Boundary conditions for the selection of the desired conjugatecomplex or real poles have been set, and they comprise the condition for the controller to operate as a

proportional controller. The illustrative examples of the response of the PI control of UFOPDT for different values of the desired poles and the confirmation of the boundary conditions were received via simulation.

In [17, 18], vector resonant(VR) control method is proposed, where

proportional controller is to adjust the control bandwidth to improve the dynamic response speed, while the resonant controller is to select frequency for specific frequency signal to improve the control accuracy of current.

where [k.sub.D,i] and [k.sub.P,i] are the gains of the derivative and

proportional controller for the [i.sup.th] vehicle.

If input of the fuzzy logic unit is chosen as error (e), then scaling factor and output of the unit are taken as proportional scaling factor (PSF) and gain of the

proportional controller ([K.sub.FP]).

As a result, the

proportional controller is often used in the inner loop, which is regarded as a quick follow-up system.

Results from the optimization of the

proportional controllerThe simplest controller is the

proportional controller, so it was implemented in MATLAB/SIMULINK by replacing the Fuzzy Logic Controller with Ruleviewer block in figure 5 with an amplifier with gain K = 10.

Figure 5 shows the comparison of the frequency response of the position control system between the closed-loop nominal model and the closed-loop actual system with a

proportional controller, whose gain is 1,000.

Due to

proportional controller, response shown in Fig.

The aim of the presented paper is to investigate stability properties of a characteristic closed-loop quasipolynomial when control a selected anisochronic system by a simple

proportional controller. Stability analysis is based on the important finding that the argument principle (i.e.