Voltage value influence estimation on the measurement results for the optical radiation generated by surface partial discharges in stand-off isolator

Tematyka artykułu dotyczy określenia możliwości i wskazania zakresu zastosowania metody spektrofotometrii optycznej w diagnostyce izolatorów liniowych i stacyjnych. W artykule przedstawiono wyniki pomiarów promieniowania optycznego emitowanego przez wyładowania niezupełne generowane na modelu izolatora wsporczego. Podstawowym celem przeprowadzonych badań była ocena wpływu zmian wartości napięcia zasilającego na intensywność i charakter zarejestrowanych widm promieniowania optycznego.The subject area of the paper concerns the determination of possibility and application scope suggestion for the optical spectrophotometry method in the linear isolators' diagnosis. Measurement results of the optical radiation emitted by surface partial discharges generated in a model of the stand-off isolator, which was placed in the air, are presented in the paper. Recording was done by use of a spectrophotometer that enabled for measurement of optical radiation in the range of 270 to 1600 nm. The main aim of laboratory research works performed was to estimate the influence of the supply voltage value changes in range of 0 to 0,98 Ub (breakdown voltage) on the intensity and character of the optical radiation spectrum emitted by surface partial discharges occurring in the ceramic insulating surface of the stand-off isolator. In the scope of research works the analysis of voltage value change influence on the gathered spectra was performed while its accretion and decrease was investigated. Furthermore, the measurements and analysis performed enclose the influence estimation of the time, when the voltage was attached to the high voltage electrode, on the proceeding of the optical phenomena connected with generation of surface partial discharges

Assumptions for the expert system of partial discharge measurements using the optical spectrophotometry method

Tematyka niniejszego artykułu dotyczy doskonalenia praktycznych zastosowań metody spektrofotometrii optycznej w diagnostyce wysokonapięciowych układów izolacyjnych urządzeń elektroenergetycznych, wykonywanej podczas ich normalnej pracy w warunkach przemysłowych. W artykule przedstawiono możliwości rozpoznawania podstawowych form wyładowań elektrycznych na podstawie wyników analizy widm optycznych emitowanego podczas ich występowania promieniowania elektromagnetycznego. W szczególności w celach porównawczych zestawiono wartości wybranych deskryptorów tj. wartości średniej (tabela 1) i maksymalnej (tabela 2) intensywności promieniowania optycznego emitowanego przez wybrane formy wyładowań elektrycznych zupełnych i niezupełnych, jakie mogą występować w powietrzu i oleju izolacyjnym. Wartości zostały wyznaczone dla trzech wybranych pasm długości fal promieniowania tj. UV (ultrafioletowego) / VIS (widzialnego) / NIR (bliskiej podczerwieni). Ponadto w artykule scharakteryzowano koncepcję systemu diagnostycznego oceny wyładowań niezupełnych opartego na wynikach uzyskiwanych przy zastosowaniu metody spektrofotometrii optycznej. Zaproponowany system oparty jest na zastąpieniu spektrofotometru czujnikiem składającym się z trzech detektorów promieniowania optycznego, czułych na fale w zakresach UV, VIS i NIR. Schemat blokowy systemu przedstawiono na rys. 1. W podsumowaniu scharakteryzowano zakres realizowanych obecnie prac naukowo-badawczych w Instytucie Elektroenergetyki związanych z praktyczną implementacją zaproponowanego systemu.This paper deals with the development of practical applications of the optical spectrophotometry method to diagnostics of high-voltage insulation systems of power appliances performed during their regular operation under industrial conditions. There are presented the possibilities for recognition of basic electrical discharge forms based on the analysis of optical spectra emitted during the appearance of electromagnetic radiation. For the purpose of comparison the values of selected descriptors are given. They are the mean values (Table 1) and the maximum (Table 2) optical radiation intensity emitted by selected forms of partial and disruptive electrical discharges which can occur in air and insulation oil. The values are determined for three selected bands of radiation wave lengths, i.e. UV (ultraviolet) / VIS (visible) / NIR (near infrared). Moreover, the concept of a diagnostic system for assessment of partial discharges based on the results obtained by using the optical spectrophotometry method is presented in this paper. The system proposed is based on replacement of a spectrometer with a sensor consisting of three optical radiation detectors, sensitive to waves in UV, VIS and NIR ranges. The block diagram of the system is shown in Fig. 1. In the concluding remarks there is characterized the research work conducted in the Institute of Power Engineering aimed at practical implementation of the system proposed

