Comparison and selection of overlay extra high voltage in North West China power network

The choice of proper overlay extra high voltage is an urgent and difficult problem faced by planning engineers in the Northwest Electric Power Administration (NWEPA). In this paper, a brief presentation of the North West China Power Network (NWCPN) is offered. Next, a comparison both in technical and economic terms is described. In the author's opinion: 500 kV AC is not a good solution; 750 kV is an ideal alternative in theory, but it meets many barriers in practice; while 500 kV MTDC (multi-terminal DC) may be chosen as a feasible solution.<
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