Dear Editor,This letter is concerned with stability analysis and stabilization design for sampled-data based load frequency control(LFC) systems via a data-driven method. By describing the dynamic behavior of LFC syst...Dear Editor,This letter is concerned with stability analysis and stabilization design for sampled-data based load frequency control(LFC) systems via a data-driven method. By describing the dynamic behavior of LFC systems based on a data-based representation, a stability criterion is derived to obtain the admissible maximum sampling interval(MSI) for a given controller and a design condition of the PI-type controller is further developed to meet the required MSI. Finally, the effectiveness of the proposed methods is verified by a case study.展开更多
为提高系统鲁棒性并且增强对网络诱导时滞的可容许能力,提出一种新型电力系统负荷频率控制(load frequency control,LFC)的时滞相关鲁棒H_(∞)控制设计方法。首先,基于PI型LFC控制策略,建立了考虑时滞的新能源并网多区域新型电力系统LF...为提高系统鲁棒性并且增强对网络诱导时滞的可容许能力,提出一种新型电力系统负荷频率控制(load frequency control,LFC)的时滞相关鲁棒H_(∞)控制设计方法。首先,基于PI型LFC控制策略,建立了考虑时滞的新能源并网多区域新型电力系统LFC模型。其次,使用增广型Lyapunov-Krasovskii(L-K)泛函和自由矩阵不等式估计技术,建立了电力系统LFC的时滞相关鲁棒H_(∞)稳定和镇定条件。最后,以新能源并网的单区域和三区域LFC系统为例,验证了所提方法的有效性和优越性。展开更多
Future energy descent systems will be expected to be controlled by the using of renewable power sources of which wind energy is one of the favorable sources. This paper treats with the implantation of genetic algorith...Future energy descent systems will be expected to be controlled by the using of renewable power sources of which wind energy is one of the favorable sources. This paper treats with the implantation of genetic algorithms for making the parameters needed for PID applied to interconnected thermal and hydraulic power systems at best use and most effective. Two-areas of hydraulic and thermal power systems with wind connected parallel to each one are considered to exemplify the effective parameter investigation. First hydraulic and thermal are connected with tie line with the wind connected parallel to hydraulic or thermal, and then disturbance was made at thermal power plant, then to hydraulic power plant. Simulations are performed aided by the integrated Simulink/Matlab environment taking into consideration the genetic optimization process. Multiple integral representations variables with different cost functions were considered in the search for the effective AGC parameters. The outcomes established by this paper shows the impact of the genetic algorithms for LFC about multiple areas connected power systems based on different wind power using in the tuning of such a process.展开更多
As English serves as an international language(or Lingua Franca),increasing attention is paid to English pedagogy of English as International Language(EIL).This essay maintains that international mutual intelligibilit...As English serves as an international language(or Lingua Franca),increasing attention is paid to English pedagogy of English as International Language(EIL).This essay maintains that international mutual intelligibility is a more practical and achievable goal in English pronunciation pedagogy,compared with native-like proficiency and various of standard English.Meanwhile,Jenkins(2000)’s Lingua Franca Core(LFC),a Phonological Core for EIL,is briefly introduced.展开更多
With rapidly growing of Renewable Energy Sources(RESs)in renewable power systems,several disturbances influence on the power systems such as;lack of system inertia that results from replacing the synchronous generator...With rapidly growing of Renewable Energy Sources(RESs)in renewable power systems,several disturbances influence on the power systems such as;lack of system inertia that results from replacing the synchronous generators with RESs and frequency/voltage fluctuations that resulting from the intermittent nature of the RESs.Hence,the modern power systems become more susceptible to the system instability than conventional power systems.Therefore,in this study,a new application of Superconducting Magnetic Energy Storage(SMES)(i.e.,auxiliary Load Frequency Control(LFC))has been integrated with the secondary frequency control(i.e.,LFC)for frequency stability enhancement of the Egyptian Power System(EPS)due to high RESs penetration.Where,the coordinated control strategy is based on the PI controller that is optimally designed by the Particle Swarm Optimization(PSO)algorithm to minimize the frequency deviations of the EPS.The EPS includes both conventional generation units(i.e.,non-reheat,reheat and hydraulic power plants)with inherent nonlinearities,and RESs(i.e.,wind and solar energy).System modelling and simulation results are carried out using Matlab/Simulink^(■)software.The simulation results reveal the robustness of the proposed coordinated control strategy to preserve the system stability of the EPS with high penetration of RESs for different contingencies.展开更多
基金supported in part by the National Natural Science Foundation of China(62373337,62373333)the 111 Project(B17040)State Key Laboratory of Advanced Electromagnetic Technology(2024KF002)
文摘Dear Editor,This letter is concerned with stability analysis and stabilization design for sampled-data based load frequency control(LFC) systems via a data-driven method. By describing the dynamic behavior of LFC systems based on a data-based representation, a stability criterion is derived to obtain the admissible maximum sampling interval(MSI) for a given controller and a design condition of the PI-type controller is further developed to meet the required MSI. Finally, the effectiveness of the proposed methods is verified by a case study.
