Computerized DC (battery) load flow calculations

The key to properly sizing cables, overcurrent devices, and batteries is correctly calculating load current. The load current for constant-power devices increases as voltage decreases. The opposite is true for constant-resistive devices. If the effects of voltage are neglected, the designer can over-design circuits for constant-resistance loads and under-design circuits for constant-power loads. The authors describe how computerized techniques have existed for some time for AC system analysis and how these techniques can easily be adapted for DC analysis. This will allow designers to quickly perform the what-if games required to strike a balance between conservative design and costs.