Design and analysis of a hybrid power system for remote natural gas pipeline control stations

The most efficient way to transport natural gas from its source to its destination is through a pipeline network. The efficient operation of natural gas pipeline control stations relies on electrical equipment such as data loggers, control systems, surveillance and communication devices, etc. These stations are strategically located in remote areas, making it challenging to maintain a reliable and continuous power supply. As a result, non-renewable energy sources like natural gas and diesel are typically used for power generation due to the lack of reliable electrical infrastructure. This thesis offers a comprehensive solution to replace high-cost energy sources with a cost-effective and environmentally friendly alternative for remotely located natural gas pipeline control stations. The first step involves designing a hybrid power system (HPS) using HOMER Pro software to address the unique needs of a remote natural gas pipeline control station in Pakistan as a case study. A detailed analysis of capital and energy costs shows that the proposed system is cost-effective compared to the existing setup. The design is validated through dynamic modeling in MATLAB/Simulink R2022 and experimental validation is conducted using hardware in the loop (HIL) and OPAL-RT Technologies’ real-time OP5707XG simulator. The second step involves assessing the output power quality of the designed hybrid power system. Since inverters play a critical role in hybrid power systems, their impact on output power is significant. Various multilevel inverter topologies are analyzed and compared with a conventional two-level inverter. Simulations are performed in MATLAB/Simulink, showing that increasing output voltage levels approximates a sinusoidal waveform, reducing Total Harmonic Distortion (THD) and improving power quality. The experimental validation of the nine-level cascaded H-bridge Multilevel Inverter (MLI) is conducted using Hardware-in-the-Loop (HIL) with OPAL-RT Technologies’ real-time OP5707XG simulator. Finally, in the third and last step, an Internet of Things (IoT)-based, open- source SCADA architecture is designed to monitor the designed hybrid power system, addressing the limitations of existing proprietary and non-configurable SCADA architectures. The proposed system includes voltage and current sensors for data collection, an ESP32-WROOM-32E microcontroller as the Remote Terminal Unit (RTU) for processing, a Blynk IoT-based cloud server serving as the Master Terminal Unit (MTU) for data storage and human-machine interaction (HMI), and a GSM SIM800L module with a local Wi-Fi router for communication between the RTU and MTU. The proposed system exhibited a low power consumption of 3.9 W and incurred an overall cost of 40.1 CAD making it an extremely cost-effective solution for remote natural gas pipeline control stations.