Design of New Harmonic Filter for Renewable Energy Source: Review

Optimal design of passive filter (combination of L, C & R) for grid connected inverter system is studied. For that, initially normal design is considered. Higher order passive filters are essential in meeting the interconnection standard requirement for grid-connected voltage source converters. The IEEE 1547-2008 specifications for high-frequency current ripple are used as a major constraint early in the design to ensure that all subsequent optimizations are still compliant with the standards. The choice of switching frequency for pulse width modulation single-phase inverters, such as those used in grid-connected photovoltaic application, is usually a trade-off between reducing the total harmonic distortion (THD) and reducing the switching loss. The total inductance per unit of the passive filter is varied, and filter parameter (L, C & R) values which give the highest efficiency while simultaneously meeting the stringent standard requirements are identified. Then the conduction and switching losses that are caused by the filter are calculated and are optimized considering the level of reduction of harmonics. Hence the main aim of the study is to attenuate higher order harmonics along with the reduction in switching losses to ensure sinusoidal current injection into the grid. Further, the different switching schemes for single phase full bridge inverter are studied and compared to get the switching scheme which gives lesser switching losses. Proposed filter will be design for optimal inductance and capacitance values are obtained. Stability Analysis of Grid-Connected Inverters with proposed Filter Considering Grid Impedance expected more stable than available work. Simulation will be done on MATLAB SIMULINK environment for feasibility of the study in near future.