AP16098
UPS Main Control
Main Control Principle
Application Note
10
V1.0, 2007-03
The microcontroller is also in charge of the synchronization control of all modules of this
UPS system as well as the inverter feedback control. The line voltage zero-crossing signal
is captured by the microcontroller to synchronize the input voltage/phase with the output
voltage/phase. The ON/OFF control signals for DC-bus relay and bypass relay along with
TRIAC control signal are both produced by the microcontroller.
The display control board is designed based on an Infineon 8-bit microcontroller XC866
which needs to communicate with the microcontroller on the main control board for data
transfer and receiving. Two necessary signals RxD and TxD are offered by the
microcontroller to be connected with XC866 for implementing display of states, operation
and errors information.