REO HF components and chokes Available with iron cores at smaller power ratings. Also available as REO PowerUnit I (series combination) with different hf components for use in inverters with power ratings up to 10 kW.
The design of the PowerUnit I allows optimum cooling (also in case of limited space) REO PFC Chokes (CHI 412) for limitation of mains harmonics of non-linear loads on the AC mains supply REO HF transformer (HPTB) for high performance switching power supplies in half or full wave switching topologies and resonant designs REO HF Storage choke (CHI 213) for storage and discharge of magnetic energy with different core materials:
A LCL filter is often used to interconnect an inverter to the utility grid in order to filter the harmonics produced by the inverter.
Voltage source inverters (VSI) are used for energy conversion from a DC source to an AC output, both in a stand-alone mode or when connected to the utility grid. A filter is required between a VSI and the grid, imposing a current-like performance for feedback control and reducing harmonics of the output current. A simple series inductor can be used, but the harmonic attenuation is not very pronounced. In addition, a high voltage drop is produced and the inductor required in the design is very bulky.
Commonly a high-order LCL filter has been used in place of the conventional L-filter for smoothing the output currents from a VSI [1], [2]. The LCL filter achieves a higher attenuation along with cost savings, given the overall weight and size reduction of the components. LCL filters have been used in grid-connected inverters and pulse-width modulated active rectifiers [1]-[3], because they minimize the amount of current distortion injected into the utility grid [4]. Good performance can be obtained in the range of power levels up to hundreds of kW, with the use of small values of inductors and capacitors [3]. The higher harmonic attenuation of the LCL filter allows the use of lower switching frequencies to meet harmonic constraints as defined by standards.