Detection of instability and adaptive compensation of digitally controlled switched-mode power supplies

This paper demonstrates the feasibility of detecting an onset of instability by monitoring the pattern of the output voltage error signal, and adaptively changing the compensator parameters in a digitally controlled switched-mode power supply. The techniques are verified on an experimental 90 W, 50 V-to-15 V forward converter where an abrupt change in operating conditions that leads to instability is emulated by removing the input filter damping. It is shown that the system can regain stability and return to regulation. The proposed techniques have potential applications in decentralized active stability control of power management and distribution systems typical for aerospace applications