Sliding Mode Control of Two-Parameter Fourth-Order Chaos Model of Power System
Abstract : As a complex nonlinear system, the power system in operation may experience chaotic oscillation which can threaten the stability of the system for unexpected events and uncertain factors. Initially, through considering factors such as the generators, the power system node voltage amplitude and phase angle, this article establishes a fourth-order power system dynamic model and a two-parameter fourth-order power system mathematical model with load reactive power and mechanical input power as chaotic parameters to explore the mechanism and characteristics of chaos in the power system with the chaos theory. In addition, a sliding mode controller based on exponential reaching law for four state variables is designed, which is used to suppress the chaotic oscillation of the power system and guarantee the system can work stably at the target operating point within the chaotic parameter range. The designed controller can effectively suppress the chaos in power system and has an ideal performance.
? In this paper, a four-dimensional power system model with electromagnetic and load power disturbance is built at the same time.
? While power stimulating the production and consumption of energy and improving the quality of daily life, it has also brought about some negative effects.
? New and expanding technologies for electric power generation and application, such as photovoltaic (PV) and wind power generation, switching power converters, have great impact on power systems.
? The validity of the chaotic motion criterion through numerical simulation was verified, which was helpful to better understand the nonlinear dynamic behavior of singlemachine infinite-bus (SMIB) power system.
? The responses of the states of the system sufer from the well-known chattering problem. Therefore, in the next section, we will use a second-order sliding mode controller to reduce the chattering problem.
? The controllers given by and sufer from chattering. To remedy this problem, we propose to use the second-order super-twisting sliding mode controller.
? Several types of SMC control schemes were designed to control the chaos and to avoid voltage collapse in power systems. However, SMC schemes sufer from the problem of chattering which is undesirable in practice.
• The second order power system with chaotic oscillation dynamic behaviors was studied and proposed fuzzy fast terminal sliding mode controller based on equivalent control to stabilize the power system to synchronization status.
• The chaotic oscillation caused by the power disturbance may lead to unstable operation of the power grid.
• Therefore, a fourth-order power system model with power disturbance is established in this paper.
• The nonlinear characteristic of the system under multiple disturbances is studied through the bifurcation diagram, Lyapunov exponent spectrum and the phase plane.
? The performance of the closed loop system when using the proposed feedback linearization controller was simulated using the MATLAB sofware.
? The performance of the closed loop system when using the conventional sliding mode controller was simulated using the MATLAB sofware.
? The initial and the desired states of the power system are the same as in the previous section.
? The performance of the closed loop system when using the second-order super-twisting sliding mode controller was simulated.
? Electric power systems are generally comprised of threephase AC systems operating essentially at constant voltages.
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