Power Monitoring
Beckhoff offers various terminals for implementing power grid analysis and monitoring in its I/O portfolio. In a single- or three-phase grid, power measurement terminals such as the EL3403 or EL3413 directly provide RMS values for current and voltage, as well as active, reactive and apparent power. The EL3773 and EL3783 power monitoring terminals can also be used to log the raw data for current and voltage, so that grid events can be detected even more accurately, and various values can be calculated in the controller itself.
The TwinCAT 3 Power Monitoring Function is a PLC library for evaluating raw current and voltage data provided by the power monitoring terminals.
The library provides function blocks for calculating RMS values for current, voltage and power. These can be output as instantaneous or average values. The function block also offers maximum and minimum values. Frequency and frequency spectra can be determined, such as e.g., harmonics in the grid and their load in the form of the Total Harmonic Distortion (THD). Furthermore, the library offers function blocks which can be used to determine frequencies and rotary fields.
General algorithms
Algorithm | Description | PLC function block |
|---|---|---|
Scaling of the input data for current and voltage | FB_PMA_Scaling | |
Scaling of the input data of current and voltage provided as inputs by EL3773 EtherCAT Terminals. | FB_PMA_Scaling_EL3773 | |
Scaling of the input data of current and voltage provided as inputs by EL3783 EtherCAT Terminals. | FB_PMA_Scaling_EL3783 |
Single-phase algorithms
Algorithm | Description | PLC function block |
|---|---|---|
Calculation of the base frequency of the input signal. | FB_PMA_Frequency_Period_1Ph | |
Calculation of analysis values for the signal curve of current and voltage over time. | FB_PMA_BasicValues_Period_1Ph | |
Calculation of characteristic power values of the connected loads based on the signal period. | FB_PMA_PowerValues_Period_1Ph | |
Calculation of the harmonics of current and voltage based on the signal period. | FB_PMA_Harmonics_Period_1Ph | |
Calculation of the magnitude spectra of the current and voltage values. | FB_PMA_Spectrum_1Ph | |
Calculation of the magnitude spectra of the current and voltage values. In addition, p-quantiles of the spectrum distribution can be calculated. | FB_PMA_Spectrum_Quantiles_1Ph | |
Calculation of power characteristics of the connected loads based on calculations in the frequency range. | FB_PMA_PowerValues_1Ph | |
Calculation of harmonics of current and voltage. | FB_PMA_Harmonics_1Ph |
Three-phase algorithms
Algorithm | Description | PLC function block |
|---|---|---|
Calculation of the base frequency of the input signal. | FB_PMA_Frequency_Period_3Ph | |
Calculation of analysis values for the signal curve of current and voltage over time. | FB_PMA_BasicValues_Period_3Ph | |
Calculation of characteristic power values of the connected loads based on the signal period. | FB_PMA_PowerValues_Period_3Ph | |
Calculation of the harmonics of current and voltage based on the signal period. | FB_PMA_Harmonics_Period_3Ph | |
Calculation of the magnitude spectra of the current and voltage values. | FB_PMA_Spectrum_3Ph | |
Calculation of the magnitude spectra of the current and voltage values. In addition, p-quantiles of the spectrum distribution can be calculated. | FB_PMA_Spectrum_Quantiles_3Ph | |
Calculation of power characteristics of the connected loads based on calculations in the frequency range. | FB_PMA_PowerValues_3Ph | |
Calculation of harmonics of current and voltage. | FB_PMA_Harmonics_3Ph |