Patent ID: 9685878
Date: 2017-06-20
CPC Classifications: H02M,Y02E

Claim:
1. A power electronic interface system for connecting a plurality of alternating current transmission lines by one or more direct current transmission lines comprising: a first dc-link converter adapted to be connected to an alternating current transmission line, said converter increases the frequency of the alternating current received from an alternating current transmission line; a frequency transformer connected to said converter, said frequency transformer increases the voltage of the alternating current received from said converter; a modular multilevel converter that receives alternating current from said frequency transformer, said modular multilevel converter converts the alternating current received from said frequency transformer to direct current for transmission on a direct current transmission line; a second dc-link converter comprising a modular multilevel inverter adapted to receive direct current from a direct current transmission line, said modular multilevel converter converts the direct current received from a direct current transmission line to alternating current; a frequency transformer connected to said modular multilevel converter, said frequency transformer decreases the voltage of the alternating current received from said modular multilevel converter; and a converter connected to said frequency transformer, said converter decrease the frequency of the alternating current received from said frequency transformer for transmission to an alternating current transmission line.