Techno-economic analysis of contingency reserve allocation scheme for combined UHV DC and AC receiving-end power system

In a UHV DC and AC combined system the UHVDC's blocking fault becomes the most serious load balance contingency of the receiving end power system due to its large capacity. The amount of contingency reserve thus is largely increased. This paper proposes three distinct schemes for allocating contingency reserve to cover the power shortage caused by UHVDC's blocking fault, and compares the economic cost of these schemes. An operation simulation method using a unit commitment technique is proposed for evaluating the operation costs associated with increasing contingency reserve. A real case study for a Jiangsu Province power system in China is presented to demonstrate that the best scheme is to share the contingency reserve with neighborhood power systems through the transmission capacity of UHVAC lines.