6.2.4 Task Scheduler

The Timer/Counter Type A (TCA1) schedules the task for every 500 μs to execute the below functionalities:

• Measure the emulator three-phase signal
• V_rms calculation
• Phase loss detection
• Phase reversal detection
• Bind and generate the data array, as per the data stream protocol

In the application, the data visualizer is used for displaying the three-phase AC signal graphical view, measured RMS data, and Fault status. The three phases (L1, L2, and L3) of emulated three-phase signal are fed as input to the ADC peripheral. The converted digital data is transmitted to the data visualizer over a USB-UART interface, to reproduce the emulated three-phase signal on data visualizer.

The data streamer array consists of instantaneous digital values of the three-phase emulated signal, RMS voltage level, frequency measured, and fault status. The application output data is appended into the end of data streamer data array, according to Atmel data streamer protocol.

The user can send commands from the data visualizer to demonstrate features of the three-phase Sequence detector. The microcontroller receives user commands from the data visualizer through a USB-UART interface for changing amplitude (to demonstrate phase loss) and phase (to demonstrate phase reversal) of the three-phase signal in run time.