[en] Efficient operation results from a proper control strategy. In the operation and performance of a Proton Exchange Membrane Fuel Cell (PEMFC), the hydrogen gas flow rate is one of the most essential control parameter in addition to operating pressure, water management, temperature and humidity. This is because of the high cost and amount of energy are required to produce the purity hydrogen gas. In this paper, a Proportional Integral Derivative (PID) feedback control system is used to control the hydrogen flow rate. A strategy is adapted to balance the hydrogen use based on the loading requirements, especially during start-ups and sudden power demands. This system is implemented using National Instrument (NI) devices powered by the LabVIEW program. This is due to its simplicity and customization flexibility for measuring, processing and recording data. Designed structure allows the real-time implementation of a robust control law that is able to address the related nonlinearities and uncertainties without incurring a heavy computational load for the controller algorithm. While it facilitating a fast sampling rate according to the needs of the power system. Test results from the controller show that the new fuel control system provides good performance by reducing the amount of wasted hydrogen gas compared with that of the previous open loop system by 30 % to over 80 % saved by the varied load. This improvement is beneficial for any PEMFC that experiences fluctuating power demand, especially for vehicle applications. (author)

[en] A proton exchange membrane (PEM) fuel cells (FCs) with ultracapacitor (UC) and battery (BT) hybrid system has fast transient response compare to stand alone FCs. This hybrid system is promising candidates for environmentally friendly alternative energy sources. An energy management system design and control strategy was introduced in this study. The energy management strategy FC/ UC/ BT hybrid system model has been developed and the control strategy was programmed in the LabVIEWTM environment and implemented using National Instrument (NI) devices. The energy management strategy is able to manage the energy flow between the main power source (FCs) and auxiliary sources (UC and BT). To control the hybrid system and achieved proper performance, a controller circuit was developed with the three energy sources aligned in parallel to deliver the requested power. The developed model demonstrates the proportion power from the FC, UC and BT under various load demand. Experimental results demonstrate that FC/ UC/ BT hybrid system operated automatically with the varying load condition. The experimental results are presented; showing that the proposed strategy utilized the characteristic of both energy storage devices thus satisfies the load requirement. (author)

[en] This paper presented the transformation of a golf cart system powered lead acid battery into an environmental friendly hybrid vehicle. The design developed by using an advantage contributes by the uprising alternative power source candidate which is Proton Exchange Membrane Fuel Cell (PEMFC) and the maintenance free energy storage device, a supercapacitor (SC). The fuel cell (FC) stack was an in house manufactured with 450 W (36 V, 12.5 A) power, while the SC was from Maxwell Technologies (48 V, 165 F). This two power sources were controlled by the mechanical relay, meanwhile the reactant (hydrogen) are control by mass flow controller (MFC) both signaled by a National Instrument (NI) devices. The power management controller are programmed in the LabVIEW environment and then downloaded to the NI devices. The experimental result of the power trend was compared before and after the transformation with the same route to validate the effectiveness of the proposed power management strategy. The power management successfully controls the power sharing between power sources and satisfies the load transient. While the reactant control managed to vary the hydrogen mass flow rate feed according to the load demand in vehicular applications. (author)