Emergency rate-driven control for rotor angle instability in power systems.
Suchithra K S1, Gopalakrishnan E A2, Jürgen Kurths3
1Department of Electrical & Electronics Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore 641112, India.
Chaos (Woodbury, N.Y.)
|July 1, 2022
Summary
This study explores how noise affects power system stability with renewable energy. An emergency control strategy is proposed to maintain stability near operational limits.
Area of Science:
- Power Systems Engineering
- Control Theory
- Applied Mathematics
Background:
- Modern power systems face stability challenges due to the integration of renewable energy sources with inherent stochastic fluctuations.
- Existing power system stability assessments often rely on bifurcation theory but lack coverage of dynamic evolution in non-autonomous, renewable-integrated systems.
- Understanding transitions in these complex systems is crucial for grid reliability.
Purpose of the Study:
- To numerically investigate transition phenomena in a non-autonomous stochastic bi-stable power system oscillator model.
- To analyze the impact of noise on system dynamics and transition characteristics.
- To develop and demonstrate an emergency control strategy for maintaining power system stability.
Main Methods:
- Utilized a non-autonomous stochastic bi-stable power system oscillator model.
- Employed additive white Gaussian noise to simulate stochastic fluctuations.
- Analyzed transition phenomena, focusing on the delay in response to mechanical power variations.
- Implemented and tested an emergency control strategy to preserve stable states.
Main Results:
- Observed significant variations in transition delay due to noise.
- Identified conditions where system response is purely noise-controlled, leading to noise-induced transitions to limit-cycle oscillations.
- Demonstrated that the rate of parameter evolution loses control when angular velocity approaches the noise floor before crossing the unstable manifold.
- Showcased the effectiveness of the emergency control strategy in maintaining stability.
Conclusions:
- Stochastic fluctuations significantly influence transition dynamics in renewable energy-integrated power systems.
- Noise can induce transitions to undesirable oscillations, overriding parameter evolution control.
- An effective emergency control strategy can maintain system stability, enabling reliable operation near physical limits.
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