Grid infrastructure solutions on show at DistribuTECH 2015

DistribuTECH attendees can experience TI’s AFE for merging units and multi-function protection relays demonstration. This solution addresses the front-end needs of merging units requiring measurement of multiple current and voltage channels. This implementation is modular, allowing easy expansion of channels while keeping the connectivity to the processor minimal by using the SPI daisy chain feature. All of this is made available in the 16-bit, 8-channel, 500kS/S ADS8688 SAR ADC which offers a high level of integration. The ADS8688 includes high-voltage attenuation and level-shift circuitry for each channel and an integrated voltage reference with low temperature drift. In this solution, when two ADCs are connected in daisy chain mode, simultaneous sampling is also possible. Additionally, engineers can use the ADS8688 for broad protection and monitoring applications in generation, transmission and distribution of energy of the smart grid.

Attendees can also see the company demonstrate its isolated shunt-based current measurement. This design enables high accuracy current measurement without the need to use isolated current sensors such as current transformers. Analogue signal isolation is achieved through the use of TI’s AMC1304 delta-sigma modulator, which incorporates reinforced high-voltage isolation, as well as a high precision modulation. This solution uses shunt sensors, which help designers decrease board size, reduce product weight and cost, mitigate cross talk and EMI in their system and eliminate the need for extensive calibration algorithms. Additionally, the AMC1304-based solution potentially increases product life through lower mechanical issues by using shunt current sensors.