Power quality indices and objectives. Ongoing activities in CIGRE WG 36-07

Abstract

This paper gives an overview of the ongoing activities in CIGRE WG36-07: "Power quality indices and objectives". It introduces the considerations supporting the need for power quality indices and objectives in the present context of deregulation of the electricity industry. Experts generally agree on the need for standardized quality indices allowing to monitor and to report power quality in a common format. However, concerning quality objectives the need is more likely for different levels of quality that can match customers expectations and the price they are willing to pay for electricity. Some practical limitations to voltage quality monitoring are also discussed. The status of the work within the working group is described for harmonics, flicker, unbalance and voltage dips.

Energy Storage Characteristic Analysis of Voltage Sags Compensation for UPQC Based on MMC for Medium Voltage Distribution System

“…In many power quality problems, the reliability of a power supply system for voltage sag has been an important issue [24]. With the development of microelectronics, computers, power electronics technologies, renewable energy power generation systems, user equipment, and access systems that are able to process more information, the equipment used to detect voltage sag is very sensitive, causing many troubles and huge losses for stakeholders.…”

Stability Enhancement in Nine Bus System with STATCOM

“…Static synchronous compensator (STATCOM) is a custom power device which is based on a voltage source converter (VSC) shunt connected to the network [1]. By injecting a controllable current, a STATCOM can mitigate voltage dip at the point of connected with the network and enhance system stability.…”

“…As a consequence, attempts at power flow solutions near the critical point are prone to divergence and error. For this reason, double precision computation and anti divergence algorithms have been used in attempts to overcome the numerical instability [1][2]. The interest in system stability is due to the problems they cause on several effect on system.…”

S-Transform Based Novel Indices for Power Quality Disturbances

“…The opening of power markets, and the deregulation and restructuring throughout the world are further changing the framework in which power quality is addressed (Beaulieu et al, 2002). Therefore, the techniques for power quality study and power disturbance mitigation are capturing increasing attention, and consequently, manufacturers are integrating power quality monitoring functions in their products such as power meters, digital relays and event recorders (Ward, 2001).…”