*2.2.3. Constraints imposed to the converter*

Regardless the topology of the converter selected, the constraints imposed by the PEM fuel cell should be respected that is, the minimum and maximum values of the voltage, the current and the power, which for the PEM Mark 1020 are listed in the Table 1 below.

former. Therefore, another group of DC -DC isolated converters utilizing more than one

Methodology of Designing Power Converters for Fuel Cell Based Systems: A Resonant Approach

http://dx.doi.org/10.5772/54674

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In switched-mode topologies, finite duration of the switching transitions will cause high peak pulse power dissipation in the devices, degradation of the converter efficiency and, also can lead to transistor damage during the turn-off transition. Employing load-line snubbers can reduce this problem. When using snubbers the stress of the switches are minimised, as shown in Figure 9. However, with the appearance of new power electronic converters based on softswitching technologies, [15,17,19,20-22,30], the reduction of switching losses and the continual improvement of power switches allow at being able to increase the switching frequency. In this type of converter the turning on and turning off of the converter switches appears when

the switch voltage or the switch current is zero, as shown in Figure 9 [23].

switch are identified: Push-pull, Half-bridge and Full-bridge converters.

**Figure 8.** DC-DC power converter family tree.


**Table 1.** Constraints imposed to the power system by PEM MARK 1020.
