中文摘要：

为直流融冰技术在电网中的应用提出了一种新型柔性直流融冰技术。通过分析输电线路结冰情况的等效模型并研究融冰时的热交换过程,针对220kV输电线路计算出了线路融冰所需的保线电流和最大电流值。按计算结果的需求设计了基于可关断器件的新型柔性直流融冰电源。论述了该电源的主电路拓扑及其功率单元的等效电路,并对其相关的融冰控制策略进行了分析和研究。最后研制出一台全控直流融冰装置样机,并进行了现场试验。试验结果表明,该融冰装置可对直流输出电压进行柔性调节,融冰时的网侧谐波含量较低,在试验中仅3.16%。

英文摘要：

To improve the application of DC ice-melting technology in power grids,a new type of flexible DC icemelting technology was proposed.Based on analysis on the equivalent model of frozen transmission lines and the heat exchange during ice-melting,the necessary anti-icing current and maximum current were calculated for a 220 kV power line.A novel flexible DC ice-melting power based on self-commutated semiconductors was designed according to the calculation results.The main circuit topology,mathematical model and control strategy of the power unit module were introduced and discussed.Finally,a full-controlled DC ice-melting device prototype was developed,of which the test has been carried out too.Test results show that the ice-melting device can regulate DC output flexibly,while the harmonic contents on line side,which is only 3.16%in the test,also meet requirements.