Often scientific instruments on exploratory satellites are used to collect cosmic particles. These instruments such as the Faraday cup require a high voltage regulated power source. On the proposed solar probe satellite there will be instruments which will collect cosmic particles close to the sun. Naturally temperature effects on the voltage regulator are a concern. Specifically power dissipation within the regulator must stay within stringent guidelines. The high voltage regulator circuit is a resonant flyback topology with a dissipative series switch whose on resistance controls the output voltage. The extreme temperatures in space will change the inductance of the flyback transformer which will affect the output voltage.State space analysis techniques are used to determine how the value of the transformer inductance and capacitance in the flyback converter affects the output voltage and consequently the power dissipated by the transformer and the switch. The accuracy of the analysis is verified by comparing results with those obtained from an experimental circuit. The results can then be used to help the designer chose nominal capacitance and inductance values that will work over the temperature range of interest.