Energy Management of a Fuel-Cell Serial–Parallel Hybrid System

Abstract

In this work, a serial-parallel hybrid (SPH) power system formed by a Fuel Cell (FC), an Auxiliary Storage Device (ASD) and the current-controlled dc-dc converters responsible for the power management are realized by using the Digital Signal Controller (DSC) TMS32F28335. The main energy management goal is to transfer energy from the sources (FC or ASD) to the load while ensuring dc bus voltage regulation and high power conversion efficiency. In addition, a safe and reliable operation of the system has to be achieved. The selected converter and its controller features are: non-inverting voltage step up and step down, high efficiency, input and output currents regulation an low ripple values, and the ability to change from input to output current regulation loop, suddenly and smoothly, and vice versa. All these features allow it to be positioned in different FC system localizations and simplifies the design of the master control. Simulation and experimental results have been validated on a 48-V, 1200-W dc bus.

Supercapacitor Sizing for Fast Power Dips in a Hybrid Supercapacitor—PEM Fuel Cell System

“…It is worth noting that the value of R i used in (7) is the value reported in Table I, experimentally identified from the supercapacitor frequency response. This value was used here for a meaningful comparison between the estimated maximum current and simulation and measurement results.…”

“…The main reason for this is related to the slow dynamics of FCs, which are not able to effectively deal with fast load changes. In a hybrid system, the FC cooperates with other sources (such as batteries or supercapacitors) thanks to power converters supervised by a master control system [7], [8]. In this way, a fast dynamic response of the whole system is achieved, while the FC operates in almost stationary conditions even in the case of sudden load changes, such as strong accelerations and regenerative braking in powertrain applications.…”

Energy management strategies for a fuel-cell/battery hybrid power system

“…The EMS system is needed to ensure different requirements as low hydrogen consumption, high efficiency and long life span of the hybrid source. 25,26 This can be achieved by controlling the output power of each source according to their limits and the load power. In this article, three state-of-the-art EMSs are used which are RFL strategy, OC as offline strategies and the FS strategy as an online one.…”

A Bidirectional Versatile Buck–Boost Converter Driver for Electric Vehicle Applications

“…In addition, the introduction of an RC damping network in parallel with the intermediate capacitor, combined with the coupled-inductors, eliminates the right half-plane zero that limits the closed-loop bandwidth of the step-up converters [ 28 ]. All the advantages mentioned above have allowed its use in different fuel cell hybrid power systems [ 32 , 33 , 34 ] and deepen on various digital current control techniques [ 35 , 36 , 37 ].…”