ABSTRACT The IEEE Std 519–2022 IEEE Standard for harmonic control in electric power systems is widely used for controlling the harmonics in the electric power system. It uses the total demand distortion (TDD) for current harmonic evaluation at the point of common coupling (PCC). According to IEEE 519–2022, current harmonic assessment for site installations with inverter‐based resources (IBRs) or distributed energy resources (DERs) is based on a decision tree. As per the decision tree, any site installation with a combined rated site generation exceeding 10% of the annual average load demand shall utilize the total rated current distortion (TRD) method, as specified in IEEE Std 1547, for evaluating current harmonics. For a combined DER rating from 10% to 90% of annual average load demand, TRD evaluates the higher current harmonic distortion, leading to an additional/higher rating of harmonic mitigation devices (i.e., harmonic filters) to comply with the current harmonic limits. The authors of this paper propose a new index, called ‘total distortion (TD)’, to evaluate current harmonic distortion and overcome the shortcomings mentioned above. Modeling and harmonic analysis are performed in DigSILENT PowerFactory software to calculate harmonic distortions. The effectiveness of the TD over the TDD and TRD index is analysed for an example of an e‐Bus charging station with a combined rated generation (i.e., DERs) of different sizes. Using the TD method for current harmonic evaluation minimizes the additional harmonic filter requirements (1 × 195 kVAr tuned for a 245 Hz maximum value) to comply with the IEEE Std 1547 limits, as compared to the TRD method. The authors propose a new decision tree for evaluating current harmonics at the site installation, considering both internal loads and DERs/IBRs, and recommend it to IEEE Std 519, IEEE Std 1547, and IEEE Std 2800.
P et al. (Thu,) studied this question.