Multi-area Multi-source System Research Articles

Load Frequency Control of multi-area multi-source system with nonlinear structures using modified Grasshopper Optimization Algorithm

Nowadays, power systems are in direct contact with sources such as renewable energy sources, Electric Vehicles (EVs), distributed generation resources, etc. In other words, these sources impose additional imbalances on the system and disturb the balance between generation and consumption. Hence, this study aims to model multi-area multi-source systems with the presence of units such as thermal, hydro, diesel, and gas units, wind farms, EVs, and energy storage sources. Without a properly coordinated controller, they can expose the system to severe stress under unwanted disturbances and cause it to deviate from normal operating conditions. Therefore, after modeling the proposed system, a Proportional–Integral–Derivative (PID) controller based on a low-pass filter is presented as a widely used device in the industry. Since tuning coefficients of this controller based on trial and error were irrational, this issue turned to a frequency-based optimization problem with different operating points in unwanted operating conditions in order to have a robust design. In the previous articles, a fixed working point employed to design the controller. To cover this issue, modeling towards reality, and a wider range of unexpected conditions and events, ±30% design uncertainty and different loading conditions are considered in this study. Then, the developed Grasshopper Optimization Algorithm (GOA) with decreasing coefficients is applied to solve it. The time-varying coefficients can properly improve the local and global search capabilities. Different scenarios based on unwanted disturbances, uncertainties, and random load changes are considered to evaluate the system and algorithm performance. Numerical results obtained by analyzing comparative criteria on time and frequency domains indicated the proposed method had over 25% better performance compared to other methods, on average. The results obtained from the frequency and time domains properly show that the settlement and overshoot and undershoot times of the system equipped with the proposed controller are less compared to other designs in the literature, and better stability has been provided in the s-plane. Also, Nyquist and Bode analyses have shown that the system can ensure optimal performance in a wide range of working points.

Impact of RFB and PLL Dynamic on Combined ALFC-AVR Regulation of Multiarea Multisource System Under Deregulated Environment with AC/Accurate HVDC link

ABSTRACT The paper discusses the coordinated effect of redox flow battery (RFB) and accurate high voltage dc (AHVDC) link on the combined voltage and frequency control of two-area systems under deregulated environment. Each area has three generating companies (GENCOs) and three distribution companies. GENCOs in Area-1 are thermal, realistic dish-Stirling solar thermal system (RDSTS) and solar thermal power plants, and in Area-2 GENCOs are hydro, RDSTS, and geothermal power plants. Appropriate nonlinearity constraints are equipped with both hydro and thermal units. A maiden attempt has been made to employ a cascaded fractional-order PD with filter and PID with filter (CFOPDN-PIDN) as a secondary controller for the considered system. Artificial flora algorithm is used to optimize the controller parameters under various system conditions. The proposed CFOPDN-PIDN controller yields better system dynamic responses than the PIDN controller for the Poolco, bilateral, and contract violation power transactions. The investigations reveal that the parallel operation of the AC/AHVDC links deteriorates the system dynamics having more oscillations and peak deviations compared to individual AC and AHVDC links. The dynamic effect of Phase-Lock-Loop (PLL) is important for the realistic operation of AHVDC link. A novel approach for analyzing the dynamic effect of the AHVDC links considering PLL effects during the coordination with the AC system is presented. By adding the dynamic model of PLL to the parallel AC/AHVDC link, the system's performance is improved. The analysis reflects that the RFB-AHVDC links with PLL dynamics provided better system damping than the RFB-AC tie-line and AC tie-line alone.

SMES and TCSC Coordinated Strategy for Multi-area Multi-source System with Water Cycle Algorithm Based 3DOF-PID Controller

ABSTRACT This paper attempted to assess the supremacy of designed higher-order degree of freedom (DOF) proportional(P)-integral(I)-derivative(D) (PID) (3DOF-PID) controller making use of a new meta-heuristic optimization approach of water cycle algorithm (WCA) in the study of load frequency control. For this, two test system models of dual area hydro-thermal system system and multiarea multisource systems are believed for investigative purposes. The investigation is performed by imparting the area-1 of test system models with a disturbance of 10% step load (10%SLP). Parameters of 3DOF-PID are rendered optimally over the index of integral square error. Efficacy of the presented 3DOF-PID regulator fine-tuned with WCA is demonstrated with other control schemes that have been implemented on the same test systems. Moreover, superconducting magnetic energy storage and Thyristor controlled series compensator territorial schema is implemented for the MSMA system for performance enhancement. Finally, the robustness of the presented approach is demonstrated through sensitivity analysis.

Analysis of tilt integral derivative controller-based automatic load frequency control of multi-area multi-source system

Analysis of tilt integral derivative controller-based automatic load frequency control of multi-area multi-source system

Analysis of tilt integral derivative controller-based automatic load frequency control of multi-area multi-source system

Analysis of tilt integral derivative controller-based automatic load frequency control of multi-area multi-source system

Combined Voltage and Frequency Control of Multiarea Multisource System Using CPDN-PIDN Controller

This paper discusses a multiarea multi-source system in combined automatic load frequency control (ALFC) and an automatic voltage regulator (AVR) model. The multiarea system comprises thermal and wind in Area-1, thermal-geothermal in Area-2, and hydrothermal plant in Area-3. Appropriate nonlinearity constraints are provided for both hydro and thermal plants. A maiden attempt has been made to employ a cascade proportional-derivative (PD) with filter coefficient (N) and PID with filter coefficient (N) (CPDN-PIDN) as a secondary controller in the combined ALFC-AVR system and optimized controller gains using artificial flora algorithm (AFA). It is examined that the CPDN-PIDN controller yields better dynamics responses than the PI and PIDN controllers. Analyze reflects that the system performance enhanced in the presence of AVR loop. This paper discusses the effect of renewable sources like wind and geothermal on the system dynamics. Analysis reveals that the geothermal power plant is more reliable than the wind plant. The parameter variations of the temporary and permanent droop and hydro turbine time constant (HTTC) of the hydro plant are examined through system responses. System response deteriorates significantly as permanent droop and HTTC are reduced. Peak overshoot and undershoot are reduced considerably as the temporary droop value is increased. Sensitivity analysis reveals that the AFA optimized CPDN-PIDN controller parameters obtained under the nominal condition are resilient enough and need not be reset with the system's substantial random variation. An experimental justification has been provided of the investigated system using a real-time simulation with the OPAL-RT OP4510 real-time setup.

