Three-Phase PWM-Switched Autotransformer Voltage-Sag Compensator Based on Phase Angle Analysis

  • Mansor, Muhamad (Dept. of Electrical Power Engineering, Universiti Tenaga Nasional) ;
  • Rahim, Nasrudin Abd. (UM Power Energy Dedicated Advanced Centre (UMPEDAC), University of Malaya)
  • Received : 2010.10.14
  • Published : 2011.11.20


Many voltage sag compensators have been introduced, including the traditional dynamic voltage restorer (DVR), which requires an energy storage device but is inadequate for compensating deep and long-duration voltage sags. The AC-AC sag compensators introduced next do not require a storage device and they are capable of compensating voltage sags. This type of compensator needs an AC-AC converter to regulate the output voltage. Presented in this paper is a three-phase PWM-switched autotransformer voltage sag compensator based on an AC-AC converter that uses a proposed detection technique and PWM voltage control as a controller. Its effectiveness and capability in instantly detecting and compensating voltage sags were verified via MATLAB/Simulink simulations and further investigated through a laboratory prototype developed with a TMS320F2812 DSP as the main controller.


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