A Low-Cost Approach to the Skin Effect Compensation in Cylindrical Shunts

In this paper the development of a new design solution for high-current shunt resistors is presented, which allows achieving very good accuracy while requiring a simple and low-cost manufacturing process. It is based on a solid cylinder having the voltage measurement circuit which runs through two holes drilled in the cylinder itself. Starting from the well-known expression of the current density in a cylindrical conductor, the frequency response of the shunt is obtained in closed form as a function of the geometric parameters. In turn, the positions of the voltage measurement terminals are chosen by optimizing the frequency response function over a specified range. A shunt prototype has been manufactured and its measurement performance has been evaluated. The experimental results confirm the validity of the approach and highlight the significant improvement with respect to the single-hole cylindrical shunt which has been recently proposed by the authors. The obtained measurement accuracy is noticeable when compared with the ease of manufacturing

Low peak derivative sum of sines

This paper proposes a method to generate multisines signals with reduced peak derivative. This is done by adjusting the phases in the Fourier domain with Genetic Algorithm such that in the time domain the maximum absolute signal's derivative is minimized. The performance evaluation is made by comparing the method to signals with the same spectrum but with phase adjusted randomly. It will be shown for an audio test signal case study of a multisines signal comprising 2500 sines that a reduction of 42% with respect to the mean maximum peak derivative and 31% with respect to the minimum maximum peak derivative over 1 million random trials. The proposed method is contrasted with a low crest factor signal method. It is found that there is a positive correlation between peak amplitude and peak derivative when signals are generated with random phases. Moreover, the signals obtained by minimizing either the peak amplitude of the peak derivative had also good performances with respect to the non-optimized criterion