AUTHOR=Hu Qiankun 

TITLE=Chaotic Oscillation Control Model of Power System Under Electromechanical Power Disturbance

JOURNAL=Frontiers in Energy Research

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2022.887561

DOI=10.3389/fenrg.2022.887561

ISSN=2296-598X

ABSTRACT=<p>The influence of electromechanical power on the power system is controlled in order to stabilize the power system. The author establishes a fourth-order power system model with a power disturbance term based on the dissipative property; the possibility of the existence of a system chaotic attractor is analyzed using the Lyapunov exponent spectrum, bifurcation diagram, phase diagram, spectral entropy, etc., and the influence of the power disturbance term on the motion state of the system is studied. It can be seen that under the influence of the disturbance frequency, the system will exhibit sufficient dynamic behavior. The parameters of the power disturbance term are more sensitive to the influence of the system power angle, and when the disturbance amplitude reaches a certain value, the power angle will increase sharply, and eventually the system will become unstable. The experimental results show that when controller parameters <inline-formula id="inf1"><mml:math id="m1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>c</mml:mi><mml:mn>1</mml:mn></mml:msub><mml:mo>=</mml:mo><mml:msub><mml:mi>c</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mo>=</mml:mo><mml:mn>60</mml:mn></mml:mrow></mml:math></inline-formula> are selected, then<inline-formula id="inf2"><mml:math id="m2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>τ</mml:mi></mml:math></inline-formula> = 0.01, <inline-formula id="inf3"><mml:math id="m3" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>η</mml:mi></mml:math></inline-formula> = 0.3, and <inline-formula id="inf4"><mml:math id="m4" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>ε</mml:mi></mml:math></inline-formula> = 0.001. Moreover, when two groups of different control objectives <italic>r</italic> = 1.2 + 0.1 sin(<italic>t</italic>) and <italic>r</italic> = 1.2 are chosen, it can be clearly seen that the power angle <inline-formula id="inf5"><mml:math id="m5" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>δ</mml:mi></mml:math></inline-formula> in the system is very unstable before the controller is connected and the fluctuations are large and irregular, whereas after the controller is added for 150 s, the power angle <inline-formula id="inf6"><mml:math id="m6" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>δ</mml:mi></mml:math></inline-formula> tends to become stable, the fluctuation range becomes small and regular, and the system has almost no chattering. In order to reflect the superiority of the author’s control method, under the same parameter conditions, the symbolic function <inline-formula id="inf7"><mml:math id="m7" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>θ</mml:mi><mml:mrow><mml:mo>(</mml:mo><mml:mi>s</mml:mi><mml:mo>)</mml:mo></mml:mrow><mml:mo>=</mml:mo><mml:mi>sgn</mml:mi><mml:mrow><mml:mo>(</mml:mo><mml:mi>s</mml:mi><mml:mo>)</mml:mo></mml:mrow></mml:mrow></mml:math></inline-formula> is used as a switching function of the controller and the tracking control numerical simulation is carried out for the same control objectives <italic>r</italic> = 1.2 + 0.1 sin(<italic>t</italic>) and <italic>r</italic> = 1.2. The controller that adopts the relay characteristic function <inline-formula id="inf8"><mml:math id="m8" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>θ</mml:mi><mml:mrow><mml:mo>(</mml:mo><mml:mi>s</mml:mi><mml:mo>)</mml:mo></mml:mrow><mml:mo>=</mml:mo><mml:mfrac><mml:mi>s</mml:mi><mml:mrow><mml:mi>s</mml:mi><mml:mo>+</mml:mo><mml:mrow><mml:mo>|</mml:mo><mml:mi>ε</mml:mi><mml:mo>|</mml:mo></mml:mrow></mml:mrow></mml:mfrac></mml:mrow></mml:math></inline-formula> as a switching function has a better control effect and the system is smooth and stable without chattering.</p>