Isolated shunt current measurement reference design with independent digital filter

This reference design utilizes an isolated modulator and independent digital filter to implement a Class 0.5 three-phase power measurement system with an isolated shunt sensor, eliminating the need for an integrated synchronization filter and allowing an optional host microcontroller (MCU). ) will be broader in scope. In this design, the current sensed by the isolated modulator and the phase voltage sensed by the host microcontroller are synchronized; more advanced metering algorithms are supported using the Simplelink™ ARM Cortex M4 host MCU. This design protects against magnetic tampering attacks by using current sensors and a power supply that does not use any transformers or other magnetic components. This subsystem design has been tested and includes hardware.

characteristic

• ● Category 0.5 three-phase metering with galvanically isolated (up to 600VRMS, peak isolation voltage 4kVRMS) shunt sensors
• ● Electrically isolated shunt sensor and capacitive voltage drop power supply provide immunity to magnetic field interference
• ● Standalone digital filter enables use of host microcontroller without digital filter, thus increasing design portability
• ● Synchronous voltage and current sampling across all phases and the ARM® Cortex® M4 host MCU enable the addition of advanced metering algorithms
• ● Active and reactive energy, root mean square (RMS) current and voltage, power factor and line frequency calculations