Many real time processes have complex, uncertain and nonlinear dynamics. Boilers are nonlinear, time varying, multi-input multi-output (MIMO) systems, whose states generally vary with operating conditions. The major problem in controlling that system is that its drum water pressure and steam flow dynamics include an integrator that results a critically stable behavior. Conventional controller p...

ABSTRACT: This paper focuses on design of nonlinear power plant controller using immune based multiobjective fuzzy approach. The thermal power plant is typically regulated by the fuel flow rate, the spray flow rate, and the gas recirculation flow rate. However, Strictly maintaining the steam temperature can be difficult due to heating value variation to the fuel source, time delay changes in th...

Low Frequency Oscillations (LFO) occur in power systems because of lack of the damping torque in order to dominance to power system disturbances as an example of change in mechanical input power. In the recent past Power System Stabilizer (PSS) was used to damp LFO. FACTs devices, such as Unified Power Flow Controller (UPFC), can control power flow, reduce sub-synchronous resonance and increase...

This paper describes and validates transient stability and power flow model of a Unified Power Flow Controller (UPFC), and presents a detailed comparison of different controls strategies, proposing novel, efficient and simple controls for this controller. The proposed model accurately represents the behavior of the controller in quasi-steady state operating conditions, and hence is adequate for...

This paper proposes a method for extending the ability of rotary power flow controller (RPFC) using tap-changer of the RPFC’s transformers. A detailed model of the device is presented to analyze the effects of the tap changer operation on the performance of the RPFC. To evaluate the results, the RPFC model is simulated using PSCAD/EMTDC software. Dynamic operation of the RPFC on a 400 kV transm...

Flexible Alternating Current Transmission Systems (FACTS) devices have been used for several targets in power system, one of the main contributions of the devices is improving operation conditions. In this paper, two types of these devices have been placed to raise voltage profile, minimizing system loss and arising loadability. The suggested FACTS devices are: Unified Power Flow Controller (UP...

This report describes and validates a transient stability and power flow model of a Unified Power Flow Controller (UPFC), and presents a detailed comparison of different controls strategies, proposing novel, efficient and simple controls for this controller. The proposed model accurately represents the behavior of the controller in quasi-steady state operating conditions, and hence is adequate ...

This paper presents a novel multi-port DC/DC converter which is suitable to be used as the interface of hybrid renewable energy systems. The converter contains three unidirectional power flow ports which two of them are input ports and are connected to two independent energy sources while the third one is the output port that feeds a standalone load. Furthermore, the proposed converter contains...