Self-tuning control schemes need many control parameters corresponding to the order and the time-delay of the controlled object. Using such many control parameters yields the inferiority in the transient property. Therefore, in order to design practical self-tuning controllers, it is seemed that it is desirable to construct control systems with as few parameters as possible. In this paper, we propose a method how to tune PID parameters adaptively, that is, a self-tuning PID control scheme, based on the relationship between a generalized minimum variance control (GMVC) law and a PID control law. Furthermore, we consider a design scheme of user-specified parameters included in the cost function of the GMVC. Finally, we apply the proposed scheme to an air pressure control system in order to investigate the effectiveness.
In Japan, about 84 percent of real plants adopt PID controllers. However, when we use them, we are required much effort and time for tuning the PID gains. In this paper, we propose a method using a neural network stabilization of the inverted pendulum which is the single input and two outputs system. Here, we propose a neuro-PD control system to stabilize the inverted pendulum, which consists of two PD controllers and a neural network to tune the PD gains. Finally, the experimental results to stabilize the inverted pendulum are illustrated to show effectiveness of the present method.
Generally, industrial processes are too complex to obtain precise dynamics of a plant. Therefore, a controller is required to have robustness property in that it can attain acceptable control performance and closed-loop stability in the presence of plant uncertainty. In this paper, we proposed the unified design method for robust PID controller with two degrees of freedom which satisfies multiple design specifications based on the matrix inequality approach. And we propose a new genetic algorithm for solving this matrix inequality problem, because this problem is not formulated as the linear matrix inequality problem. And this method demonstrated by numerical simulations and shows good performance.
In this paper, a method to compute an almost correct region of PID parameters which guarantees robust stability and several robust performances for systems with real uncertain parameters is proposed. The proposed method can be compute the region in a short computing time by adopting the following idea and technique : The first one is the computational strategy to avoid the unnecessary small splitting of the parameter space of the PID controller. The second one is adopting the idea of computational geometry approach to reduce the time for executing the algorithm. The third one is to use the Non-convex Polygon Interval Arithmetic (NPIA) to compute the “good” estimate of value sets of transfer functions.
In this paper, a design method of a single-input single-output PID controller for H∞ control problem is proposed. Since the H∞ norm constraint consists of an internal stability condition and a frequency domain condition on the jω axis, the solution set of the PID gains for the H∞ control problem is given on a parameter plane as the intersection of the two sets which satisfy the above two conditions. As for the computation of the latter set, two methods are proposed. One is a method in which the set is directly computed from the frequency domain condition, and the other is a method in which the set is computed by using the parametrization of all the H∞ control solutions.
In this paper, we study the accuracy of the open-loop frequency response of control system obtained by on-line identification from the closed-loop frequency response, and show that the open-loop frequency response required for design based on the frequency response can be obtained accurately. Moreover, we consider feedforward-type two-degree-of-freedom PID control systems, and propose an on-line design method of feedback controllers, and a design method of feedforward controllers focused on the number of phase-lead elements between the reference input and the manipulated input. Furthermore, combining these design methods, an on-line design method of two-degree-of-freedom PID control systems is proposed. The efficiency of the proposed design method is evaluated by simulation.