Passive Power Filters

TL;DR

This paper introduces three different passive low-pass filter structures for d.c./d.c. power converters with inductive loads, providing formulas, practical examples, and comparisons to guide effective voltage ripple reduction.

Contribution

It presents new filter structures specifically designed for high-current power converters, with detailed formulas and practical insights for implementation.

Findings

Comparison of three filter structures based on practical examples

Formulas for calculating filter components are derived step-by-step

Discussion of practical aspects for realizing power filters

Abstract

Power converters require passive low-pass filters which are capable of reducing voltage ripples effectively. In contrast to signal filters, the components of power filters must carry large currents or withstand large voltages, respectively. In this paper, three different suitable filter structures for d.c./d.c. power converters with inductive load are introduced. The formulas needed to calculate the filter components are derived step by step and practical examples are given. The behaviour of the three discussed filters is compared by means of the examples. Practical aspects for the realization of power filters are also discussed.