Adaptive power-voltage droop control method and system for direct current transmission system

Abstract

The invention discloses an adaptive power-voltage droop control method and system of a DC power transmission system, belonging to the field of power transmission and distribution of power systems. Including: building the upper limit loop, lower limit loop and additional loop; the output power of the upper limit loop is multiplied by the adaptive power-voltage slope coefficient to obtain the first product, and the output power of the lower limit loop is multiplied by the adaptive power-voltage slope coefficient , to obtain the second product; add the first product and the second product, and the sum value is used as the output voltage of the first control branch, and the output voltage of the additional loop is directly used as the output voltage of the second control branch; when the second converter outputs active power The power is greater than or equal to the action power of the hysteresis comparator, and the output of the second control branch is taken as ΔU dc ; When the active power output by the second converter is less than or equal to the return power of the hysteresis comparator, the output of the first control branch is taken as ΔU dc ; the ΔU dc Sum the command value of the DC voltage of the high-voltage valve group under the rated working condition to obtain the DC voltage of the high-voltage valve group.

Description

technical field [0001] The invention belongs to the field of power transmission and distribution of power systems, and more specifically relates to an adaptive power-voltage droop control method and system for a direct current transmission system. Background technique [0002] Under the current background of prominent energy security issues and severe environmental pollution, vigorously developing new energy sources such as wind power and realizing energy transformation is the key to smog control and environmental protection, and is the development direction of China and the world. The DC collection and transmission of new energy clusters can improve power transmission efficiency and grid flexibility, and is an important part of the future AC-DC hybrid grid form. [0003] The layered access-hybrid cascade DC transmission system can give full play to the technical advantages of conventional DC transmission and flexible DC transmission, and realize long-distance transmission o...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the defects and improvement needs of the prior art, the present invention provides an adaptive power-voltage droop control method and system for a direct current transmission system, the purpose of which is to effectively solve problems such as bridge arm overcurrent and reactive power surplus in converter stations, Guarantee the stable operation of the system in the case of power fluctuations

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