Analysis and minimization of input ripple current in PWM inverters for designing reliable fuel cell power systems

This paper presents the implementation of a technique to minimize the input ripple current in three-phase voltage-source pulse width modulated (PWM) inverters when supplying unbalanced/nonlinear loads. This is achieved without increasing the KVA ratings of the dc-link filter components. The results presented are particularly important for designers of fuel cell power systems. Inverter input ripple current has been reported to possibly degrade fuel cell performance and reduce operating life if ripple currents are not adequately controlled. Experimental results from a prototype are included to verify the findings from the analysis and simulation.