Phase Angle Analysis for Three-Phase PWM-Switched Autotransformer Voltage-Sag Compensator

Dynamic voltage restorer (DVR) is among the other voltage sag compensators introduced to mitigate voltage sag occurrences. DVR requires energy storage but is inadequate for compensating deep and long-duration voltage sags. AC–AC sag compensators, next introduced, need no storage device, being capable of what DVR was not. Dropped AC voltage needs AC–AC converter to become regulated AC voltage. This paper presents two tasks. First, a new three-phase voltage sag detection controller that is based on phase-angle analysis is developed. This technique is able to detect and compensate three-phase sag the moment it occurs. Beside fast detection response, it is simple to implement and involves less mathematical computation. Second, a three-phase topology of voltage sag compensator is introduced. The advantage of this detection technique is the detection time. It is capable of detecting and compensating voltage sag the moment sag occurs, without delay. Its effectiveness and capability were verified via MATLAB/Simulink simulation while the proposed detection technique was further investigated through a controller developed using TMS320F2812 DSP.