Precision digital filters for high voltage impulse measurement systems

This paper reports the design, testing and practical applications of two ty pes of high order FIR digital filters Tor noise reduction and data smoothin g of high voltage impulse waveforms. Particular attention is paid to the es timation of the error limits introduced by the digital filters. The error e stimation involves the analysis of the frequency components of the impulse waveforms, the ripple calculation of the filters and testing of the filters with simulated and real impulse waveforms. The relationships between the f ilter parameters and the required filter accuracies are established.