Growatt has become one of the few Asian inverter brands to receive the certification in accordance with Medium Voltage Directive of the German Federal Association for Energy and Water (Bundesverband der Energie- und Wasserwirtschaft in German, BDEW). Few Asian inverter brands have got the expertise and capability to comply with the BDEW directive, which requires high standard of functionalities of all generating units. This awarded certification marks a solid step by Growatt for business development of the medium and large scale application in Europe.
As photovoltaic plants develop, more and more electricity producers connect their system to the grid and the ability of production unit to adapt to the grid fluctuations becomes increasingly imperative. Formulated by BDEW, the Directive requires lots of functionalities of the inverter including limitation of the fed-in active power in case of overload, active power reduction in case of overfrequency, dynamic grid support in case of LVRT, reactive power capability etc.
Based on the measurements of power generating unit characteristics, a group of Growatt engineers set out on their own and has successfully built a simulation model to certify the power generating unit, in this case Growatt MAX, complies with the BDEW directive’s requirements.
BDEW has strict requirements of the PQ capability of inverter and it is mandatory for the inverter to operate at full output with 0.95-1.1U, which has great impact on heat dissipation performance of the inverter and thus requires a higher standard of it. That is one of the reasons why few Asian brand inverters could succeed in passing the test.
BDEW requires PF deviation to stay within ±0.005 when the inverter is doing the reactive power control, which is a much higher standard than CEI's ±0.01 requirement. Additionally, the reactive power should increase at a specific slope curve. The voltage deviation should be ±1% for its over/under voltage test and frequency deviation ±0.01Hz for its over/under frequency test. And the trip time deviation should be ±100ms. The total testing conditions reach over 16 types and the testing period takes more than three times of VDE0126.
With the continuous efforts of engineers and the excellent performance of MAX, once and for all Growatt MAX products were successfully tested and certified according to the BDEW’s technical guidelines. Growatt MAX comes with a powerful quad-core architecture, which greatly enhances its capability to process the information or instructions more quickly and handle all kinds of tasks more efficiently including monitoring, protection, smart diagnosis etc.