Transients and Electric Metering

Abstract

The electricity market deregulation or in other words, the need of increased efficiency and customer demands has lead to introduction of automatic reading systems. According to this, there have been thoughts that different kinds of disturbances can possibly cause problems with distance readings of electricity meters. The purpose of this master thesis has been to investigate transients influence on electricity meters and automatic meter reading systems in general and also check if there is a reason to suspect that certain transients can cause reading faults (missing readings or faulty readings), in particular. Mainly, the thesis is dealing with PLC technique based systems but also other types of communications techniques are studied. The thesis also includes getting deeper knowledge about the legislation regulating decisions about introduction of AMR systems in Sweden. Contact with manufacturers of electricity meters and AMR systems has been taken for borrowing necessary equipment. A number of setup configurations have been tested and the transients have been measured in laboratory environment. The aim was to investigate if AMR systems and electricity meters are reliable and properly working with influence from switching transient disturbances. The results from the measurements show that it is not likely that switching transients can cause any change in the readings from electricity meters or value changes in the meter itself, but they have the ability to sometimes block the communication so that the values are not transferred. This can be an important fact depending on how often and how many times the transmission is sent.