Increase Resilience Of Uninterruptible Power Supply Against Network Disturbance

Serious problems can be posed by exceeding the allowable limit of overvoltage in AC circuits, which is a significant issue. A simplified configuration is proposed in this paper to address sudden voltage surges and prevent voltage exceeding permissible thresholds for operating single-phase (UPS) devices after reviewing previous researches that relies on effective protection against transient surge and protection from overvoltage. This enhances the resiliency of UPS devices to various voltage fluctuations in the electrical grid. The proposed approach is split into two parts, with the first one, a back-to-back MOSFET is incorporated in series with the load to protect it by cutting off the current from the load during overvoltage occurrences. The second part involves a back-to-back MOSFET in series with a snubber circuit, connected in parallel with the load to operate as an active snubber circuit during transient surges. Several electrical grid disturbances are analyzed in the study using MATLAB. The simulation outcomes prove that the new configuration is effective in managing sudden voltage surges, constrains their magnitude, and disconnects the voltage from the UPS if it persists in exceeding the permissible limits. Additionally, the results from the overvoltage protection experiment indicate that the suggested control circuit effectively isolates the load from the circuit when the utility voltage surpasses the safe range for over 100ms.