Polyphase current measurement with isolated shunt sensors
Shunt sensors are rapidly replacing current transformers as the preferred current sensing solution for electricity meters (e-meters) around the world. Proper design of the current sensing architecture is crucial to achieving the required performance at an acceptable cost. To use shunts in poly-phase systems, it is necessary to isolate the current sensing of each phase. This training session will detail and demonstrate the architectural tradeoffs and solutions for two isolated shunt architectures for e-meters: one architecture using metrology AFEs like the MSP430i20xx and the second architecture using isolated delta-sigma modulators such as the AMC1106 with digital filters. High-side power supply options for powering the isolated shunt sensing devices will also be discussed.