Combined frequency and voltage stabilisation of multi-area multisource system by DE-AEFA optimised PID controller with coordinated performance of IPFC and RFBs

This paper introduces a new-fangled coordinated control mechanism for simultaneous stabilisation of frequency and voltage in multi-area system. A new differential evolution- artificial electric field (DE-AEFA) algorithm is suggested for fine tuning of classical PID as regulator. Viability of DE-AEFA based control scheme is established by counterpointing its dynamic responses with other algorithms and also tested on a widely accepted test system of dual area thermal plant with turbines of non-reheat structure. Further, the dynamic responses of the considered system has been examined by placing interline power flow controller (IPFC) in tie-line and redox flow batteries (RFBs) in both the areas. This investigation depicts the superiority of IPFC and RFBs in mitigating frequency, tie-line and voltage deviations by coordinating with the proposed controller. It is deduced that the proposed coordinated control strategy is highly efficient and surpasses prevalent approaches. Eventually, sensitivity analysis is performed to test control strategy robustness.

Maiden Application of Meta-Heuristic Techniques with Optimized Integral minus Tilt-Derivative Controller for AGC of Multi-area Multi-Source System

This article presents a new meta-heuristic algorithm optimized secondary controller called Integral minus Tilt-Derivative (I-TD) for automatic generation control of three area multi-source system. Area-1 comprises of thermal and solar thermal units, area-2 comprises of two thermal units and area-3 comprises of thermal and wind systems. Comparison of system responses using proposed I-TD controller and some other commonly used controller revels better dynamics characteristics of the proposed one. Dynamic responses of the system corresponding to various meta heuristic optimization technique like firefly algorithm (FA), grey-wolf optimization (GWO), grass-hopper algorithm (GHA) explore that GHA provides slightly better dynamics than the other and also converges faster. Further, sensitivity analysis suggests that system dynamics with GHA optimized I-TD controller at various loading conditions are robust and are not reset again.

Impact Assessment of Vehicle-to-grid Technology in LFC of Multi-area Solar-thermal Power System

This paper presents a load frequency control scheme with the integration of Vehicle-to-grid (V2G) which can enhance the system dynamics under load fluctuations. For this, a detailed multi-area multi-source system is designed with a solar-thermal and a thermal unit in Area1, a gas and thermal unit along with an electric vehicle (EV) fleet in Area2, and two thermal units and an EV fleet in Area3. The thermal units are single reheat turbine type, and appropriate generation rate constraints are considered for thermal and gas units. The application of Two Degree of Freedom Proportional-Integral-Derivative (2DOF-PID) controller has been made as secondary controller in all the control areas. A new nature inspired optimization technique called as Wind Driven Optimization is employed for simultaneous optimization of the controller gains and parameters. Comparison of 2DOF-PID controller with classical controllers reveals the superiority of the former under nominal system conditions. The impact of V2G into the system is tested which proves that the magnitude and numbers of oscillations of the system response is reduced when it encounters load fluctuations. The robustness of the optimized gains and parameters of 2DOF-PID controller have been verified by carrying out sensitivity analysis under different system conditions.

Firefly algorithm optimised PID controller for automatic generation control with redox flow battery

In this article, firefly algorithm-based proportional-integral-derivative controller is employed for the best solution of automatic generation control problem. Initially, a multi-area multi-source system having thermal, hydro and nuclear generating units in each area are considered for analysis purpose with all the probable physical constraints such as boiler dynamics, governor dead band and generation rate constraint. To show the supremacy of proposed FA optimised PID controller, the results are compared with integral and proportional-integral controller for the same power system employing integral time multiplied absolute error as an objective function. Further, to improve the dynamic responses of the system, an energy storage device, redox flow battery is installed in each area. From the simulation results, it is examined that the FA optimised PID controller with RFBs provided the best results compared to others. Finally, to study the robustness of the proposed controller is investigated over a wide variation of system parameters (−25% to +25%) and loading condition. For superior investigation, the proposed method is also investigated by applying random step load and sinusoidal disturbances.

Firefly algorithm optimised PID controller for automatic generation control with redox flow battery

In this article, firefly algorithm-based proportional-integral-derivative controller is employed for the best solution of automatic generation control problem. Initially, a multi-area multi-source system having thermal, hydro and nuclear generating units in each area are considered for analysis purpose with all the probable physical constraints such as boiler dynamics, governor dead band and generation rate constraint. To show the supremacy of proposed FA optimised PID controller, the results are compared with integral and proportional-integral controller for the same power system employing integral time multiplied absolute error as an objective function. Further, to improve the dynamic responses of the system, an energy storage device, redox flow battery is installed in each area. From the simulation results, it is examined that the FA optimised PID controller with RFBs provided the best results compared to others. Finally, to study the robustness of the proposed controller is investigated over a wide variation of system parameters (−25% to +25%) and loading condition. For superior investigation, the proposed method is also investigated by applying random step load and sinusoidal disturbances.