Multifunction hybrid intelligent universal transformer

Abstract

A multifunction hybrid intelligent universal transformer includes a conventional transformer coupled with power electronics on the secondary side to enhance the functionality of power conversion. The universal transformer includes features for overcoming the deficiencies associated with conventional transformers, including voltage sag compensation, instantaneous voltage regulation, outage compensation, capacitor switching protection, harmonic compensation, single-phasing protection, DC output, and variable frequency output.

1 . A power conversion device, comprising: 
 a transformer having a number of primary windings adapted to be coupled to a three-phase power source and a number of secondary Δ-Δ and Δ-Y connections;    a first switched inverter coupled to the Δ-Δ secondary connection; and    a second switched inverter coupled to the Δ-Y secondary connection and to the first switched inverter for providing a harmonically compensated waveform.    
     
     
         2 . The device of  claim 1 , further comprising: 
 AC/DC converter blocks coupled to the secondary Δ-Δ and Δ-Y connections for converting Alternating Current (AC) waveforms into Direct Current (DC) waveforms.    
     
     
         3 . The device of  claim 2 , wherein the AC/DC converter block is a diode bridge.  
     
     
         4 . The device of  claim 1 , further comprising: 
 an energy storage device coupled to the input of at least one of the first and second switched inverters.    
     
     
         5 . The device of  claim 1 , further comprising: 
 a filter coupled to the output of at least one of the first and second switched inverters.    
     
     
         6 . A power conversion device, comprising: 
 a transformer adapted to be coupled to a power source;    power electronics coupled to the transformer for transforming the power source into a desired waveform; and    an energy storage device coupled to the transformer and the power electronics for mitigating interruptions in the power source.    
     
     
         7 . The device of  claim 6 , further comprising: 
 a converter coupled to the transformer for converting the power source from Alternating Current (AC) waveforms to Direct Current (DC) waveforms.    
     
     
         8 . The device of  claim 6 , wherein the power electronics include an actively switched inverter for providing a desired output waveform.  
     
     
         9 . The device of  claim 8 , wherein the switched inverter is controlled by pulse width modulation.  
     
     
         10 . The device of  claim 6 , wherein the converter is a switched full-bridge converter.  
     
     
         11 . The device of  claim 6 , further comprising: 
 a filter coupled to the power electronics for smoothing the output waveform.