This reference design demonstrates the working of various functional blocks of an automatic power factor controller (PFC) used in MV/LV electrical distribution. This includes accurate measurement and computation of voltages, currents, power and power factor, display of measured parameters using four-digit seven-segment display, alarms and status indication using LEDs, switching outputs for driving contactor or thyristor for switching capacitor banks and monitoring of local and remote temperature using a breadth of products from our portfolio.
Features
- Accurate measurement of 3-Φ voltage, current (simultaneous sampling), power, power factor accuracy < 0.5% achieved using 24-b ΔΣ ADC
- Seven segment (SS) LED – two constant current drivers are cascaded to drive four digit SS LED display with decimal point
- Relay/ transistor output switching – options for controlling contactor and thyristor is provided.
- 3 channels (expandable to 7) is dedicated for controlling relay output (contactors)
- 2 channels (expandable to 4) with isolation for controlling transistor output (thyristors)
- Status indication – 16 LEDs are controlled using a constant-current LED sink driver.
- Sensors for temperature and light sensing are included.