浮式电站黑启动方式下谐波影响因素及其表征

Harmonic Influencing Factors and Their Characterization Under Black Start Mode of Floating Power Station

浮式电站使用静止变频器对浮式电站机组进行黑启动时,由于运行于孤网系统且电气结构受限,产生的谐波影响相比于陆上电站更加严重。对于浮式电站黑启动过程中产生的谐波与其影响因素之间的关系,目前还缺少理论研究。为此,对浮式电站黑启动过程谐波影响因素及其表征进行研究。首先,建立了浮式电站黑启动过程的等值电路;其次,基于等值电路对谐波表达式进行推导分析,得到谐波畸变率关于其影响因素的表达式,进而提出一种谐波影响因素的表征参数——谐波作用系数,并探讨了谐波作用系数的物理意义及应用;最后,通过仿真算例验证分析谐波畸变率和谐波作用系数的关系,得到二者正相关的结论,表明了谐波作用系数的合理性和有效性。

When floating power stations use static frequency converters to black-start floating power station units,the harmonic effects are more serious than onshore power stations due to the isolated grid system and the limited electrical structure.There is still a lack of theoretical research on the relationship between the harmonics generated during the black start process of floating power stations and their influencing factors.Firstly,the equivalence circuits on the black-start process of floating power stations were presented.Then,the mathematically analysis of harmonics was carried out on the basis of equivalence circuits,and the expression of the total harmonic distortion on its influencing factors was obtained.Furthermore,a characterization parameter of harmonic influencing factors,namely harmonic interfere coefficient,was proposed,and the physical meaning and application method of harmonic interfere coefficient were discussed.Finally,a simulation example was used to analyze the relationship between the total harmonic distortion and harmonic interfere coefficient.It is concluded that the harmonic interfere coefficient is positively correlated with the total harmonic distortion,which shows the rationality and effectiveness of the harmonic interfere coefficient.