Comparison of classical methods for tuning automatic regulators of nuclear power plants and the method using an analytical simulator of nuclear power plants

Objective. The article presents an innovative approach to optimizing the parameters of automatic regulators for nuclear power plant units using high-precision analytical simulators. The study addresses a key challenge in modern power engineering - improving the efficiency and reliability of automatic control systems while reducing commissioning timelines.
Method. Unlike traditional Cohen-Coon and Skogestad methods based on simplified models, the proposed methodology employs comprehensive mathematical models that accurately reproduce physical processes in actual equipment. The experimental part of the research was conducted on the specialized UMICON software-hardware complex, simulating power unit operation with various dynamic characteristics. A first-order system with parameters K=1, τ=7 s, θ=0.3 s served as the test object, enabling statistically significant results with 0.95 confidence probability. Particular attention was given to model verification and testing solution stability across a wide range of operating modes.
Result. The advantages of the new approach have been proven: the setpoint acquisition time has been reduced to 20 seconds (15-20% better than traditional methods), overshoot has been eliminated (0% versus 25-30% with the Cohen-Kuhn method), and an optimal transient damping ratio of ψ≥0.85 has been achieved. A significant achievement is the method's versatility, ensuring stable operation with both analog and digital control systems with an error of no more than 3%.
Conclusion. The practical significance of the results is confirmed by the possibility of reducing commissioning time by 25-30% while simultaneously improving control accuracy. The results open up prospects for the development of intelligent control systems that adapt to changing equipment parameters in real time. The method is recommended for implementation at modern NPP units as an effective solution for complex nuclear energy processes.

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