Impulsstoiteseadmete põhjustatud häiringud madalpingevõrgus elektriliinsidele
Laen...
Kuupäev
2021
Kättesaadav alates
08.09.2021
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Lõputöös uuritakse impulsstoiteseadmete poolt põhjustatud kõrgesageduslikku müra madalpingevõrgus ja selle mõju PLC arvestite kauglugemisele. Üks rikkis toiteseade võib häirida kümnete arvestite kauglugemist ning nende seadmete leidmine ja asendamine on võrguettevõttele kulukas. Uuritavad toiteseadmed on müra põhjustajatena leitud ja eemaldatud Elektrilevi madalpingevõrgust Enefit Connecti töötajate poolt.
Lõputöö eesmärk on selgitada välja konkreetne põhjus, miks osad toiteseadmed hakkavad normaalsest märkimisväärselt kõrgemat võrgumüra tekitama. Lisaks püütakse välja selgitada, kui palju mõjutab rike toiteseadme väljundit. Uuritakse nelja erinevat impulsstoiteseadet. Uurimuse käigus tehakse mõõtmisi nii toiteseadme sisendi, kui ka väljundi poolel. Peale esialgseid mõõtmisi püütakse leida ja parandada toiteseadme rike, seejärel korratakse mõõtmisi samadel tingimustel ja võrreldakse saadud tulemusi.
Lõputöös uuritud toiteseadmetel õnnestus leida ja parandada võrgumüra põhjustav komponent. Kõikide uuritud toiteseadmete korral vähenes müra võrku genereerimine oluliselt peale silukondensaatori vahetust. Kolmel juhul neljal vähenes samal ajal oluliselt ka toiteseadme väljundpinge kõikumine. Teema on huvitav ka sellelt vaatenurgalt, et kelle kulul peaks võrgust eemaldama taolisi rikkes toiteseadmeid, mis üle lubatud normide võrgumüra põhjustavad. Seadmed võivad ohustada nii kliendi enda paigaldist, kui ka teisi lähedal olevaid kliendipaigaldisi. Hetkel on kõik seotud kulud jäänud võrguettevõtte kanda.
This thesis investigates the high-frequency noise caused by switched-mode power supplies in the low-voltage network and its effect on the remote reading of PLC meters. One faulty power supply can interfere with the remote reading of dozens of meters. Finding and replacing these devices is costly for the network company. The power supplies under investigation have been found to be causing noise and have been removed from Elektrilevi's low-voltage network by Enefit Connect employees. The aim of the thesis is to find out the specific reason why some power supplies start to generate significantly higher noise than normal. In addition, an attempt is made to determine how much the failure affects the output of the power supply. Four different power supplies are being studied. In the course of the study, measurements are made on both the input and output side of the power supply. After the initial measurements, an attempt shall be made to locate and rectify the failure of the power supply. Measurements shall be repeated under the same conditions and the results obtained compared. For all power supplies studied, the generation of noise in the network was significantly reduced after the replacement of the smoothing capacitor. In three cases out of four, the fluctuation of the output voltage of the power supply also decreased significantly. The topic is also interesting from the point of view of who should remove such faulty power supply devices from the network at their expense, which cause mains noise exceeding the permitted norms. The equipment may endanger the customer's own installation as well as other nearby customer installations. At the moment, all related costs are borne by the network operator.
This thesis investigates the high-frequency noise caused by switched-mode power supplies in the low-voltage network and its effect on the remote reading of PLC meters. One faulty power supply can interfere with the remote reading of dozens of meters. Finding and replacing these devices is costly for the network company. The power supplies under investigation have been found to be causing noise and have been removed from Elektrilevi's low-voltage network by Enefit Connect employees. The aim of the thesis is to find out the specific reason why some power supplies start to generate significantly higher noise than normal. In addition, an attempt is made to determine how much the failure affects the output of the power supply. Four different power supplies are being studied. In the course of the study, measurements are made on both the input and output side of the power supply. After the initial measurements, an attempt shall be made to locate and rectify the failure of the power supply. Measurements shall be repeated under the same conditions and the results obtained compared. For all power supplies studied, the generation of noise in the network was significantly reduced after the replacement of the smoothing capacitor. In three cases out of four, the fluctuation of the output voltage of the power supply also decreased significantly. The topic is also interesting from the point of view of who should remove such faulty power supply devices from the network at their expense, which cause mains noise exceeding the permitted norms. The equipment may endanger the customer's own installation as well as other nearby customer installations. At the moment, all related costs are borne by the network operator.
Kirjeldus
Bakalaureusetöö
Tehnika ja tehnoloogia õppekaval
Märksõnad
bakalaureusetööd, elektriliinside, võrgumüra, impulsstoiteseadmed, kauglugemine