Global assessment of power quality performance of networks using the analytic hierarchy process model

Abstract

Abstract-Power Quality is one of the critical issues when operating contemporary distribution networks. The increased interest in PQ is due to the increased employment of sensitive equipment loads and renewable generation technologies. Currently, the evaluation of PQ network performance is based on evaluating different phenomena separately, and a standardised way to evaluate the PQ as a whole for a bus or a network is yet to be applied or widely accepted. The paper presents a methodology for combining the performances of different PQ phenomena and expressing the PQ performance of a bus using a single index. The proposed methodology adopts an Analytic Hierarchy Process (AHP) model to combine the harmonics, unbalance and voltage sag performances in one proposed index; i.e. Compound Bus PQ Index (CBPQI). The separate and cumulative PQ performances of a 295-bus generic distribution network were evaluated, compared and demonstrated using heat maps.

Zonal Mitigation of Power Quality Using FACTS Devices for Provision of Differentiated Quality of Electricity Supply in Networks With Renewable Generation

“…Various approaches have been proposed in the past to represent the aggregate PQ performance at the bus, including artificial neural network, fuzzy logic, weighting functions and analytic hierarchy process (AHP) method [17][18][19]. In this paper, PQ performance is aggregated using a revised AHP [20], which consists of four steps: 1) Assess performance index of each PQ phenomenon denoted as I k ; identify the performance of its critical state denoted as IC k . The critical state, threshold, can be set based on standards or experts opinion in which case it can vary from bus to bus depending on expert's perception of importance of particular phenomenon for customers connected at given bus.…”

“…Various approaches have been proposed in the past to represent the aggregate PQ performance at the bus, including artificial neural network, fuzzy logic, weighting functions and analytic hierarchy process (AHP) method [17][18][19]. In this paper, PQ performance is aggregated using a revised AHP [20], which consists of four steps:…”

“…Further details can be found in [20]. Different from other aggregated indices, standard specified critical PQ performance state is integrated in the aggregation procedure by (4), as it is believed that the inclusion of standard specified thresholds is essential to keep the methodology as relevant to industrial practice as possible.…”

“…The principle eigenvectors of the pair-wise comparison are taken as the priority for each phenomenon (p k ). 4) Aggregate PQ performance based on:where K=3, the total number of considered PQ phenomena, For convenience, the aforementioned procedure of deriving the aggregated PQ performance is denoted as AHP, and the Unified Bus Performance Index (UBPI) can be obtained byFurther details can be found in [20]. Different from other aggregated indices, standard specified critical PQ performance state is integrated in the aggregation procedure by (4), as it is believed that the inclusion of standard specified thresholds is essential to keep the methodology as relevant to industrial practice as possible.…”

Assessment of Power Quality performance in distribution networks part II - Performance Indices and ranking of network buses

“…This paper presents and compares two global PQ indices based on monitoring data from a long term PQ measurement campaign presented in Part I of the paper. The application of the Compound Bus PQ Index (CBPQI) [18] and the Aggregated PQ Index (APQI), which is based on [19], for overall PQ performance ranking of network buses is illustrated and discussed. The indices limitations and strengths are highlighted.…”