谐波环境下配电线路损耗的计算方法与实验研究

Calculation Method and Experimental Study of Distribution Line Loss in Harmonic Environment

谐波流过配电线路会产生额外的谐波损耗,引起电能损失等经济性问题。为了准确计算线路的谐波损耗,需要明确线路谐波电阻的计算方法。首先总结了线路谐波电阻的理论计算方法,基于此对谐波作用下导体内的电流密度分布函数进行分析,推导出导体表面谐波电阻的计算公式。然后基于导体内谐波电流密度分布情况提出了加入修正系数计算多芯绞线谐波电阻的方法,仿真验证了贝塞尔函数计算导体表面谐波电阻的正确性,明确了经验公式的适用范围,并确定了计算铝绞线谐波电阻的修正系数。最后通过实验测量验证了修正系数法计算多芯绞线谐波电阻的可行性。该方法所需参数少,计算简单,适用于工程上快速计算线路的谐波损耗,对配电网节能降损具有重要意义。

When the harmonic current flows through distribution lines,it will generate additional harmonic loss and cause economic problems such as power loss.In order to calculate the harmonic loss of the line accurately,it is necessary to clarify the calculation method of the line harmonic resistance.First,the theoretical calculation method of line harmonic resistance was summarized.Based on this,the harmonic current density function in the conductor was analyzed,and the formula of harmonic resistance in the conductor surface was deduced.Then,according to the distribution of the harmonic current density in the conductor,a method of adding a correction coefficient to calculate the harmonic resistance of the multi-core stranded wire was proposed.Through simulation experiments,the validation of calculating the harmonic resistance of the conductor’s surface by the Bessel function was verified,and the applicable range of empirical formula was clarified,and correction factor for harmonic resistance of aluminum stranded wire was determined.Finally,the feasibility of Correction Coefficient Method to Calculate Harmonic Resistance of Multi-core Stranded Wire was verified.The method proposed in this paper requires fewer parameters and the calculation is simple.It’s suitable for calculating the harmonic loss of the line rapidly on engineering,which is of great significance to the energy saving and loss reduction of the distribution grid.