直流输电换流站无功功率控制功能设计

直流输电系统无功功率控制的目的是保证交直流系统的无功交换满足系统要求,同时减轻换流站谐波对交直流系统及主设备的危害.实际工程中无功控制主要通过对交流滤波器组等无功单元的投切实现.需要考虑的因素有,交直流系统无功交换的平衡、交流系统稳态电压的限制、基本滤波条件的保证和滤波性能的优化、无功单元投切的均衡性、投切过程对系统的扰动等.直流输电系统的无功控制是一种多目标、多边界条件的复杂控制功能.按照实际工程的要求,对直流输电无功控制功能和策略的设计进行了全面的分析和介绍.

Design of reactive power control for HVDC converter station

The purpose of the reactive power control of HVDC system is to balance the reactive power exchanged between the AC and DC systems, and also to mitigate the harms of the harmonics produced by the converters to the system and the primary equipments. The reactive power control is realized mainly by switching of AC filter sub-banks on and off in stepped manner. Different aspects have to be considered for the reactive power control including the quantity of the reactive power being exchanged, limitation of steady state AC voltage, demands and optimizing of harmonic filtering, switching equalization of the sub-banks, elimination of disturbance caused by the sub-bank switching etc. The HVDC reactive power control is of complicated multi-target and multi-boundary control function. Based on the requirement in real HVDC project, the design principle for detailed functions and strategies of reactive power control are analyzed and introduced in this paper.