Latvian Maritime academy

The control mechanism of the mathematical model that is used in Simulink is chosen as PIDeffective control mechanism.PID (Proportional, integral, derivative) effective controlA proportional-integral-derivative (PID) controller is widely used in industrial control systems thatinvolve three constant parameters. These parameters are the proportional, integral and derivative values.A PID controller calculates the error value as the difference between the desired input value and theactual output. The controller minimizes the error according to process control inputs.In PID controller, P represents the proportion to the present error at the instant t, I represents theproportion to the integral of the past error up to the instant t while D is representing the proportion to thederivative of the future error at the instant t [13]. In PID effective control system, transfer function,is as given in Eq. 7.ut () 1 de( t)u( t) K pe( t) e()t dt d oidt t(7)Establishment of simulink modelFigure 3. Schematic structure of PID effective control system [14]Due to the fact that ships are consisted of different localities, each locality is modelled individuallyin Matlab-Simulink model. After, these models are integrated together in order to create a total solutionfor the ship air-conditioning system. Because of same method is used in all localities, a Simulink modelfor only one locality (Cabin No. 1) is given in Figure 4 as an example.Simulink models are created for all cabins. The model for three cabins and one corridor is given inFigure 5 for the illustration of the model. Simulations are carried out via these models.17