Improved Broadband Harmonic Filter Design for Adjustable Speed Drives

In this paper an analytical design method of the improved broadband passive harmonic filter (IBF) for three phase diode rectifier front-end type adjustable speed drives is presented. The method is based on frequency domain modeling of the system. The success of the method involves accurate representation of the load harmonics. The optimal filter design yields high input and output power quality while keeping the filter size small and avoiding harmonic resonance problems. The paper illustrates the superior performance characteristics of IBF by means of computer simulations and laboratory experiments