MW Hydropower Plant (Unit M1): Power System Stability Analysis with PSS Implementation

This example features a 1000 MW hydropower plant (Unit M1) connected to a load center through a 500 kV, 700 km transmission line. The load center is modeled as a 5000 MW impedance load, supplied by both the remote 1000 MW generation source and a local 5000 MW power station (Unit M2). The system is initialized with 950 MW power transmission through the line, closely approaching its surge impedance loading (SIL = 977 MW). Both generating units are configured with equivalent Hydro-Turbine Governor (HTG) systems, excitation control systems, and Power System Stabilizers (PSS), all implemented within the "Turbine and Governing" subsystem. The controller implementation includes transfer function blocks for PSS algorithms, typically employing lead-lag compensators to damp low-frequency oscillations.

Through this model, we simulate fault conditions in the 500 kV system to observe PSS effectiveness in maintaining stability. The analysis provides detailed information on fault characteristics (e.g., three-phase symmetrical faults), PSS response time measurements, control methodologies (including anti-windup protection), and stability improvement strategies. The simulation allows parameter tuning through MATLAB/Simulink blocks such as PID controllers and transfer function modules to optimize damping performance. Additional scenarios can be explored by modifying machine configuration parameters or introducing new control modules like supplementary damping controllers.

In summary, this example provides fundamental understanding of power system dynamics and offers practical approaches for enhancing stability through control system implementation. The model serves as a template for testing advanced PSS algorithms, including adaptive controllers or neural network-based stabilizers, using Simulink's Power Systems toolbox for real-time simulation and analysis.