Pole Assignment Technique Research Articles

Design of Stabilizing Controllers of Power System Using Pole-Assignment Technique

A method of designing stabilizing controllers is presented in this paper. The controller parameters are determined by pole-assignment technique based on the first and second order eigenvalue sensitivities. The method is applied to a single-machine infinite-bus system and a two-machine infinite-bus system, and the performances of these systems are studied. The results are proved to be very useful for designing decentralized controllers of large-scale power systems and low sensitive controllers to variations of the operating point.

Coherency Based Design of Decentralized Optimal Controllers for Stabilization of Large Power Systems

This paper gives a new procedure for the design of decentralized optimal controllers for very large power systems. The group of machines, comprising one decentralized area is identified by a coherency recognition algorithm. The coupling between the elements within the group is strong and the coupling between groups are weak. This principle is used to identify the groups. A pole assignment technique, which requires calculation of one eigenvector only, for shifting one eigenvalue is used. This method requires only less computer storage and less computing time, yet achieving results very much comparable with the design of full controllers. The procedure is illustrated with an example. This has very good applications in the design of optimal controllers for large power systems and in their dynamic analysis.

Pole Assignment Into a Sector Using Output Feedback with Gain Minimization

Pole assignment techniques are effective in designing feedback controllers to obtain improved response of linear, time invariant dynamical systems. State feedback may pose problems in practical implementation. In such cases output feedback controllers have to be considered.From the viewpoint of satisfactory closed loop system performance assignment of closed loop poles at certain specified locations is not necessary. They may be required to be inside a specified sector in the left half plane. This not only ensures satisfactory system behaviour but also provides freedom in the choice of the feedback controller, both in the single and multi input cases. This freedom can be used to satisfy additional design criteria such as that the feedback gains or sensitivity of closed loop eigenvalues to specified system parameters should be minimum.A simple procedure is presented to design a minimum gain output feedback controller which assigns the closed loop poles into a specified sector. Numerical examples are given to illustrate the procedure.

New algorithm for the optimal stabilisation of linear systems using pole-assignment techniques

In this paper, a new algorithm for the design of optimal controllers of large-scale linear systems using a pole-assignment technique to achieve a desired degree of stability is presented. The method is based on obtaining the weighting matrix Q of a suitable quadratic performance index and the optimal-control matrix F that correspond to the desired closed-loop eigenvalues of the system. To achieve this, a reduced model, retaining only those eigenvalues of the original system which are to be shifted, is considered, and it has been proved that, if a suitable weighting matrix Q and an optimal control matrix F of the reduced model having the desired set of eigenvalues are found, a simple matrix manipulation yields the weighting matrix Q and the control matrix F of the original large-scale system. The algorithm has been illustrated with an example.

Pole assignment with minimum eigenvalue sensitivity to plant parameter variations

A procedure for designing a constant gain feedback matrix which assigns the closed-loop poles of a linear time-invariant multivariable system to desired locations and at the same time minimizes the sensitivity of these poles to variations in the parameters of the plant is described in this paper. It is shown that this technique in which sensitivity considerations are an integral part of the design procedure yields better results compared to other pole assignment techniques using constant gain feedback controllers. Numerical examples are presented to illustrate the application of the design procedure.

Design of dynamical compensators for pole assignment

The problem of designing dynamic output feedback compensators to achieve arbitrary polo assignment in linear multivariable systems is considered. By extending a reeent pole assignment technique using constant output feedback to include dynamic output feedback, a procedure is developed for the design of unit rank dynamic compensators for arbitrary pole placement. The design is carried out entirely in the frequency domain and the key step in the design is the formation of a set of linear equations relating the parameters of the compensator to the desired closed-loop characteristic polynomial. The problem of assigning the poles of the compensator which achieves arbitrary pole placemont is also considered.

Stabilization of a power system through output feedback

The optimal stabilization of a power system using the state variable feedback has the drawback that all the state variables are not available for measurement. A suboptimal control policy for stabilization of a power system is proposed, using the available output variables and employing the pole assignment technique. The proposed scheme is illustrated with an example.

New algorithm for the optimal stabilisation of linear systems using pole-assignment techniques

In this paper, a new algorithm for the design of optimal controllers of large-scale linear systems using a pole-assignment technique to achieve a desired degree of stability is presented. The method is based on obtaining the weighting matrix Q of a suitable quadratic performance index and the optimal-control matrix F that correspond to the desired closed-loop eigenvalues of the system. To achieve this, a reduced model, retaining only those eigenvalues of the original system which are to be shifted, is considered, and it has been proved that, if a suitable weighting matrix Q̂ and an optimal control matrix F̂ of the reduced model having the desired set of eigenvalues are found, a simple matrix manipulation yields the weighting matrix Q and the control matrix F of the original large-scale system. The algorithm has been illustrated with an example.

Design of multivariable systems using unity-rank feedback†

Existing pole-assignment methods are inadequate as a complete design technique for linear multivariable systems since other design factors such as zero positions, steady-state characteristics, integrity, etc., must also be taken into account. This paper extends an existing pole-assignment technique, employing unity-rank feedback, to account for such additional design features. For an nth-order multivariable system with m inputs and l outputs, it is shown that there are essentially m − 1 independent variables available in the design process. When complete state feedback or output feedback with l = n is used, these m − 1 degrees of freedom are available to meet specifications in addition to pole assignment. When incomplete state feedback or output feedback with l less than n is used, these m − l degrees of freedom must be shared between pole-assignment and the other design features. The method is computationally fast and is well suited to the computer-aided design of control systems. A number of illustrative examples are given.