Abstract: Based on Newton dynamics mechanics theory make a study of two-wheeled self-balancing robot, a detailed mathematical model of the modeling process is provided, and then, using the reasonable method, a linear state-space equations is built up. After that, the LQR controller and state-feedback controller based on pole placement theory are both designed. After a number of simulation experiments, we get the best closed-loop poles and Q, R matrix, both of which have good simulation curves at the same disturbance force. The results of experiments prove that both of them have good dynamic performance and robustness, which also prove the system modeling and controller design are reasonable and effective via these methods. The curves from LQR controller have a better dynamic performance compare with pole placement state-feedback controller.

Abstract: In this article, an existing exact algorithm for identifying a continuous transfer function from frequency data, giving major importance to phase data, is further developed. The new version allows identifying a digital transfer function, or a continuous fractional order transfer function with a fixed order of commensurability (i.e. a ratio of two polynomials in s α, α ∉ ℤ). This is straightforward if the desired transfer function is to have only zeros or only poles; if a transfer function with both zeros and poles is sought, however, a numerical method must be resorted to.

Abstract: Single-phase photovoltaic grid-connected generator systems adopt LCL filter which is useful to restrain high-frequency switching current into the grid.However,the LCL filter increases the system order so that the design of the system stability is difficult to be realized.At present,dual-loop control strategies which consist of dc-side voltage outer loop and grid-side current inner loop have been widely used for single-phase photovoltaic grid-connected generator systems with L or LC filters.But if the dual-loop control is directly used in the photovoltaic system with the LCL filter,the system may be unstable.This paper presented a novel grid-connected control strategy composed of voltage loop,power loop,and capacitor current loop.The voltage loop stabilized the capacitor voltage at dc-side of the grid-connected inverter;the power loop regulated the power factor of photovoltaic grid-connected generating power;both the power loop and the capacitor current loop improved the system stability and suppress resonant peak caused by the LCL filter.The system closed-loop transfer function was derived and the influence of control parameters on the system stability was analyzed with the closed-loop pole distribution.Simulation and experiment results demonstrate the feasibility of the proposed control system.

Abstract: The Inverted Pendulum System is an under actuated, unstable and nonlinear system. Therefore, control system design of such a system is a challenging task. To design a control system, this thesis first obtains the nonlinear modeling of this system. Then, a linearized model is obtained from the nonlinear model about vertical (unstable) equilibrium point. Next, for this linearized system, an LQR controller is designed. Finally, a PID controller is designed via pole placement method where the closed loop poles to be placed at desired locations are obtained through the above LQR technique. The PID controller has been implemented on the experimental set up.

Abstract: In this paper, a robust state feedback control design using particle swarm optimisation-based constrained optimisation is proposed. The feedback controller is designed based on state space model of the plant with structured uncertainty such that the closed-loop system would have maximum stability radius. A wedge region is assigned as a constraint to locate desired closed loop poles. The proposed method is applied into design of anti-swing control of an automatic gantry crane experiment. A comparison with that of LQR-based controller is made. The result shows that the proposed method effectively locates the closed loop poles within the prescribed wedge region and its robust performance is guaranteed.

Abstract: This study presents the derivations of the voltage transfer functions of the amplifier A, the feedback network β, the loop gain T, the closed-loop gain Af and also the characteristic equation for the common-gate (CG) Colpitts oscillator, using the small-signal model of the metal-oxide-semiconductor field-effect transistor (MOSFET) CG Colpitts oscillator. Using the characteristic equation, the expressions for the oscillation frequency of the sinusoidal output voltage and the condition for oscillation in steady state are derived. The characteristic equation is also used to obtain a plot of trajectories of the closed-loop poles of the CG Colpitts oscillator by varying the MOSFET small-signal transconductance gm. The locations of the complex conjugate poles of closed-loop gain that depict the starting and steady-state conditions for oscillations are presented. Nyquist plots of the loop gain are given to illustrate the startup and steady-state conditions of oscillations. Simulation and experimental results to verify the theory are also given.

Abstract: In this paper we propose an optimal controller synthesis method when a prescribed set of closed-loop poles is given. This technique relies on the specification of a closed-loop polynomial with degree greater than the minimal degree that ensures the existence of the pole-assignment equation solution. The degree difference generates an infinite number of solutions that correspond to non-minimal controllers. The set of free controller parameters are then chosen to optimize a ℋ 2 cost function.

