Experimental investigation of existing methodologies for the Responsibilities Assignment Problem (original) (raw)

Discussion on existing methodologies for the Responsibilities Assignment Problem

2008 International School on Nonsinusoidal Currents and Compensation, 2008

This paper introduces the Responsibilities Assignment Problem (RA P) and discusses existing methodologies by theory and examples. The RA P can be understood as the evaluation and determination of the power quality disturbances and of the power quality conditions detriment concerning source and amount. Selected details of this problem are presented in this paper, in order to provide a conceptual background to understand the problem itself and to interprete the characteristics of the currently available assessment methodologies. The existing methodologies are summarized, their principles, characteristics, and application are illustrated by means of an example. From the application results, a comparison of the mentioned methodologies is shown to point out advantages and differences. In the framework of the conference this paper could start and support a discussion about the assigment of responsibilities related to power quality disturbances propagation and improvements of the existing methodologies.

Method of Disturbances Interaction: Novel approach to assess responsibilities for steady state power quality disturbances among customers

Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010, 2010

A new method to decompose currents in electrical circuits in order to analyze stationary power quality disturbances is presented in this paper. A set of reference conditions allows the definition of the desirable load behavior regarding power quality. The decomposition permits to analyze separately three stationary phenomena, waveform distortion, asymmetry and phase displacement. A discussion about the problem is responsibilities is presented as well.

Study of Power Quality Disturbance for Restructuring of Power Systems

In recent years, the traditional power systems’ structures have been changed, and the concern over power quality has increased due to the new generation of load equipments. This equipments has been fully automated electronically, so it can be highly sensitive to any power quality disturbances. Indeed, power quality disturbances may cause malfunctions in the equipment, which leads to higher production costs due to decreased production efficiency. Moreover, the electronic converters in these loads produce harmonic currents that increase current distortion. Eventually, the impact of electronic converters on power quality will be increased proportional to the converters lifetime; therefore, maintaining power quality levels above specific baselines will be an essential requirement in future decades.

DETAILED CLASSIFICATION OF VARIOUS CATEGORIES OF POWER QUALITY PROBLEMS

In the recent years, power quality has been a research area of exponential increasing interest due to the wide utilization of power electronic devices. A high level of power quality is required to ensure the proper and continuous operation of the sensitive equipments such as power electronic drives, computers and microprocessor-based controllers. This necessitates the detection and monitoring of power quality problems. This paper presents a simple algorithm to detect and classify various categories of nonstationary power quality problems. The algorithm takes the sampled 3-phase instantaneous voltages which are measured at the point of common coupling and computes RMS and DC values. Based on the calculated values and number of samples, the power quality problem is classified. This algorithm is implemented using MATLAB programming and is tested for various categories of power quality problems such as sag, swell, interruption; under voltage, over voltage, unbalance and DC offset.

Development of Power Quality Control Procedures and Standards To Control the Connection of Non-linear Loads in Electric Power Systems

22nd International Conference and Exhibition on Electricity Distribution (CIRED 2013), 2013

The rise of new electric customers with type of load of iron smelting electric furnace has made PLN prompted to prepare adequate power supply, improved reliability of electricity supply and fix the rules of on standards and control procedures of electric power quality on customer's side. Load type iron electric furnace or iron smelters, has been known to cause power quality problems, especially harmonics, which may cause disturbance to other consumers or to electrical power system. Therefore, procedures to supervise and to control customer's electrical load which causing power quality problems need to be developed and implemented to maintain the power system from voltage and current harmonic distortion problem and the influence of other power quality problems. Also, power quality standard as the major rules regarding the limitation of power quality distortions has to be established and consistenly implemented including on the letter of power purchase agreement between utility and electricity customer. This paper shows the efforts of PLN to develop supervision and control procedures and power quality standards for limiting the distortion power quality and also the preparatory steps for applying the rule on each electric power customer's. Implementation strategies for applying the power quality limitation rule to both news customers and existing customers are described in detail.

Measuring electric power quality: Problems and perspectives

Measurement, 2008

The proliferation of non-linear and time-variant loads is causing a number of disturbances on the electric network, from a more and more significant distortion of both currents and voltages, to transient disturbances on the supply voltage. In this respect the electric network behaves as an ''healthy carrier'' of disturbances, so that a disturbance generated by one customer can be distributed to other customers, causing possible damage to their equipment. The measurement of the quality of the electric power in a network section is therefore becoming an impelling need, especially in a deregulated electricity market, where each actor can be responsible for the injection of disturbances. However, there are still some respects of power-quality measurement, from both the methodological and instrumental point of views, that are still unsolved and require to be carefully analyzed. The paper gives a survey of these problems and some indications about the present trends of the research work in this field.

A new unified approach to power quality management

IEEE Transactions on Power Electronics, 1996

A new control algorithm for a converter-based device that is capable of alleviating the problems of harmonic interference and voltage regulation on radial distribution lines is introduced. It comprises a relocatable converter in series with a passive filter and is called the Power Quality Manager. Simulation results based on an existing 88-kV line are presented. Experimental results are presented, based on a three-phase 200-VA scaled model of the existing 88-kV system. It is a cost-effective and flexible solution to improving power quality. NOMENCLATURE Impedance of the passive filter. Line impedance. Line current. Load current. Passive filter current. Supply voltage. Terminal voltage. Converter output voltage. DC bus voltage of converter. Reactive load power. Total reactive power through line. Total compensator reactive power. Converter reactive power. Active impedance. Control parameter representing fraction of line voltage injected. Load apparent power. (Subscript) harmonic. (Subscript) fundamental. I. INTRODUCTION N A POWER GRID where the generation centers are I concentrated in one area and power has to be delivered to areas far from the generation zone, many of the distribution lines are necessarily of a radial nature. Voltage regulation on these lines is often insufficient due to the long distance from the source, resulting in a large line impedance. Industries with Manuscript

-Power Quality (PQ) Survey Reporting Discrete Disturbance Limits

Discrete or event type power quality (PQ) disturbances mainly include voltage sags, swells, and the transients. An extensive literature survey suggests that there is no generally accepted method for characterization of these disturbances and suitable limits are not yet found in any international standard. One of the reasons for the lack of characterization methods is the difficulty of defining suitable site indices for each discrete disturbance type. In this paper existing characterization methods are reviewed and discussed. A new generalized approach is then given to show a better way of characterizing voltage sags, swells and transients. This is followed by a proposed new method of defining MV/LV distribution discrete disturbance limits for general utility networks and their suitability is shown by an examination of some Australian sites.