Project Scope

Design, engineering, manufacturing, supply, and commissioning of String Combiner Boxes, Weather Station, Data Acquisition Panels, and a SCADA (Supervisory Control and Data Acquisition) system for a 1 MWp (Megawatt Peak) ground-mounted solar PV (Photovoltaic) plant.

Background

In line with the Government of Pakistan’s initiative to achieve 100 MW of solar power, a 1 MW solar PV plant was set up. Through competitive bidding, FAIZAL was awarded the SCADA scope of works to monitor and regulate the 1 MWp grid-tie solar power plant. The requirement was to provide an online monitoring system that offers information on the instantaneous output energy and cumulative energy of the inverters, meters, breakers, and weather stations.

System Description

The integrated SCADA system deployed communicates with all inverters, PCUs (Power Conditioning Units), String Combiner Boxes, weather stations, meters, and breakers of the 1 MWp solar power plant. The SCADA system provides information on both instantaneous energy and cumulative energy for each of the inverters.

The Data Acquisition system measures and logs the following parameters:

• Ambient Air Temperature
• Control Room Temperature
• Module Temperature
• Wind Speed
• Solar Irradiation
• Inverter Output
• DC Output
• AC & DC Power of Inverter
• Energy Delivered to the Grid
• System Frequency
• Voltage of the HT (High Tension) and LT (Low Tension) Side
• Current and Voltage of each Sub Array
• Power at the 11 kV Terminal

SMB (String Monitoring Box): This is a device used in solar power systems to monitor the performance of individual strings of solar panels. It helps in detecting any issues such as underperformance or faults in the solar strings, allowing for prompt maintenance and efficient operation of the solar PV plant.

The SCADA system stores daily, monthly, and yearly energy generation data, providing the Performance Ratio (PR) of the plant. All events and outages are recorded with date and time stamps. The proposed SCADA system can control and monitor the entire power plant according to the IEC 61850 (International Electrotechnical Commission) communication protocol.

Additionally, the system includes String Combiner Boxes with monitoring features. A 24-channel String Monitoring unit helps the customer monitor string-level current and voltage. These String Monitoring Boxes are integrated into the SCADA system over the Modbus RTU (Remote Terminal Unit) protocol.

Result

• Comprehensive Data Storage and Visualization: The SCADA system stores and displays data and trends in graphical and tabular forms, including daily, monthly, and annual energy production by the plant.
• Complete Plant Visibility: The system provides complete visibility of the 1 MWp solar PV plant by monitoring net meters, LT meters, inverters, string monitoring boxes, weather stations, ACB (Air Circuit Breaker), VCB (Vacuum Circuit Breaker), transformers, and more.

This comprehensive SCADA-based monitoring solution ensures optimal performance and efficient management of the solar PV plant, aligning with the government’s solar power initiatives and promoting sustainable energy practices.