End User:

Energy Company in Pakistan (Confidential)

Project Scope

Supply, installation, testing, and commissioning of a PLC-SCADA system for an automatic turbine governor control to modernize the power plant.

Background:

A hydroelectric power plant equipped with a generator unit has a capacity of 2.5 MW. The power output generated is 11 kV at 50 Hz, which is locally connected to the 33kV substation. The existing PLC system had failed, causing the generator to operate on a relay logic-based manual control system. The speed governing the hydraulic system and the brushless excitation system, including the Automatic Voltage Regulator (AVR) and protection system, were also functioning manually.

System Description:Automatic Turbine Governor

Due to limitations in the turbine control and machine protection systems, the existing system was replaced with a highly reliable and rugged automation system. The entire hydroelectric generation system is now controlled and monitored by a centralized Programmable Logic Controller (PLC) with a Local Human-Machine Interface (HMI) and Supervisory Control and Data Acquisition (SCADA) system.

Integration Details:

The following systems are integrated with the PLC for machine protection and control:

• Cooling Water Distribution System: Ensures optimal cooling of the generator and associated components.
• Hydraulic Speed Governor System: Provides precise control over the turbine speed.
• Transformer AVR (Automatic Voltage Regulator): Maintains consistent voltage levels and protects against voltage fluctuations.

The following components are incorporated as part of the control and protection system inside the control panel:

• Generator Protection Relay: Protects the generator from faults and irregular conditions.
• Ground Fault Protection Relay: Detects and isolates ground faults to prevent damage.
• Synchronous Motors: Ensures the synchronous operation of the generator.

Benefits and Results:

With the implementation of the new PLC-SCADA system, the hydroelectric plant has been transformed into a state-of-the-art facility. Key benefits include:

• Enhanced Automation: The entire system is automated, reducing the need for manual intervention and improving operational efficiency.
• Improved Reliability: The robust PLC-SCADA system ensures reliable operation and quick response to any faults or irregular conditions.
• Advanced Monitoring and Control: Real-time data monitoring and control through the centralized HMI and SCADA provide better oversight and management of the power generation process.
• Increased Safety: Integration of protection relays and advanced control systems enhances the safety and longevity of the plant equipment.

The upgraded system has significantly improved the plant’s operational efficiency and reliability, positioning the energy company at the forefront of modern hydroelectric power generation technology.