Mission Results Analysis of High-Voltage Technology Demonstration Satellite HORYU-II

In 2012, the high-voltage technology demonstration satellite HORYU-II which is a nanosatellite (30 cm
³
, 7 kg) was launched into polar earth orbit. It is known that high-voltage power generation above 200 V in low earth orbit induces discharging. The main mission of HORYU-II was to achieve high-voltage (more than 300 V) generation without discharge in space orbit, and it was successful. After the initial operation, HORYU-II malfunctioned due to the single event latch-up, and could not continue mission operation. On December 22, 2014, HORYU-II was revived and restarted mission operations until HORYU-II malfunctioned again (March 18, 2015). We performed three types of missions that were high-voltage generation modes, nominal TJ array discharge experiment modes, and film TJ array discharge experiment modes. Even if the satellite spent two years in orbit, HORYU-II could still generate around 350 V and the discharge rate on a nominal TJ array showed little change.