Investigating the Impact of Methanol Concentration and Implementation of a Coefficient Diagram-Based Control System for Direct Methanol Fuel Cell Operation

The impact of methanol concentration on direct methanol fuel cell (DMFC) of 45 cm2 zones of activity was experimentally studied with serpentine channel field design. The performance of the DMFC was analyzed and the optimum methanol concentration was determined with a polarization curve. A recently suggested Coefficient Diagram derived from PI Controller (CD-PIC) was used to run the model-based DMFC in a closed loop with the manipulated variable as methanol concentration. The CD-PIC design is simple and efficient compared to the Bode Diagram-based controller design. It is also used to test the performance and robustness of the system apart from the stability. A recently suggested PI Controller that relies on a Coefficient Schematic is employed in DMFC operation. The progress of the proposed CD-PIC is evaluated under load abandonment circumstances and set point monitoring. Set point tracking and load rejection tests are carried out with step changes at different operating points. The controller execution is evaluated in ways of controller progress measuring (CPM) indices. The suggested performance metrics for the proposed CD-PIC indicate that it yields better performance for servo problems and regulatory problems which support the supremacy of CD-PIC. The robustness of the CD-PIC is also analyzed. From the CPM indices, it is concluded that the recently created CD-PIC for DMFC is found as highly robust.