Renewable Energies


1-Phase and 3-Phase system for domestic  market and central inverter system for industrial market.

Fuel Cell

Electricity generation by converting hydrogen and oxygen into water

Wind Power

3-Phase converter system for wind power electricity generation. AC drivers for yaw, pitch, and auxiliary controls

Inductive components for renewable energies

Inductive components for renewable energies

PRAX has a core competence in inductive components and EMC filters applied in renewable energy inverter.

An inverter is a device that transforms DC voltage coming from photovoltaic panel in an AC voltage and allows providing energy directly to the mains.

Inverter conversion is based on switching topologies at high frequency (from 2 kHz up to 50 kHz). The higher is the output power, the lower is the inverter operating frequency in order to minimize switching losses.

Photovoltaic systems efficiency is a crucial factor. This is determined by the efficiency ratings of the individual elements of solar panel, power inverter and cabling including additional switching elements considered at a certain operating point.

In transformerless solar inverter systems, efficiency is determined to a major degree by the power choke, sinusoidal inductor and EMC filter.

PRAX designs and manufacture capabilities assure high efficiency for such components by means of optimizing the magnetic material as well as the winding structure. It is also important to assure not only high efficiency at full load but also at low power, by optimizing inductor core losses design.

In the case of inverter topologies with galvanic insulation, a power transformer provides for the potential separation. In addition, this electronic circuit variant facilitates, with interaction with a step-up converter, a wide and flexible input voltage range for the chosen generator. PRAX provides efficiency ratings higher than 99% for power transformers in the range of 1kW up to 20kW.

Depending on efficiency, power level, size, weight and cost PRAX offers different magnetic material technology such as Ferrite, Sendust, Iron Powder and Amorphous.

EMC filters for renewable energies

PRAX designs and manufactures EMC filters for PV installations either in DC or AC side. 

DC EMC filters are installed between the PV inverter and solar panel and help to meet EMC directives in grid-connected installations. These filters have been designed to reduce conducted emission towards the solar panel. Such reduction allows longer solar panel installation life-times, as well as increasing immunity in the inverter control phase, avoiding any electromagnetic interference miss function.

 AC EMC filters are installed between the PV inverter output and electrical grid. Their effect is to reduce electromagnetic noise emission from the switched mode inverter to the grid. EMC regulations will be met and problems with electronic devices near the equipment will be avoided.

 AC and DC EMC filters are available up to very high current and voltages (2500A and 760Vac), electrically connected with terminal blocks or bus bars. Low leakage current designs can be provided. These EMC filters are designed and built according EN 60939-2 and UL1283 standards and RoHS directive.

 Although main applications are PV installations, such filters can also be used in other applications where primary energy source is DC, such as fuel cells or batteries. AC EMC filters can be also used in Windmill applications.