Thyristor control series capacitor ANFIS controller for damping oscillations

This study applies Adaptive Neuro Fuzzy Inference System (ANFIS)-based TCSC controller for damping oscillations. ANFIS which tunes the fuzzy inference system with a back propagation algorithm based on collection of input-output data makes fuzzy system to learn ANFIS controller is designed to damp out the low frequency local and inter-area oscillations of the Multimachine power system. Direct inverse control techniques are used in the design-of TCSC ANFIS controller which is derived directly from neural networks counterpart’s methodologies of the power system and the controller network to provide optimal damping. By applying this controller to the TCSC devices the damping of inter-area modes of oscillations in a multi-machine power system is handled properly. The effectiveness of the proposed TCSC ANFIS controller is demonstrated on two area four machine power system (Kundur system) which has provided a comprehensive evaluation of the learning control performance. Finally, several fault and load disturbance simulation results are presented to stress the effectiveness of the proposed TCSC controller in a multimachine power system and show that the proposed intelligent controls improve the dynamic performance of the TCSC devices and the associated power networ

MODELING AND CONTROL OF INTERLINE POWER FLOW CONTROLLER FOR POWER SYSTEM STABILITY ENHANCEMENT

Mitigation of power system oscillations is the problem of concern in the power industry as these oscillations, when exhibiting poor damping; affect the transmission line power transfer capability and power system stability. These oscillations greatly restrict power system operations and, in some cases, can also lead to widespread system disturbances. In this context, the Flexible AC Transmission System (FACTS) device, Interline Power Flow Controller (IPFC) employed to improve the transmission capability can be additionally utilized for damping control of power system oscillations. IPFC based damping controller design for power system stability requires proper and adequate mathematical representation of power system incorporating the FACTS device. This thesis reports the investigation on the development of steady state model, the dynamic nonlinear mathematical model of the power system installed with the IPFC for stability studies and the linearized extended Phillips Heffron model for the design of control techniques to enhance the damping of the lightly damped oscillations modes. In this context, the mathematical models of the single machine infinite bus (SMIB) power system and multi-machine power system incorporated with IPFC are established. The controllers for the IPFC are designed for enhancing the power system stability. The eigenvalue analysis and nonlinear simulation studies of the investigations conducted on the SMIB and Multi-machine power systems installed with IPFC demonstrate that the control designs are effective in damping the power system oscillations. The results presented in this thesis would provide useful information to electric power utilities engaged in scheduling and operating with the FACTS device, IPFC

MISO Damping Controller Design for a TCSC Using Particle Swarm

This paper presents a new approach for designing multi-input-single-output (MISO) damping controller for a TCSC in a multi-machine power system. The damping controller design uses particle swarm optimization (PSO) to determine the coefficients of single or multi-stage lead-lag compensators. The classical technique works well in the design of lead-lag compensators for SISO controllers. But, there is no proper step-by-step procedure to achieve the desired performance characteristics for a MISO controller. Hence, in this paper, a computational optimization tool has been used to determine the optimal gains and time constants of a linear MISO damping controller. The damping controller is implemented for a TCSC on a multi-machine multi-modal power system and has shown considerable improvement in minimizing system oscillations

Mitigation of Power System Oscillation in a DFIG-Wind Integrated Grid: A Review

The continuous rise in demand for power supply has made researchers and power system engineers seek alternatives through renewable energy sources to complement the power supply in the power system grid. Wind energy conversion system (WECS) which is the means of harnessing power generation through wind is reportedly one of the most widely installed renewable alternative sources globally. Integrating WECS into the conventional power system grid results in a complex power system grid. Thus, during a disturbance or a fault period on the grid, if proper control measures are not put in place, power system instability due to power system oscillations arises. One such control measure is the damping controller which is coupled to the generating plant through its excitation system. Damping controllers help to dampen power system oscillations, but due to the dynamic nature of the power system and uncertainties inherent in a wind-integrated power grid system, fixed damping controller parameters cannot effectively dampen power system oscillations. Hence, damping controller design becomes an optimization problem. This research reviews damping controller design in a wind-integrated system using optimization techniques

