Genetic-algorithm-based design of passive filters for offshore applications

Abstract

With the proliferation of power electronics converters and increased use of magnetics, power lines have become highly polluted. Both passive and active filters have been used near harmonic-producing loads or at the point of common coupling to mitigate/block current harmonics. Shunt filters still dominate the harmonic compensation at medium/high voltage level, whereas active filters have been proclaimed for low/medium voltage ratings. With diverse applications involving reactive power together with harmonic compensation, passive filters are found suitable. For offshore platforms, having multiple variable frequency drives for oil exploration and the power fed through submerged power cable reduces the reactive power requirement in the power system. Under such reduced reactive power requirement, the design of passive filter conforming to the IEEE 1531 standard is presented in this paper. This paper utilizes genetic algorithm technique to design the tuned harmonic filters to compensate current harmonics together with limited reactive power compensation. The main idea behind the design is minimization of net source rms current with insertion of a passive filter. The formulation thus becomes a combinational optimization system with nondifferentiable objective function. Other environmental and operational constraints are also incorporated in the design technique to ensure their effective performance. The performance and operation of the so-designed passive filter has been studied through simulation under MATLAB environment.