Droop Control for Parallel-Connected Three-Phase UPS Units with Different Ratings

Ramadan, Mohamed M.; Koutb, Prof. Magdy A.

doi:10.21608/mjeer.2020.69010

	Droop Control for Parallel-Connected Three-Phase UPS Units with Different Ratings
Menoufia Journal of Electronic Engineering Research
Article 2, Volume 29, Issue 1, January 2020, Page 13-20 PDF (1.94 MB)
Document Type: Original Article
DOI: 10.21608/mjeer.2020.69010
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Authors
Mohamed M. Ramadan; Prof. Magdy A. Koutb
Department of Industrial Electronics and Control Eng., Faculty of Electronic Eng., Menoufia University, Egypt
Abstract
The main objective of this paper is to achieve synchronization and power sharing between different ratings three-phase Uninterruptible power supply (UPS) units. A droop control scheme is presented in such a way that a discrete PI-controller is applied. The PI-controller produces a suitable control signal to sinusoidal pulse width modulation (SPWM) circuit. The SPWM produces suitable trigger pulses to the inverter gate. The validity of the proposed control scheme is illustrated through MATLAB simulation with two different ratings three-phase UPS units. The simulation results prove that it possible to share the total load among the different rating units in proportion with their rated values in the presence of load interruption.
Keywords
Uninterruptible Power Supply (UPS); Parallel Operation; Power Sharing; Droop Control; Discrete PI-Controller; Sinusoidal Pulse Width Modulation (SPWM)


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