Control of fuel cell/supercapacitors hybrid power sources

Abstract

This paper presents a control strategy for employing PEM fuel cell, known as slow dynamic device, as main power source and supercapacitors, known as high dynamic storage elements, as auxiliary power source for dc distributed system. The main point is to regulate the dc bus, and the important constraint is to avoid speedy operation of fuel cell current. Therefore, fuel cell is simply operating in almost steady state conditions in order to ensure a good synchronization between fuel (hydrogen and oxygen) flow and fuel cell current and to lessen mechanical stresses. The proposed control is based, first, on the regulation of the dc bus voltage through the control of the power delivered by the supercapacitors, and second, on the control of the supercapacitor voltage by the operating of the fuel cell. To validate control algorithms, hardware system is realized by analogical current loops and digital voltage loops (dSPACE). Experimental results, with a ZSW PEM 500 W, 12.5 V, 40 A fuel cell and a SAFT 292 F, 30 V, 400 A supercapacitor module for a 42 V dc distributed network, confirm system operations.

A comparative study and parameterization of supercapacitor electrical models applied to hybrid electric vehicles

“…En el diseño del sistema, se ha considerado, un filtro paso bajo en el orden de los mHz para la referencia de potencia de la pila de hidrogeno, en concreto flow=300mHz. Para la selección de este filtro, hay que considerar la necesidad de evitar sobrepasar la pendiente de corriente que una pila de combustible real es capaz de proporcionar, que es del orden de los 4A/s [161]. Las curvas de respuesta temporal que se obtienen de la simulación del sistema completo se muestran en la Figura 7.33.…”

Energy management analysis and design for a 5 kW PEMFC distributed power system

“…For these reasons, an auxiliary energy storage device is needed to compensate the transient power of the load. Thus, the fuel cell only need to export the slowly varying component of the load power, a more reliable operation condition can be achieved for the fuel cell [1][2][3][4][5][6][7][8][9][10].…”

“…In reference [7], a battery or super capacitor is paralleled with the fuel cell or the output of the frontended DC/DC converter in fuel cell power system as the energy buffer,. But the battery may also suffer the damage caused by the load sharp transition.…”