Abstract
This article studies the impact of incommensurate communication time delays on stability regions defined in proportional-integral (PI) controller parameter space for a two-area load frequency control (LFC) system. Distributed power generations and large power plants increase the complexity and control issues of interconnected power systems. In interconnected power systems, LFC systems need to have complex communication networks to exchange data between control center and geographically dispersed generations. The receiving/transmitting of remote measuring data through communication infrastructures causes inevitable time delays, which adversely affect controller performance and stability of the LFC system. Time delays introducing feedback control loops of a multiarea LFC system could exhibit incommensurate characteristics. In this study, a simple graphical method based on extracting a stability boundary locus is implemented to get PI controller parameters responsible for stabilizing the LFC system having incommensurate delay values. The boundaries of the stability regions in the PI controller parameter space are confirmed by time-domain simulations and a numerical algorithm known as the quasipolynomial mapping-based root finder algorithm. Results illustrate that incommensurate delays have remarkable effects on the stability region.
Highlights
This study aims to compute all proportional-integral (PI) controller gains constituting a region in the parameter space of the controller for a conventional two-area load frequency control (LFC) system with constant incommensurate communication delays
This paper has presented the implementation of a stability boundary locus method to determine all stabilizing PI controller parameters that constitute a stability region in the PI controller parameter space for two-area LFC systems with multiple incommensurate time delays
It is clearly seen from the results that the largest PI controller set is obtained for the delay case in which the delay for area 1 is greater than the delay for area 2
Summary
This study aims to compute all proportional-integral (PI) controller gains constituting a region in the parameter space of the controller for a conventional two-area load frequency control (LFC) system with constant incommensurate communication delays. Wide-area measurement/monitoring systems (WAMSs) comprise extensively open and distributed communication networks that cause unavoidable time delays in electrical power systems [2], in LFC systems. The task of communication networks is to transmit real-time measurement data using synchronous phasor measurement units and global positioning systems from power plants to control centers or vice versa. Time delays observed because of the complex communication networks and digital measuring devices cause a poor dynamic performance of the controller and have an adverse effect on the dynamics and stability of the LFC system [3–-6]. Remote measuring data obtained from WAMSs must be transmitted to a control center at long distances through open and distributed communication networks.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
