Power coordination control method and apparatus applicable to LCC type direct current power transmission system

Abstract

The invention provides a power coordination control method and apparatus applicable to an LCC type direct current power transmission system. Imbalance reactive power of an alternating current and direct current system is collected according to a self-defined time period, and whether the imbalance reactive power value is zero or not is judged; if so, a reactive compensation apparatus does not act; or otherwise, difference between the imbalance reactive power and reactive compensation amount of a dynamic reactive compensation apparatus is calculated, then comparison with the capacity of the dynamic reactive compensation apparatus is performed, and whether the difference value reaches the upper and lower limit values of capacity of the dynamic reactive compensation apparatus or not is judged; if not, the imbalance reactive power is returned to zero and the calculation is completed; or otherwise, an input / removing instruction is sent to an alternating current filter through a switching logic rule; and the capacity of the dynamic reactive compensation apparatus is re-configured according to the change conditions of imbalance reactive power and the switching of the alternating current filter after the instruction is sent out. By virtue of the power coordination control method and apparatus, quick reactive control is realized, voltage and current are maintained to be stable and balanced, and power transmission stability is ensured.

Description

technical field [0001] The invention relates to the field of LCC direct current transmission systems, and specifically proposes a power coordination control method and device suitable for LCC direct current transmission systems. Background technique [0002] Traditional high-voltage direct current transmission, that is, the high-voltage direct current (Line Commutated Converter High Voltage Direct Current, LCC-HVDC) transmission system based on grid commutation converters, has the advantages of large transmission capacity, low cost, and fast and controllable transmission power. The key technologies have been Relatively mature and widely used in power transmission systems. [0003] The LCC converter station consumes a large amount of reactive power, which is critical to maintaining the AC bus voltage and maintaining the stable operation of the system. Therefore, it is necessary to configure a reactive power compensation device with corresponding capacity. The conventional r...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the situation that when the new energy power generation is sent through the LCC, the switching times of the AC filter increase due to the fluctuation of the new energy output, which affects the stability of the system operation, and the stepped switching method of the AC filter, the adjustment of the reactive power Continuity has limited problems; the present invention proposes a power coordination control method suitable for LCC DC transmission systems, which provides new ideas and new directions for the development of new energy DC grid-connected technologies, and solves the problem of renewable energy power generation The defect that the power fluctuation cannot cooperate with the LCC type DC transmission system improves the frequent action of the conventional reactive power compensation device during system operation, realizes fast reactive power control, and keeps the voltage and power stable and balanced, thereby ensuring system operation and power transmission stability

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