Power system harmonics research: a survey

Abstract

SUMMARYThe increased use of power electronic controlled equipment, such as variable speed drives, automated production lines, personal computers and non-linear electronic devices in power systems has given rise to a type of voltage and current waveform distortion called as 'harmonics'. Harmonic can be defined as the undesirable components of a distorted periodic waveform whose frequencies are the integer multiples (non-integer multiples in case of inter-harmonics, and the frequency less than fundamental frequency in case of sub-harmonics) of the fundamental frequency. Presence of these harmonics results in increased losses, equipment heating and loss-of-life, and interference with protection, control and communication circuits as well as customer loads. The research has been underway since very beginning for control of power system harmonics and to supply consumers with reliable and 'clean' fundamental-frequency sinusoidal electric power that does not represent a damaging threat to their equipment. This paper, therefore, reviews the progress made in power system harmonics research and development since its inception. Attempts are also made to highlight the current and future issues involved in the development of quality and reliable electric power technology for future applications. A list of 145 research publications on the subject is also appended for a quick reference.

A Single-Point Method Based on Distortion Power for the Detection of Harmonic Sources in a Power System

“…Table 1 summarizes the state of the art of single-point methods that are used for harmonic source detecting or sharing harmonic responsibility between utility and consumer. One of the most common used single-point strategies from Table 1 (APD) is based on monitoring the sign of the harmonic active power P H [1,11,12]. According to this method a consumer represents a source of harmonic pollution just in case when P H < 0.…”

“…Otherwise, the utility-side pollutes the power grid. This identification of the nonlinear consumer is widespread and has been used in the industry for many years [1,12]. Many manufactures present this possibility as a key feature of their equipment despite the proofs that it is not 100% accurate [12].…”

“…Therefore, AC to DC converters have become the most numerous loads in a power grid. Unfortunately their nonlinear nature generates harmonics in the power network causing numerous unwanted problems [1,2,3]. The permanent growth of the number and types of nonlinear loads aggravates the problems caused by harmonics.…”

“…That enforced almost every country to introduce its own standard that restricts the allowed amount of each harmonic. Two widely known standards in this area are the IEEE 519-1992 and IEC 61000 series [1], [3]. The standard IEC/EN61000-3-2 entered into force in the European Union.…”

Harmonic assessment‐based adjusted current total harmonic distortion

“…Nowadays, the structure of the power system networks continues its complication because of the growth of the distributed generationbased renewable energy technologies, and the advance in the use of non-linear loads. Thus, much attention should be paid to power system harmonic distortion to meet the present and future requirements of quality of electric power systems [1][2][3][4][5].…”