Analysis of camera application possibility for measurement of ultraviolet radiation emitted by partial discharges generated on a bushing isolator model

Tematyka artykułu dotyczy określenia możliwości i wskazania zakresu zastosowania w diagnostyce izolatorów liniowych i stacyjnych kamery rejestrującej promieniowanie ultrafioletowe. W artykule przedstawiono wyniki pomiarów promieniowania ultrafioletowego emitowanego przez wyładowania niezupełne powierzchniowe generowane na modelu izolatora przepustowego umieszczonego w powietrzu. W ramach przeprowadzonych badań dokonano analizy wpływu szeregu czynników metrologicznych na uzyskiwane wyniki.The scope of this paper considers possibility determination and application area indication of a camera for ultraviolet radiation recor-ding in diagnosis of linear isolators. Measurement results of ultraviolet radiation emitted by surface partial discharges (SPDs) generated on a bushing isolator mounted in the air are presented in the paper. Recording was performed by use a professional UVollé camera by the firm OFIL which enables for ultraviolet radiation measurement in the range of 50 nm to 280 nm. The main aim of works, performed under laboratory conditions, was to estimate the influence of supply voltage value changes in the range of 0 to 0.98 Up (breakdown voltage) on the counting quantity of partial discharges occurring on the surface of the ceramic bushing isolator. Moreover, the measurements and analyses performed, enclosed the influence estimation of the duration time of voltage applied to high tension electrodes, on the optical phenomena progress connected with SPDs generation. In the scope of works executed also the influence analyses of the distance between electrodes as well parameters of camera applied (sensitivity, amplification and size of the counting window) on the achieved results were investigated. Additionally, a comparative analysis of measurements results achieved for two diameters of the metal electrode (refill) for bushing isolator model was performed

Influence Estimation of the Voltage Value on the Measurement Results for the Optical Radiation Generated by Partial Discharges on Bushing Isolator

The subject area of the paper concerns determination of possibility and application scope suggestion for the optical spectrophotometry method in the linear isolators diagnosis. Measurements results of the optical radiation emitted by partial discharges generated on a model of bushing isolator, which was placed in the air, are presented in the paper. Recording was done by use of a spectrophotometer that enabled for measurement of optical radiation in the range from 250 to 1700 nm. The main aim of laboratory research works performed was to estimate the influence of the supply voltage value changes in range from 0 to 60 kV on the intensity and character of the optical radiation spectrum emitted by surface partial discharges occurring on the ceramic insulating surface of the bushing isolator. In the scope of research works, analysis of voltage value changes influence on the gathered spectra was performed while its accretion and decrease was investigated. Furthermore, the measurements and analysis performed enclose the influence estimation of the time, when the voltage was attached to the high voltage electrode, on the proceeding of the optical phenomena connected with generation of surface partial discharges. In addition a comparative analysis of measurements results gathered for two designed and implemented models of bushing insulators, which differ in geometric dimensions, was performed

Analysis of UV radiation generated by surface partial discharges

W artykule przedstawiono wyniki pomiarów intensywności względnej promieniowania ultrafioletowego (UV) zmierzone dla modelu izolatora szklanego umieszczonego w powietrzu. Promieniowanie generowane było przez wyładowania niezupełne. Badano wpływ wartości napięcia generacji wyładowań na intensywność emitowanego promieniowania optycznego. Ponadto analizowano wpływ odległości czujnika pomiarowego od elektrody, do której przyłożono wysokie napięcie.The article presents measurement results of ultraviolet relative radiation intensity measured for a model glass insulator placed in the air. The radiation was generated by partial discharges. The effect of voltage on intensity-discharge generation of optical radiation is emitted. Furthermore, the influence of the distance from the electrode sensor, to which high voltage was applied on the measurement results

Nonlinear modelling of Activated Sludge Process

A computer simulation model for the Activated Sludge Process (ASP) of a wastewater treatment plant (WWT) is presented in this paper. The model is based on non-linear equations, which depend on wastewater concentration and flow, which values vary with time. The proposed ASM1R3 model is a reduced version of the common ASM1 model due to the fact it involves only three state variables: Ss –the dissolved biodegradable organic substrate, SNO – the dissolved nitrate nitrogen and SNH – the dissolved ammonia nitrogen. In an experimental verification the model was considered as well fitted to empirical data. The proposed model is characterized by relatively low computational complexity and can be successfully applied as integral part of the overriding control systems of the WWT plant. As a result of conducted studies it was found that it is possible to apply the ASM1R3 model to optimize and improve the WWT process parameters of the regarded plant

