Item – Theses Canada

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OCLC number
1433155206
Link(s) to full text
LAC copy
Author
Akbar, Muhammad Ali.
Title
Shunt Connected Power Conditioner with Energy Storage for a Hydrogen Fuel Cell System Supplying a DC Nanogrid.
Degree
M.A. Sc. -- Concordia University, 2019
Publisher
[Montreal, Québec] : Concordia University, 2019
Description
1 online resource
Abstract
DC power distribution systems (especially DC nanogrids) are becoming a great area of interest for researchers that can lead to better integration of distributed energy resources (DERs) and supplying local loads in a more efficient way compared to AC systems. As a power source for DC power distribution systems, the use of renewable energy source is increasing every day. When considering renewable energy sources, one can think of the most popular ones like photovoltaics (PV) and wind energy, but another environment-friendly power source that is gaining popularity is the hydrogen fuel cell (FC). DC nanogrids for Net-Zero Energy Homes (NZEHs) are expected to include a number of Distributed Energy Resources (DERs). FCs are an interesting choice as supplemental/dispatchable power sources because they can operate as co-generators supplying electricity and heat for NZEHs. The output voltage of the FC changes with the electric power demanded by the load (if the hydrogen injection in the FC is kept constant). Besides, if there is an instant change in the load current demand, it can also damage the FC. Therefore, to protect the FC and supply the load with a regulated voltage, a DC-DC converter is often employed as an interface for the FC. In such a case, load demand variations will lead to variations in the output power of the FC, which is at the maximum power point, when it is supplying a given amount of power at a given current. This thesis discusses the realization of a control scheme that enables a FC system to operate at the maximum power point by using an Energy Storage System (ESS) based on a super capacitor (SC) and another power electronics interface as a supporting unit. The output of the ESS is connected in shunt with the output of the FC system to the DC (load) bus. The ESS is current controlled to force the FC system to supply a constant current. In this way, the FC will supply an ideal, maximum power point, current even as the power demand by the electric load varies. Besides, the ESS can also provide the load with more power than the rated value of the FC system. Moreover, an additional control scheme is also implemented in the ESS to keep the voltage at the SC within safe and useful values. Finally, the proposed scheme is verified with hardware experiments. Experimental results with power electronics interfaces showing the voltage regulation in the DC (load) bus, FC current control and the regulation of SC voltage are presented. It is demonstrated that the FC can be operated at its maximum power point, using a SC-based ESS with injected current and SC voltage control loops.
Other link(s)
spectrum.library.concordia.ca
Subject
Hydrogen Fuel Cell as a power source, Maximum power point operation of Hydrogen Fuel Cell, Super Capacitor storage unit, Current and voltage control schemes for Super Capacitor Storage unit.