Impact of Thermal Reactor Radiation on Power Converter Circuit Performance

The increase in demand for renewable energy sources has driven several innovations in materials and electronics worldwide. Many of these sources, chiefly solar, operate off direct current (DC). One disadvantage of DC over alternating current (AC) is the inability to use transformers for voltage or current manipulations. While most small-scale electronics make use of DC voltages of 5 Volts or less, some applications require higher electric potential. This is especially true when integrating DC-generated renewables onto a grid designed for AC. Solid-state circuits, aptly named boost converters, are the DC analogous to step-up transformers where a higher potential is established at the expense of reduced current.One application for boost converters is their use in creating a bias voltage for radiation detectors. A silicon photomultiplier (SiPM), when attached to a scintillating material, has replaced the need for large photomultiplier tubes, which has decreased the size of radiation detectors significantly. Similar to photomultiplier tubes, SiPMs require a high-voltage bias for operation. Often these detectors are powered by 5 Volt batteries, but the inclusion of a boost converter allows for a potential of nearly 100 Volts.By nature, a radiation detector is subject to potentially damaging ionizing events. The boost converter circuit specifically, which makes use of a metal-oxide-semiconductor field effect transistor (MOSFET), is highly susceptible to radiation damage. This summary explores the ongoing efforts to explore the performance of the boost converter circuit under high gamma and neutron fluxes to design resilient radiation monitoring electronics. The live monitoring of a boost converter circuit placed within the Purdue University reactor (PUR-1) has given insight into the upper limits of radiation damage for boost converters.