Expert system for assessment of electric power transformer insulation systems using the acoustic emission method

Tematyka niniejszego artykułu dotyczy doskonalenia praktycznych zastosowań metody emisji akustycznej (EA) w diagnostyce wysokonapięciowych układów izolacyjnych urządzeń elektroenergetycznych. W szczególności przedstawiono podstawowe założenia oraz opisano poszczególne elementy eksperckiego systemu diagnostycznego wykorzystującego metodę akustyczną do oceny stanu mierzonej izolacji transformatorów energetycznych, wykonywanej podczas ich normalnej pracy w warunkach przemysłowych.The subject matter of this paper refers to the development of practical applications of the acoustic emission (EA) method to diagnostics of high-voltage insulation systems of power appliances, carried out during their regular operation in industrial conditions. First of all, basic assumptions are presented and the particular elements of the expert diagnostic system using AE method for the assessment of the condition of the electric power transformer insulation measured are described. Fig. 1 shows its block diagram in which the following modules can be distinguished: a measuring system (Figs. 2 and 3), a processing - analysing system, a knowledge base and a classifier. These modules are characterised successively in Section 2 of the paper. Special attention is given to the description of the group of multiparametric descriptors (Fig. 4) characterising the AE signals in the time, frequency and time-frequency domains, including descriptive statistics indexes and correlative parameters. Accordant descriptors make it possible, under strictly defined metrological conditions, to recognize basic partial discharge forms (PDs) that may occur in paper-oil insulation. In this way a catalogued knowledge base containing the so-called 'fingerprints' was created for basic types of high-voltage defects of insulation systems. The scope of the research work carried out in the Institute of Power Engineering, connected with a practical implementation of the system suggested, is characterised in the last section of the paper

Influence of a supply voltage value on the UV light generated by PD on HV cap insulators – a comparative analysis

The paper presents results of research works whose aim was to determine and indicate characteristics of optical signals emitted by corona discharges occurring in the vicinity of two types of high-voltage (HV) cap insulators. The experimental studies were performed under laboratory conditions using an ultraviolet (UV) camera. Two types of cap insulators were analyzed: one made of glass and the second one made of porcelain. For both considered insulating devices, the influence of supply voltage on the intensity of optical radiation was determined. The obtained results were analyzed and compared. Based on the results, it was stated that both cap insulators indicated similar characteristics but the most significant difference lied in the existence of the punch-through on the glass cap

The Application of the Correlative Analysis and the Regression Function for Determining Correlations οf the Measurement Results of Acoustic Emission Generated by Partial Discharges

The subject matter of this paper is connected with development of the assessment methods of results obtained at measurements of partial discharges occurring in insulation systems of power transformers using the acoustic emission method. The paper presents the results connected with determining correlation between partial discharge generation voltage and selected descriptors characterizing the emitted signals of acoustic emission in the frequency domain. Authors use the selected descriptors as comparative criteria for recognition of the basic partial discharge forms that may occur in paper-oil insulation of power transformers. The correlation coefficient and regression function were used to determine the correlation degree between the variables under study

Determination of hydrodynamic model based on tracer test performed in WWT plant in Kędzierzyn Koźle, Poland

Analysis results of lithium chloride concentrations, which were measured during tracer test performed in wastewater treatment (WWT) plant placed in Kędzierzyn–Koźle, Poland, are presented in the paper. The considered WWT plant operates with a five-stage Bardenpho system for organic content reduction within activated sludge process (ASP). One of the significant factors, which have an impact on the efficiency of the ASP in a biological reactor, is its hydraulic behavior. In this study theoretical and actual retention times were determined by using of mathematical modeling. Three single and multistream dispersion models were applied, i.e. Tanks-in-Series, Extended Tanks-in-Series and a model based on the MARTIN method. Using the last model it was possible to identify multiple wastewater flows in the reactors, which include: main flow and short circuiting flows. Furthermore, it was stated that the theoretical retention times differ from the actual values, obtained through mathematical modeling