Abstract: To a class of discrete interval systems, this paper introduces a class of method of designing the state and output feedback gain which place the closed-loop poles of a given discrete interval system inside a specified circular disc, in terms of LMIs. The reliable controllers of actuator failure model and sensor failure model are also presented in this paper. At the end of this paper, numerical examples are also given to illustrate the design procedures and their effectiveness.

Abstract: SUMMARY This work is concerned with analysis of uncertain control systems, with regard to clustering of poles inside a simple symmetric bounded contour. We present and we use the generalized Bode envelopes, generalized Mikhailov theorem, and the generalized Nyquist theorem for the simultaneous analysis of stability and quality of transient response of uncertain systems. Our results allow one to determine the number of open and closed loop poles inside the given symmetric simply connected contour, for the entire uncertain family. The proposed method is computationally efficient and appropriate for solving complex control analysis problems, as evidenced in the examples. Copyright c

Abstract: The problem of block decoupling is studied for the case of general neutral multi delay systems. The system is not restricted to be square and invertible. The controller is of the general neutral dynamic type involving a dynamic feedback and dynamic precompensator. Two different cases of feedback are studied. The first is the case of measurable output feedback and second is the case of performance output feedback. The controller is restricted to be realizable. The necessary and sufficient conditions for the problem to be solvable are established. The general class of the realizable controllers solving the problem is derived. The closed loop transfer function is proven to have arbitrary characteristic polynomial thus facilitating command tracking and stability.

Abstract: Nonlinear phenomena largely characterize the real, surrounding world. One of the major targets of last decade automatic control is finding better solutions for nonlinear control. From this point of view, the paper proposes a hybrid (compensator based, feedback-feedforward) structure as control solution for some classes of nonlinear processes. This is developed using the nonlinear geometric characteristic of the process and a classical robust control algorithm. The components of the proposed structure are designed based on experimental tests, classic identification and closed loop pole placement methods. The applicability of the different implementations of the structure, suitable for each class of studied nonlinear processes, is demonstrated with a real-time control application implementing RST numerical algorithms. The software and the obtained results are presented and commented in terms of efficiency, advantages and disadvantages.

Abstract: An algorithm for control of nonlinear discrete-time systems is presented in the paper. Controlled system is linearized by dynamic output feedback so that the linearized closed loop system is equivalent to a predefined discrete-time transfer function representing reference model of the control system. Choice of the reference model provides placement of zeroes and poles of the closed loop system. In the proposed approach at least one of the poles is not fixed and moves during the time of transient process. Evolution of the pole occurs according to certain rules formalized and implemented in the algorithm by means of fuzzy logic. Therefore, the parameters of the transfer function of the linearized closed loop system may be understood as nonlinear functions which depend on the current control error and its derivative. Thus the poles of the closed loop system are placed dynamically according to the predefined rules providing necessary behavior of the control system. Controlled system has to be represented by a nonlinear model with no couplings between different time instances what can be performed by training an Artificial Neural Network of the specific structure. The developed theory and control algorithm are illustrated by means of numerical example.

Abstract: A new way, which is used to analysis the path contribution, is presented for the vibration transfer path systems considering the interact of vibration source, transfer path and receiver. It is that the path contribution is evaluated using the path transfer probability. According to the dynamic characteristics of vibration systems, the new concept of path transfer probability is given. Based on the generalized probabilistic perturbation method and the reliability theory, the computational approach for path transfer probability with uncertain physics and geometry factors in time range are presented. The transfer probability of vibration transfer path systems with translational and rotational motions is analyzed and calculated via a numerical example, which shows that the proposed method is feasible.

Abstract: This paper presents a robust control design based on constrained optimization using Differential Evolution (DE). The feedback controller is designed based on state space model of the plant considering structured uncertainty such that the closed-loop system would have maximum stability radius. A wedge region is assigned as a constraint for desired closed loop poles location. The proposed control technique is applied to a two-mass system that is known as benchmark problem for robust control design. The simulation results seem to be interesting in which the robustness performance is achieved in the presence of parameter variations of the plant.

Abstract: Traditional Direct Current Speed Control System is designed mainly by adopting engineering method and is widely used in practice. In this paper, a new approach is proposed for the design of this kind of control system based on the combination of classic design method and modern control theory, and it can avoid the problems occurred in engineering method, in which the closed-loop poles cannot be randomly configured. Firstly, the system is designed on modern control theory and then implemented through classic method of equivalent transformation of structure. Secondly, simulation is done in matlab/simulink from the data obtained. Finally, disturbance resistance emulation is carried out respectively through traditional method and the method in this paper, which demonstrates the effectiveness of this method.