Extended Current and Voltage Measurement Using Shunts for Protection Relays Reference Design
TIDA-00738
This product has been released to the market and is available for purchase. For some products, newer alternatives may be available.
This product has been released to the market and is available for purchase. For some products, newer alternatives may be available.
See the Important Notice and Disclaimer covering reference designs and other TI resources.
Key Document
- Wide Input Current Using Shunts and Voltage Measurement for Protection Relays
(PDF 4140 KB)
04 Dec 2015
Description
The TIDA-00738 TI design demonstrates a unique approach for extending the current measurement range using a single shunt and voltage measurement using AMC1304Mx5 Isolated Delta-Sigma (ΔΣ) modulator. With careful selection of a low value shunt resistor that minimizes power dissipation, a front end amplifier with low noise and by introducing two gain paths, both upper and lower current limit is extended. Accuracy of < ±0.5 % for both current and voltage measurement is achieved by interfacing the modulator output to AM437x host processor which performs the Sinc3 filtering.
Features
- Single Phase voltage and current measurement (shunt based) using isolated delta-sigma modulator (AMC1304Mx5)
- Measurement accuracy:
- AC Current: < ± 0.5% from 0.1A to 40A (or 60A) for In = 1A
- AC Voltage: < ± 0.5% from 10V to 300V
- AFE interfaced to host MCU (AM437x Sitara™ ARM® Cortex®-A9 Processor) which performs Sinc3 digital filtering using PRU-ICSS
- Onboard isolated ± 2.5V and +5.0V Power supply for AMC1304Mx5 and OPA188 using Transformer Driver and LDOs
- Designed to work from 0.1A to 60A (In=1A) and can be extended for wider range (In=5A) by changing Shunt and Gain values.
See the Important Notice and Disclaimer covering reference designs and other TI resources.
