Power Transfer Devices, Methods, and Systems with Crowbar Switch Shunting Energy-Transfer Reactance

Abstract

The present application discloses methods, circuits and systems for power conversion, using a universal multiport architecture. When a transient appears on the power input (which can be, for example, polyphase AC), the input and output switches are opened, and a crowbar switch shunts the inductance which is used for energy transfer. This prevents this inductance from creating an overvoltage when it is disconnected from outside lines.

1 - 76 . (canceled) 
     
     
         77 . A method for operating a power conversion circuit, comprising the steps of repeatedly, at various times:
 driving current into the parallel combination of an inductor and a capacitor, and immediately thereafter temporarily disconnecting said parallel combination from external connections, to thereby transfer some energy from said inductor to said capacitor;   wherein said driving step is performed in opposite senses and various times, and wherein said disconnecting step is performed for both senses of said driving step;   repeatedly extracting energy from said parallel combination, to thereby perform power conversion; and   under at least some conditions, disconnecting said rparallel combination from both said power input and said power output, while also dumping energy from said parallel combination through a switch+resistor combination which shunts said parallel combination.   
     
     
         78 . The method of  claim 77 , wherein said inductor is implemented by a transformer. 
     
     
         79 . The method of  claim 77 , wherein said driving step is performed by a full-bridge array of input switches. 
     
     
         80 . The method of  claim 77 , wherein said driving step is performed by a full-bridge array of bidirectional switches. 
     
     
         81 . The method of  claim 77 , wherein said extracting step is performed by a full-bridge array of bidirectional switches. 
     
     
         82 . A power conversion circuit, comprising:
 an input switch array which repeatedly, at various times, drives current into the parallel combination of an inductor and a capacitor, and immediately thereafter temporarily disconnects from said parallel combination;   wherein said action of driving current is performed in opposite senses at various times, and wherein said disconnecting operation is performed for both said senses;   an output switch array which repeatedly, at various times, extracts energy from said parallel combination, to thereby perform power conversion, and immediately thereafter temporarily disconnects from said parallel combination; and   a link switch which is connected across said parallel combination, in a crowbar configuration which includes resistance, to dissipate energy stored in said parallel combination, at times when both said said input and said output switch arrays are disconnected from said parallel combination;   whereby, at times when said input and output switch arrays are disconnected from said parallel combination, and said link switch is off, energy is transferred between said inductor and said capacitor, to thereby change the voltage across said parallel combination.   
     
     
         83 . The converter of  claim 82 , wherein said input stage comprises a full-bridge array of bidirectional switches. 
     
     
         84 . The converter of  claim 82 , wherein said wherein said input and output stages each comprise a full-bridge array of bidirectional switches, and are symmetrically connected to said energy-transfer reactance. 
     
     
         85 . The converter of  claim 82 , wherein said stages each selectably connect said parallel combination to a low-impedance voltage source/sink. 
     
     
         86 . The converter of  claim 82 , wherein said inductance comprises a transformer.