Very Efficient Current Observer for Sigma Delta Modulation based Current Transducers for High Bandwidth Current Control

Instead of analog current transducers in combination with successive-approximation analog-to-digital converters sigma-delta technology jointly with digital decimation filter technology is increasingly used. The article describes a new technique how the bit-stream can be formed into a quasi-time-continuous measured value in a very efficient way and similar to a classical observer structure. The laboratory test results are based on an FPGA implementation.