Analysis of the influence of environmental conditions on the emission of partial discharges in electrical machines

The article presents the results of research which include an assessment of influence of selected microclimate parameters on the issue of partial discharges in high power drives in the energy sector. The author presented the results of their own research, which was made in industrial conditions in a long period of time. The study included measurement of environmental parameters such as the air temperature, radiant temperature, air flow velocity, humidity and the relative moisture of air. It also measured the parameters of partial discharges like: partial discharge intensity (PDI), the amplitude of discharges (Qmax) and the partial dis charge pulses per second (PPS). In summary, the author presents the recommended parameters of the environment, which are beneficial to long-term operation of electrical machines

Multiparameter evaluation of thermal comfort conditions

W artykule przedstawiono główne zagadnienia związane z badaniem komfortu cieplnego w ogrzewanych pomieszczeniach metodą pomiarową oraz z wykorzystaniem symulacji komputerowych. Przedstawione przykłady badań wskazują na potrzebę uwzględnienia w układzie automatycznej regulacji obiektywnej wielkości. Zdaniem autora parametrem takim może być wyznaczana temperatura odczuwalna.The paper describes influence of chosen quantities as well as construction and exploitation conditions of a heating system on heat-flow phenomena in a heated room. It is pointed out that the analysis of heat-flow phenomena can be a valuable source of information as regards methods for creating thermal comfort. The examples of investigations performed show the need of including an objective quantity in the automatic control system. The determined sensible temperature can be, according to the author, such a quantity. A mathematical model of the heat -flow phenomena in a heated room has been formulated taking into consideration complex heat exchange and air infiltration from the outdoors. Measurements of thermal comfort conditions have been taken and numerical simulations have been performed when taking into account the influence of variable external conditions, different heating techniques, ways of ventilation system arrangement on three-dimensional temperature profile, air motion velocity and radiation temperature. A test post has been designed and constructed, and a large number of experimental investigations have been conducted, including the one allowing verification of computation results

Analysis of the influence of microclimate on the emission of partial discharge in electrical machines

The paper present results of measurements of selected parameters of microclimate and their effects on the emission of partial discharge of electrical machines. The study was conducted in industrial conditions by measuring the air temperature, radiant temperature, air speed and relative humidity of air at the same time recording the condition of PD induction motor, an annular high-voltage high-power, which is one of the drives critical cement. Based on the survey findings will be formulated which will define the relationship between changing climate and emission magnitudes of partial discharges

An analysis of the influence of microclimate on partial discharge activity in emissions of electric machines in the conditions of industrial operation – own research

The article presents the results of diagnostic measurements of partial discharge signal propagation from the winding insulation in electrical machinery, which were performed using an on-line method. This paper describes the results of experiments and the acquired experience in the monitoring of winding insulation in high power and high voltage electrical machines which are important in industrial production processes. The authors show the measurement techniques employed in their research. Representative measurement results are presented along with their analysis. The authors use an SKF monitoring systems to measure: vibrations, temperature, and humidity, as major factors affecting partial discharge activity in the from winding insulation of electrical machines

An analysis of the influence of microclimate on partial discharge activity in emissions of electric machines in the conditions of industrial operation – own research

The article presents the results of diagnostic measurements of partial discharge signal propagation from the winding insulation in electrical machinery, which were performed using an on-line method. This paper describes the results of experiments and the acquired experience in the monitoring of winding insulation in high power and high voltage electrical machines which are important in industrial production processes. The authors show the measurement techniques employed in their research. Representative measurement results are presented along with their analysis. The authors use an SKF monitoring systems to measure: vibrations, temperature, and humidity, as major factors affecting partial discharge activity in the from winding insulation of electrical machines

The electric machines working in different microclimatic conditions

The article presents the results of research which include an assessment of influence of selected microclimate parameters on the issue of partial discharges in high power drives in the energy sector. The authors presented the results of their own research, which was made in industrial conditions in a long period of time. The study included measurement of environmental parameters such as the air temperature, radiant temperature, air flow velocity, humidity and the relative moisture of air. It also measured the parameters of partial discharges like: partial discharge intensity (PDI), the amplitude of discharges (Qm) and the partial discharge pulses per second (PPS). The article also provides the model assumptions which describe the heat flow phenomena in industrial hall room with working electrical drives. The results of the simulations have been verified by obtaining satisfactory qualitative and quantitative convergence between the experimentation and simulation. In summary, the author presents the recommended parameters of the environment, which are beneficial to long-term operation of electrical machines