Design of Hybrid Intelligent Power System Stabilizer for a Multi-Machine System

In this project a coordinated design of Fuzzy Power System Stabilizer (FPSS) and TCSC based power oscillation damping (POD) controller to improve power system small-signal stability need to be designed. Two controllers are used for optimizing the system for a better result. Conventional power system stabilizer is replaced by a Fuzzy PSS and the Particle Swarm Optimization (PSO) algorithm tries to minimize an eigenvalue-based multi-objective function by optimizing the parameters of the POD controller. Time domain simulations in MATLAB/SIMULINK performed on a two area four machine (2A4M) power system reveals that superior enhancement in damping of oscillations is achieved by employing coordinated control of FPSS-POD controller in comparison with conventional PSS-POD controller

Recurrent neuro fuzzi controller power system stabilizer

Power system stabilizers (PSS) have been widely used to damp low frequency electromechanical oscillations which occur in power systems due to disturbances. If no adequate damping is available, the oscillation can increase and cause system separation. Power system stabilizers (PSS) are installed in power system generator to help the damping of power system oscillations. There are many approaches to enhance damping while extending the power stability limit. To improve power system stabilizer (PSS) design problem include optimal control ,adaptive and self-tuning control, PID control, robust control, variable structure control and intelligent control. In this paper the power stabilizer is based on Recurrent Neuro-fuzzy Inference System (RNFIS) design controller. In order to test the robustness of the proposed design procedure of the (RNFIS), simulations will be carried out for the three-phase to ground fault and 1- phase fault at the middle of one of the transmission line. After these simulations, we will compare the result between a lead-lag and recurrent neuro-fuzzy controllers to see their difference in disturbances. The optimal solutions will be compared where the expected result will show that the oscillations in time response of the machine speed and the rotor angle is damped more effectively when the recurrent neuro-fuzzy controller and applied to the system

Robust state feedback controller design of STATCOM using chaotic optimization algorithm

In this paper, a new design technique for the design of robust state feedback controller for static synchronous compensator (STATCOM) using Chaotic Optimization Algorithm (COA) is presented. The design is formulated as an optimization problem which is solved by the COA. Since chaotic planning enjoys reliability, ergodicity and stochastic feature, the proposed technique presents chaos mapping using Lozi map chaotic sequences which increases its convergence rate. To ensure the robustness of the proposed damping controller, the design process takes into account a wide range of operating conditions and system configurations. The simulation results reveal that the proposed controller has an excellent capability in damping power system low frequency oscillations and enhances greatly the dynamic stability of the power systems. Moreover, the system performance analysis under different operating conditions shows that the phase based controller is superior compare to the magnitude based controller

MODELING AND CONTROL OF INTERLINE POWER FLOW CONTROLLER FOR POWER SYSTEM STABILITY ENHANCEMENT

Mitigation of power system oscillations is the problem of concern in the power industry as these oscillations, when exhibiting poor damping; affect the transmission line power transfer capability and power system stability. These oscillations greatly restrict power system operations and, in some cases, can also lead to widespread system disturbances. In this context, the Flexible AC Transmission System (FACTS) device, Interline Power Flow Controller (IPFC) employed to improve the transmission capability can be additionally utilized for damping control of power system oscillations. IPFC based damping controller design for power system stability requires proper and adequate mathematical representation of power system incorporating the FACTS device. This thesis reports the investigation on the development of steady state model, the dynamic nonlinear mathematical model of the power system installed with the IPFC for stability studies and the linearized extended Phillips Heffron model for the design of control techniques to enhance the damping of the lightly damped oscillations modes. In this context, the mathematical models of the single machine infinite bus (SMIB) power system and multi-machine power system incorporated with IPFC are established. The controllers for the IPFC are designed for enhancing the power system stability. The eigenvalue analysis and nonlinear simulation studies of the investigations conducted on the SMIB and Multi-machine power systems installed with IPFC demonstrate that the control designs are effective in damping the power system oscillations. The results presented in this thesis would provide useful information to electric power utilities engaged in scheduling and operating with the FACTS device, IPFC