Power System Reliability Studies & Simulations at Tenaga Nasional Berhad

The company

Tenaga Nasional Berhad (TNB) is the Malaysian multinational electricity company and the only electric utility in Peninsular Malaysia. TNB Research (TNBR) serves as the in-house solution provider—a centralized, one-stop center for technical solutions and innovation. Backed by years of experience, TNBR specializes in power system reliability and efficiency through advanced studies and simulations, delivering outcomes that help TNB maintain a resilient, reliable, high-quality power grid.

The Challenges

• Large-Scale Network Simulation: TNB needed a real-time simulator capable of emulating the actual dynamic response of its large-scale power system network during interaction with protection systems.
• Complex SPS Development: Increasing levels of complexity in Special Protection Scheme requirements made traditional system-level testing approaches insufficient and costly.
• Pre-Deployment Validation: Complex protection systems designed to mitigate system-wide disturbances required comprehensive closed-loop testing in a controlled environment before deployment to the actual grid.
• Cost-Effective Computing: Simulating thousands of buses and generators in real time demanded a platform that could achieve high-speed execution without requiring excessive computing resources.

The OPAL-RT Solution

TNB implemented a comprehensive HIL testing platform for SPS validation using OPAL-RT’s phasor-domain simulation:

• ePHASORSIM Solver: Selected over other HIL simulators for its ability to vary simulation time-step duration—enabling large-scale power system simulation with reduced computing power while maintaining accuracy. Operating at a 10 ms time-step, it provides phasor voltage and current information for real-time grid emulation.
• RT-LAB & OP5600: The real-time simulation software and hardware platform enables model-based design that interacts with real-world environments, running MATLAB/Simulink models in real time.
• Complete HIL Infrastructure: The platform integrates analog signal amplifiers, SPS hardware (RTAP controllers), a PI Server for data archiving, GPS clock synchronization, WAMS applications, and physical IEDs connected via Ethernet—replicating TNB’s operational SPS architecture of 190 IEDs and 25 RTAPs.

The results

The HIL platform was validated with a full 1,100-bus TNB grid model as a case study:

• Full-Scale Grid Simulation: Successfully simulated the complete 1,100-bus TNB power system in real time, verifying the platform’s effectiveness for system-level SPS testing.
• Comprehensive Contingency Testing: Engineers can now test SPS systems under various grid conditions and contingencies in a controlled, repeatable environment.
• Faster Issue Detection: Significantly reduced the time required to detect design issues, lowering the risk of design errors or hidden failures.
• Increased Confidence: Enhanced statistical confidence in the protection system’s reliability before field deployment.
• Cost Reduction: ePHASORSIM’s phasor-domain approach reduced real-time simulator costs compared to full EMT-type simulations, while still capturing all relevant transient phenomena for SPS applications.

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