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24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3660-3663, A new measurement technology for automated long term measurement evaluations of photovoltaic (PV) modules has been invented by IWES. The measuring card ISET-mpp meter (Figure 1) not only allows the measurement of the main module parameters but also enables the complete I-V characteristics of the modules to be measured. Especially for newly developed modules this approach offers great potential for performance-tests, derivation of model parameters and new model equations. By using standardized communication commands it is possible to include the measuring board in a data acquisition system. Thus long-term measurements of PV modules in different operating modes and in different environments become possible. The I-V curves of the modules can be determined at specified intervals, or initiated by a trigger signal. Hereby for example, the influence of various weather conditions and shadowing situations to the module performance can be assessed. The measurement results can be sent via a serial port to a PC for further data processing.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3695-3698, Every PV inverter and electricity meter available on the market is tested according to the standards which are valid for the individual product. Nevertheless, malfunctions of some electronic electricity meters have been detected, when used in conjunction with special PV inverters. In one case, the meter displayed only 85% of the real energy fed into the public grid by the PV inverter [1]. The meter was checked in a calibration laboratory without negative results. Investigations by ISET have shown that the RF ripple current of the inverter influenced the meter. In most inverters, the frequency of the ripple current lies between 3 kHz and 150 kHz. Unfortunately, no emission and immunity requirements exist for inverters and meters within this frequency range [2] [3] [4]. ISET/IWES has developed a special test setup, which can simulate electric ripple currents, similar to those generated by inverters. Investigations on inverter EMC test setups with low differential mode impedance AC artificial mains networks (AMN) are in progress.