arXiv:2611.09276v1 Announce Type: new Abstract: Single-isolation-stage solid-state transformers with balancing circuits eliminate an additional downstream dc--dc conversion stage. However, the remaining isolated converters must directly accommodate a wide output-voltage range. This paper investigates variable dc-link voltage operation of a single-isolation-stage multioutput SST to ease this requirement. Coordinated cascaded H-bridge modulation and embedded four-switch balancing circuits support intentionally unequal submodule dc-link voltages, allowing the isolated-converter input voltages to be adjusted according to the output requirements. The achievable voltage range is determined by relating the required balancing power to the BC transfer capability within the available CHB switching windows, subject to modulation and peak and rms current limits. The analysis quantifies the range extension provided by BC operation beyond modulation alone. For a single-phase-shift dual-active-bridge converter, input-voltage following within this range reduces the calculated peak current and extends the ideal zero-voltage-switching region compared with fixed input. Experiments on a six-submodule SST prototype demonstrate unequal dc-link voltage operation and inter-submodule power exchange. Experiments result on DAB demonstrate reduced current stress and improved efficiency with voltage following.