基于无功功率方向法的主谐波电流来源判别

针对目前谐波电流造成特定线路各元件损耗难以明确其来源的问题，提出一种基于无功功率方向法来判别引起公共连接点（point of common coupling，PCC）处的主谐波电流来源方法。通常情况下，系统侧和用户侧谐波源流过特定线路各元件造成的损耗大小，可由两侧各自贡献的谐波电流大小区分，故以谐波电流指标为判别依据。以电网中谐波阻抗基本性质为基础，结合PCC处谐波电压和电流实测信息，利用基本电路原理和不等式约束条件，在谐波无功功率方向法的思路与判别条件下，推导得出了仅根据谐波电压和电流的相角差，就可直接判别主谐波电流来源的方法。最后，通过多种实际工程场景的实测数据，验证了该方法的有效性，使用中的便捷性反映了该方法在工程实用中的价值。

Identification of Main Harmonic Current Sources Based on the directions of Reactive Power

Currently it is difficult to pinpoint the origin of power loss in power system components as caused by harmonic current. To solve this problem, the paper proposes a method to locate harmonic current sources at the Point of Common Coupling (PCC) based on the directions of reactive power. Normally the power loss caused by harmonic current flowing through power system components can be attributed to be from either power system side or user side. The attribution is indicated by harmonic current index. The paper proposes a method to identify harmonic current sources (either power system side or user side) based on the phase difference between harmonic voltage and current. The proposed method is based on the harmonic impedance characteristics of the power system, measured harmonic voltage and current at PCC, circuit theory and inequality constraint. Finally, the approach is demonstrated and validated by the real data obtained in field tests. Experimental results suggest that the proposed approach is not only convenient to use but also has great engineering value.