The Thermal Comfort of Hv Electrical Machines

This article describes a definition of thermal comfort and how to determine the conditions of thermal comfort for high voltage electrical machines using at work. The basis for determining the conditions of comfort is to measure the PD and microclimate measured on-line methods in industrial use. The proposal involves the determination of the temperature and moisture and relative humidity at which the PD activity is at a very low level. Presented in this paper results of the study show the existence of such microclimatic conditions in which the level of PD activity can be reduced to a minimum. Note, however, that designated this way microclimatic conditions do not adversely impact other operating parameters of electrical machines.W artykule przedstawiono definicję pojęcia i sposób wyznaczania warunków komfortu cieplnego maszyn elektrycznych wysokiego napięcia na podstawie pomiaru aktywności wyładowań niezupełnych (wnz) oraz parametrów mikroklimatu mierzonych metodami on-line w warunkach przemysłowej eksploatacji. Propozycja polega na wyznaczeniu takiej temperatury i wilgotności powietrza, przy których aktywność wnz jest na bardzo niskim poziomie. Przedstawione w artykule wyniki badań własnych dowodzą istnienia takich warunków mikroklimatycznych, w których poziom aktywności wnz może zostać zredukowany do minimum. Należy jednak pamiętać, aby wyznaczone tym sposobem warunki mikroklimatyczne nie wpływały negatywnie na pozostałe parametry eksploatacyjne maszyn elektrycznych

Determining the Electrical Machines Thermal Comfort by Measurement of Pd Activity

This article describes how to determine the conditions of thermal comfort for high voltage electric al machines using at work. The basis for determining the conditions of comfort is to measure the PD and microclimate measured on-line methods in industrial use. The proposal involves the determination of the temperature and moisture and relative humidity at which the PD activity is at a very low level. Presented in this paper results of the study show the existence of such microclimatic conditions in which the level of PD activity can be reduced to a minimum. Note, however, that designated this way microclimatic conditions do not adversely mpact other operating parameters of electrical machines.W artykule przedstawiono sposób wyznaczania warunków komfortu cieplnego maszyn elektrycznych wysokiego napięcia na podstawie pomiaru aktywności wyładowań niezupełnych (wnz) oraz parametrów mikroklimatu mierzonych metodami on-line w warunkach przemysłowej eksploatacji. Propozycja polega na wyznaczeniu takiej temperatury i wilgotności powietrza, przy których aktywność wnz jest na bardzo niskim poziomie. Przedstawione w artykule wyniki badań własnych dowodzą istnienia takich warunków mikroklimatycznych, w których poziom aktywności wnz może zostać zredukowany do minimum. Należy jednak pamiętać, aby wyznaczone tym sposobem warunki mikroklimatyczne nie wpływały negatywnie na pozostałe parametry eksploatacyjne maszyn elektrycznych

Brown coal low-temperature drying for power plants. Own research

Autorzy przeprowadzili serię eksperymentów używając innowacyjny system suszenia węgla brunatnego metodą fluidalną w niskich temperaturach czynnika suszącego (powietrza): 25-70°C. Badania prowadzono na węglu brunatnym ze złoża w Bełchatowie i Turoszowie, zakres badań dotyczył wielkości ziaren: 0-0,4; 0,4-2; 2 -4; 4-6,3 i ponad 6,3 mm. W artykule przedstawiono termo-kinetyczne właściwości badanych węgli, między innymi określono wpływ wielkości ziarna i struktury węgla oraz stopień wilgoci na intensywność procesu suszenia w funkcji temperatury czynnika grzewczego i czas trwania procesu. Ponadto, poprzez monitorowanie parametrów suszenia wyznaczono krzywe poboru energii do odparowania jednego kilograma wody z mokrego węgla brunatnego w ustalonych warunkach, a tym samym ustawiając optymalny obszar dla parametrów procesu suszenia ze względu na kinetykę procesu jak i nakład energetyczny.The authors conducted series of experiments using an experimental brown coal drying system with fluid bed method in the low medium (air) temperature: 25-70°C. The study was conducted on brown coal from a deposit of Bełchatów and Turoszów, range of tests concerned the grain size: 0-0,4; 0,4-2; 2 -4; 4-6,3 and more than 6.3 mm. In the paper are presented the thermo - kinetic properties of studied coals, inter alia: is determined the effect of grain size and structure of coal and its degree of moisture on the intensity of the drying process as a function of changing temperature of the heating medium and the duration of the process. In addition by monitoring the drying process parameters, curves of the energy input for evaporation of 1 kg water from wet brown coal were determined, thus setting the optimum area for the parameters of the drying process (due to kinetics of the process and energy consume)

The analysis of the influence of environmental conditions on the emission of partial discharges in electrical machines

The article presents the results of research which include an assessment of influence of selected microclimate parameters on the issue of partial discharges in high power drives in the energy sector. The author presented the results of their own research, which was made in industrial conditions in a long period of time. The study included measurement of environmental parameters such as the air temperature, radiant temperature, air flow velocity, humidity and the relative moisture of air. It also measured the parameters of partial discharges like: partial discharge intensity (PDI), the amplitude of discharges (Qmax) and the partial discharge pulses per second (PPS). In summary, the author presents the recommended parameters of the environment, which are beneficial to long-term operation of electrical machines