Precision is measurable The use of renewable energies reveal specific requirements for electricity meters
Precision is measurable General Meter testing reasons for incorrect operation
Precision is measurable PTB Topic of ZMP 2011: 2 kHz kHz 3
Precision is measurable Meter testing / Reasons for incorrect operation How currents outside of the 50 Hz frequency range arise? Why are some electricity meters get disturbed by a frequency from 2 kHz? What type of meter is to be selected for which electricity consumers? How can ensure the correct function of the meter? How can you check the meter installation, easy, safty and fast? 4
Precision is measurable How currents outside of the 50 Hz frequency range arise? Example: switched-mode power supply 5 Circuit diagram of a switched-mode power supply Voltage- and Currentcurve
Precision is measurable How currents outside of the 50 Hz frequency range arise? Example: switched-mode power supply Fourier Transformation 6 Current profile of a switched-mode power supply 80% 150-Hz-Anteile 50% 250-Hz-Anteile 22% 350-Hz-Anteile Fourier Transformation for I Netz:
Precision is measurable 7 householdindustry photovoltaic plants block heating station (Dachs Stirling)wind engine Energy saving lampTemperaturgeregelte Heizungen und Öfen Computer, Audio- and Video deviceswelding machine Dimmerelevator Induction cookerDynamic reactive-power compensation systems freezerelectronic frequency converter How currents outside of the 50 Hz frequency range arise? Examples
Precision is measurable Why are some electricity meters get disturbed by a frequency from 2 kHz? harmonic = 40 x 50 Hz = 2 kHz EN und EN The frequency range from 2-9 kHz is in Europ curenntly not regulatet in the EMV Norm.
Precision is measurable Jan What type of meter is to be selected for which electricity consumers? Production:Installation of highly accurate meters and measuring transformers in power plants Transmission: Transfer stations between different networks Customers: Installation of meters and measuring transformers on the consumer’s premises Production Customers Transmission
Precision is measurable What type of meter is to be selected for which electricity consumers? The solar electricity-magazine PHOTON reported in the November 2010 edition already, that some electronic power meter are to slow … … Some inverters are not compatible with electronic energy meters. Who is using the wrong combination of devices must be feared that his input meter shows too little income. The problem is known in professional circles for at least three years, some Operators even have blacklists Frank Greizer SMA Solar Technology AG (Bereichsleiter Technologieentwicklung) … be seen from any point of any failure or fault of SMA and see the buck at the meter manufacturers … Karsten Peterson Itron Zähler& Systemtechnik GmbH (Vertriebsleiter Deutschland) … by the inverter generates extra power and pollution would have to actually work to avoid these … Typ Iskra MT171 shows up to 20% less
Precision is measurable What type of meter is selected for electricity consumer? The VDE-project team „ Measurement reliability and stability of electricity meters and accessories“ has conducted studies on this topic. In the laboratory of the VDE Testing and Certification Institute, 12 electronic electricity meters has been tested. It has been determined error of over 70%. (graphic left) In the following customers are high-frequencys expected : Solar inverter systems Wind turbines pumping stations commercial operation / metal working 11
Precision is measurable Type testing and standards norms EN X (for electronic electricity meters) will soon be expanded and standardized. At customer site with high frequency system size it is possible to check the meter with the real system size on site with appropriate measuring instruments More possible disturbances:DC, DC voltage, stress peaks modulated frequency changes( Flicker) overburden of Current- and Voltagetransformer transport damage of the meter connection erros during the installation of the meter 12 How ensure the correct work of the meter?
Precision is measurable On site test Collection of network variables Connection check Error measurement logging 13
ZERA stands for innovation, flexibility and sustainability Precision is measurable 14
ZERA stands for innovation, flexibility and sustainability Precision is measurable 15 Thank you for your attention Matthias Heinzen Sales Manager ZERA GmbH Hauptstrasse 392 D Koenigswinter