A feedback based load shaping strategy for fuel utilization control in SOFC systems

Proceedings of the 2010 American Control Conference

2010

Self Cite

In this paper we design robust control strategies for a hybrid solid oxide fuel cell ultra-capacitor system. Fuel cell control is established by using an invariant property of fuel utilization within an input-shaping framework. Two control strategies are developed. The first design uses a nonlinear control approach for which we prove the stability of the closedloop system in presence of system uncertainties. The second uses a standard H ∞ robust control approach. Both strategies enforce the control of State of Charge (SOC) of the ultra-capacitor to a desired level. A hardware-in-the-loop test-stand is developed and experimental results are provided.

Section: Open-loop Control Of Umentioning

confidence: 99%

“…A system description and the uncontrolled response of U to transient current are presented in section II. Steady-state relation for this system, derived in [4], is used for open-loop control of U in section III. Feedback based input shaping of fuel cell current is presented in section IV.…”

Section: Introductionmentioning

confidence: 99%

Robust nonlinear control of fuel cell ultra-capacitor hybrid system

Allag

Proceedings of the 2010 American Control Conference

2010

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“…Based on the molar balance equations and the rate of electrochemical reaction, a steady-state relationship of can be obtained as in (2), where is a known fraction of the anode exhaust flow that is recirculated, is the number of cells in series, is the is the fuel cell current. The derivation is shown in our prior work [29], [18] (2)…”

Section: B Current Regulationmentioning

confidence: 99%

“…A strategy for attenuating transient fluctuations in fuel utilization, developed in our prior work [18], [19], will be outlined in this section. For an SOFC system such as in Fig.…”

Section: B Current Regulationmentioning

confidence: 99%

See 1 more Smart Citation

Adaptive Control of a Solid Oxide Fuel Cell Ultra-Capacitor Hybrid System

IEEE Trans. Contr. Syst. Technol.

Snyder

2013

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Solid oxide fuel cells (SOFCs) offer a number of advantages beyond those of most other fuel cells. However, like other fuel cells, rapid load following is difficult, and can lead to fuel starvation and consequently fuel cell damage. Mitigating fuel starvation and improving load following capabilities are conflicting control objectives. However, the issue can be addressed by the hybridization of the system with an energy storage device. In this paper, a steady-state property of the SOFC, combined with a current regulation strategy, is used to manage transient fuel utilization and thereby address fuel starvation. Meanwhile, an overall system strategy is employed to manage energy sharing in the hybrid system for load following as well as for maintaining the state-of-charge of the energy storage device. This work presents an adaptive control algorithm that uses online parameter estimation to update the controller. The control design is validated on a hardware-in-the-loop setup and experimental results are provided.Index Terms-Adaptive control, fuel utilization, hybrid energy, robust control, solid oxide fuel cell (SOFC), transient, ultra-capacitor.

Adaptive control of a solid oxide fuel cell ultra-capacitor hybrid system

Proceedings of the 2011 American Control Conference

Snyder

2011

Self Cite

Solid oxide fuel cells (SOFCs) offer a number of advantages beyond those of most other fuel cells. However, like other fuel cells, rapid load following is difficult, and can lead to fuel starvation and consequently fuel cell damage. Mitigating fuel starvation and improving load following capabilities are conflicting control objectives. However, the issue can be addressed by the hybridization of the system with an energy storage device. A steady-state utilization property, combined with a current regulation strategy, is used to manage transient fuel utilization. Meanwhile, an overall system strategy is employed to manage energy sharing in the hybrid system for load following as well as for maintaining the state-of-charge of the energy storage device. This work presents an adaptive strategy which updates the controller based on current parameter estimates. The control design is validated on a hardware-inthe-loop setup and experimental results are provided.