. The energy-based controller limits the DC-link ripple to roughly 0.024 V with a maximum voltage error of 0.012 V, which results in a 74.3 % reduction in RMS voltage error. The examination of the AC-side distortion also shows the benefits: the peak distortion index is lowered from 0.8 pu (PI control) to 0.018 pu (EBC) with an improvement of 83.6%, and the average distortion is decreased by 89.2 %. The presented results validate the success of the nonlinear energy-based DC-link regulation to suppress propagation of oscillations on the DC side to AC currents. Therefore, it significantly increases the three-phase sinusoidal quality and the overall power quality. The results also show that it is more successful to regulate the energy of the DC-link than to control only the voltage error in an effort to keep good-quality three-phase sinusoidal outputs.},
                  keywords = {Voltage Source Inverter, DC-Link Voltage Control, AC-Side Distortion, Energy-Based Control, Proportional–Integral (PI) Control},
                  month = {September}
        }