The STSW-STPM004 is embedded in the EVALSTPM-3PHISO evaluation board to implement a complete 3-phase energy meter with low-cost shunt current sensors.
The FW library implements a virtual six-channel STPM3x metrology device with:
- signal acquisition from up to six channels (three phases, each with voltage and current monitoring),
- a processing kernel implementing digital filtering of signals and data processing,
- a set of registers, containing metrology measurements and calibration/configuration data.
The FW exploits the DFSDM filters of the STM32F413RH to convert the six bitstreams into 24-bit voltage and current data, at 200 us rate. All the metrology parameters are computed in real time on a 200 us basis.
The STPM3x-like registers allow the application access to the virtual device (as 3xSTPM32 devices), which can be read/configured by the hardware interface layer.
The FW also implements a virtual com port communication to easily access the internal parameters to read metrology data, to modify the internal configuration for a high flexibility of the application, and to calibrate the board.
Three-phase metrology FW for STPMS2 sigma-delta modulator
Implements hardware access layer to STPMS2 devices for signal acquisition of up to six channels (three-phases, each with voltage and current monitoring) @200 us
Processing kernel implementing digital filtering of signals and data processing
Provided full set of metrology registers, containing metrology measurements and calibration/configuration data
Basic metrology application for a three-phase meter with scalable topology
Active wideband, active fundamental, reactive and apparent power/energy calculation for each phase and cumulative
Voltage and current channels decimated samples available
2.5 kHz measurement bandwidth
RMS and THD (optional) calculation of each voltage and current signal
Selectable high-pass filter for DC measurement
Line period and phase shift measurement for each phase
Phase voltage delays
USB communication available through virtual com port mode