Voltage stability assessment method for multi-infeed AC/DC hybrid power system

Abstract

The invention discloses a voltage stability assessment method for a multi-infeed AC/DC hybrid power system. On the basis of a multi-infeed effective short circuit ratio considering shunt capacitor compensation, a reactive power conversion factor is adopted for describing an influence degree on voltage of a DC system by a shunt capacitor compensation point in an AC system, a conversion method is adopted for acquiring reactive power influence quantity on the DC system by a shunt capacitor connected with each compensation point in the AC system, reactive power influence quantities on the DC system by all shunt capacitor compensation points in the system are accumulated, and bad influences on voltage stability of the DC system by whole system shunt compensation are acquired. According to the whole system reactive power influence quantities, the effective short circuit ratio is acquired, influences included in shunt capacitor compensation are further acquired, and stability of the power system is assessed according to the effective short circuit ratio. Compared with the current AC/DC hybrid power system voltage stability assessment method on the basis of the multi-infeed effective short circuit ratio, the method provided by the invention has high accuracy, and provides a basis for planning and operation of a multi-DC infeed power grid system.

Description

technical field [0001] The invention belongs to the field of power system planning, and more specifically relates to a method for evaluating voltage stability of a multi-infeed AC / DC hybrid power system. Background technique [0002] With the multi-circuit UHV DC project put into operation, the East China Power Grid and the Southern Power Grid in my country have formed a multi-DC feed-in receiving end system, with dense DC landing points and large transmission capacity, which has brought great benefits to the safe and stable operation of the AC-DC hybrid power system. A new challenge, how to accurately judge the voltage stability of the multi-infeed system is very important. [0003] In the planning and operation of DC lines, multi-infeed effective short-circuit ratio indicators are usually introduced to measure the strength of the interaction between DC and DC in the AC-DC hybrid power system and the strength of the reactive power and voltage support ability of the grid to t...

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Problems solved by technology

[0007] In view of the above defects or improvement needs of the prior art, the present invention provides a voltage stability evaluation method for a multi-infeed AC / DC hybrid power system, the purpose of which is to solve the problem that the existing multi-infeed effective short-circuit ratio index cannot accurately account for the system The shunt capacitor compensation in the current AC / DC hybrid power system voltage stability assessment method based on the multi-infeed effective short-circuit ratio index is inaccurate

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