Author: Wong, Ming-kwan Thomas
Title: Parallel power supply using droop method with output voltage feedback to improve load regulation
Degree: M.Sc.
Year: 2002
Subject: Hong Kong Polytechnic University -- Dissertations
Electric power distribution
Electric power supplies to apparatus
Voltage regulators
Electric power systems -- Load dispatching
Department: Multi-disciplinary Studies
Department of Electronic Engineering
Pages: viii, 101 leaves : ill. (some col.) ; 30 cm
Language: English
Abstract: The parallel power supplies using the droop method for load current sharing are infamous for poor load regulation. It was shown in this study that the load regulation of a parallel power supply using the droop method for load current sharing could be improved by using output voltage feedback. In this study a parallel power supply consisting of two identical flyback converters was used to demonstrate the effects of using output voltage feedback. The output voltage of the parallel power supply was compared to an external reference voltage. The voltage error was amplified and feedback to compensate for the droop voltage and other losses so as to improve load regulation. Tight load regulation might be achieved by increasing the gain of the voltage error amplifier. The current error between converter modules was not affected by using output voltage feedback. However the transient responses were affected by using output voltage feedback. It was further found that the power supply responded faster to load current changes while the transient voltage caused by load current changes was lower after output voltage feedback was adopted. It was shown that at the same load current level the loop transfer function of the parallel power supply with output voltage feedback was not affected by the number of converters in the system. Therefore the parallel power supply using the droop method for load current sharing with output voltage feedback is a modular approach. It was further shown that the resistance of the loading resistor affected the loop transfer function of the parallel power supply. Therefore stability analysis at different load current levels were needed to ensure the closed-loop system would be stable. A discussion on the effect of output voltage feedback on the system reliability was also included.
Rights: All rights reserved
Access: restricted access

Files in This Item:
File Description SizeFormat 
b16681721.pdfFor All Users (off-campus access for PolyU Staff & Students only)3.24 MBAdobe PDFView/Open


Copyright Undertaking

As a bona fide Library user, I declare that:

  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.

By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.

Show full item record

Please use this identifier to cite or link to this item: https://theses.lib.polyu.edu.hk/handle/200/5264