Avionic UPS - (Holdup)
Avionics ups are used to provide backup power to the aircraft's critical avionics systems in the event of a power failure. The Hold-Up module is used to keep the line voltage at the nominal level when a power failure occurs. The systems cannot notify the load of the power failure. Hold-up products are placed in front of the loads or directly in front of the main source in case of power failure that occurs during power supply changes in aircraft. Hold-up-ups can be used if the critical loads in the system are expected to work for a certain period of time in case of power failure. The hold-up ups system has an analog controller. The Hold-up capacitor charges while the system is operating normally. The input voltage is monitored by the analog controller. If the input voltage drops below the threshold voltage, then the analog controller activates the output voltage. The activation time, that is, the response time, is about 100us.