Input filter design for PWM current-source rectifiers

Pulse width modulated (PWM) rectifiers allow the elimination of low order harmonics. Filtering requirements for PWM current-source rectifiers are usually satisfied through the use of low-pass LC input filters. The design of LC filters involves the positioning of the resonant frequency to meet the harmonic attenuation requirements (THD), and the introduction of damping at the resonant frequency to avoid amplification of residual harmonics. The systematic approach proposed is focused on PWM rectifiers but can be extended to other classes of converters. Practical design considerations are detailed and design equations are derived. Simulated results are presented to validate the design approach.<>