1. New Metric Recommended for IEEE Standard 1547 to Limit Harmonics Injected Into Distorted Grids.
- Author
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Zong, X., Gray, P. A., and Lehn, P. W.
- Subjects
ELECTRIC power distribution grids ,ELECTRIC standards ,CONVERTERS (Electronics) ,ELECTRIC potential ,HARMONIC distortion (Physics) - Abstract
IEEE Standard 1547 defines grid connection standards for distributed resources (DRs). This standard sets requirements for harmonic performance, which are particularly relevant when converter-interfaced DRs are considered. Specifically, the standard limits the allowable harmonic current injected by a DR, assuming grid voltage at the point of common coupling (PCC) is harmonic free. In this paper, it is demonstrated, both mathematically and experimentally, that the harmonic current injection of a converter-interfaced DR depends highly on the level of PCC background voltage. This paper presents a mathematical formulation that enables the impact of PCC voltage harmonics on the harmonic current injection of a converter-interfaced DR to be determined via experimental identification of the converters frequency coupling matrix. Experimental tests show that an IEEE 1547-compliant solar inverter with measured total demand distortion (TDD) of 0.66% for an undistorted PCC can produce TDD levels in excess of 20% in the presence of 3% voltage distortion. It is concluded that TDD metrics, as employed in IEEE Standard 1547, provide little insight into the field performance of converter-interfaced DRs when background voltage harmonics are present. Improved FCM-based metrics for assessing the harmonic performance of converter-interfaced DRs in the presence of voltage harmonics are provided. [ABSTRACT FROM PUBLISHER]
- Published
- 2016
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