文摘为提高系统鲁棒性并且增强对网络诱导时滞的可容许能力,提出一种新型电力系统负荷频率控制(load frequency control,LFC)的时滞相关鲁棒H_(∞)控制设计方法。首先,基于PI型LFC控制策略,建立了考虑时滞的新能源并网多区域新型电力系统LFC模型。其次,使用增广型Lyapunov-Krasovskii(L-K)泛函和自由矩阵不等式估计技术,建立了电力系统LFC的时滞相关鲁棒H_(∞)稳定和镇定条件。最后,以新能源并网的单区域和三区域LFC系统为例,验证了所提方法的有效性和优越性。
文摘Future energy descent systems will be expected to be controlled by the using of renewable power sources of which wind energy is one of the favorable sources. This paper treats with the implantation of genetic algorithms for making the parameters needed for PID applied to interconnected thermal and hydraulic power systems at best use and most effective. Two-areas of hydraulic and thermal power systems with wind connected parallel to each one are considered to exemplify the effective parameter investigation. First hydraulic and thermal are connected with tie line with the wind connected parallel to hydraulic or thermal, and then disturbance was made at thermal power plant, then to hydraulic power plant. Simulations are performed aided by the integrated Simulink/Matlab environment taking into consideration the genetic optimization process. Multiple integral representations variables with different cost functions were considered in the search for the effective AGC parameters. The outcomes established by this paper shows the impact of the genetic algorithms for LFC about multiple areas connected power systems based on different wind power using in the tuning of such a process.
文摘As English serves as an international language(or Lingua Franca),increasing attention is paid to English pedagogy of English as International Language(EIL).This essay maintains that international mutual intelligibility is a more practical and achievable goal in English pronunciation pedagogy,compared with native-like proficiency and various of standard English.Meanwhile,Jenkins(2000)’s Lingua Franca Core(LFC),a Phonological Core for EIL,is briefly introduced.
基金This paper was funded by the Cultural Affairs and Missions Sector of the Egyptian Ministry of Higher Education.
文摘With rapidly growing of Renewable Energy Sources(RESs)in renewable power systems,several disturbances influence on the power systems such as;lack of system inertia that results from replacing the synchronous generators with RESs and frequency/voltage fluctuations that resulting from the intermittent nature of the RESs.Hence,the modern power systems become more susceptible to the system instability than conventional power systems.Therefore,in this study,a new application of Superconducting Magnetic Energy Storage(SMES)(i.e.,auxiliary Load Frequency Control(LFC))has been integrated with the secondary frequency control(i.e.,LFC)for frequency stability enhancement of the Egyptian Power System(EPS)due to high RESs penetration.Where,the coordinated control strategy is based on the PI controller that is optimally designed by the Particle Swarm Optimization(PSO)algorithm to minimize the frequency deviations of the EPS.The EPS includes both conventional generation units(i.e.,non-reheat,reheat and hydraulic power plants)with inherent nonlinearities,and RESs(i.e.,wind and solar energy).System modelling and simulation results are carried out using Matlab/Simulink^(■)software.The simulation results reveal the robustness of the proposed coordinated control strategy to preserve the system stability of the EPS with high penetration of RESs for different contingencies.
