In this paper, the auto-tuning of a fractional order proportional and integral(FOPI) controller is proposed and experimentally validated for two-input two-output(TITO) processes. The proposed method first identifies a...In this paper, the auto-tuning of a fractional order proportional and integral(FOPI) controller is proposed and experimentally validated for two-input two-output(TITO) processes. The proposed method first identifies an unknown TITO plant into fractional order TITO model with time delay. Furthermore, decoupling the TITO process into two fractional order single-input single-output(SISO) transfer function models makes it easier for designing the decentralized FOPI controllers. The proposed control method is a generalization of both integer order and fractional order TITO systems depending on the value of the order of the model. One advantage of this method is the non-requirement of a-priori information of gain and phase crossover frequencies of the system while tuning the controllers. The proposed algorithm is validated both by simulation of a class of TITO process models as well as by experimental analysis of a coupled tank system(CTS).展开更多
In this paper,we report on the identification and modeling of unknown and higher order processes into first order plus dead time(FOPDT)plants based on the limit cycle information obtained from a single relay feedback ...In this paper,we report on the identification and modeling of unknown and higher order processes into first order plus dead time(FOPDT)plants based on the limit cycle information obtained from a single relay feedback test with an online fractional order proportional integral(FOPI)controller.The parameters of the test processes are accurately determined by the state space method while the FOPI controller settings are re-tuned to achieve enhanced performance based on the identified model parameters based on the balancedtuning method.A new performance index,integral time fractional order absolute error(ITFIAE)is introduced in this paper for balanced tuning of fractional order(FO)controllers.It requires minimum design specifications without a-priori knowledge of gain and phase crossover frequencies and is done non-iteratively without disrupting the closed loop.Four test processes and experimental analysis on a coupled tank system(CTS)validate the theory proposed.展开更多
This paper proposes a low complexity control scheme for voltage control of a dynamic voltage restorer(DVR)in a three-phase system.The control scheme employs the fractional order,proportional-integral-derivative(FOPID)...This paper proposes a low complexity control scheme for voltage control of a dynamic voltage restorer(DVR)in a three-phase system.The control scheme employs the fractional order,proportional-integral-derivative(FOPID)controller to improve on the DVR performance in order to enhance the power quality in terms of the response time,steady-state error and total harmonic distortion(THD).The result obtained was compared with fractional order,proportionalintegral(FOPI),proportional-integral-derivative(PID)and proportional-integral(PI)controllers in order to show the effectiveness of the proposed DVR control scheme.A water cycle optimization algorithm(WCA)was utilized to find the optimal set for all the controller gains.They were used to solve four power quality issues;balanced voltage sag,balanced voltage swell,unbalanced voltage sag,and unbalanced voltage swell.It showed that one set of controller gain obtained from the WCA could solve all the power quality issues while the others in the literature needed an individual set of optimal gain for each power quality problem.To prove the concept,the proposed DVR algorithm was simulated in the MATLAB/Simulink software and the results revealed that the four optimal controllers can compensate for all the power quality problems.A comparative analysis of the results in various aspects of their dynamic response and%THD was discussed and analyzed.It was found that PID controller yields the most rapid performance in terms of average response time while FOPID controller yields the best performance in term of average%steady-state error.FOPI controller was found to provide the lowest THD percentage in the average%THD.FOPID did not differ much in average response from the PID and average%THD from FOPI;however,FOPID provided the most outstanding average steady-state error.According to the CBMA curve,the dynamic responses of all controllers fall in the acceptable power quality area.The total harmonic distortion(THD)of the compensated load voltage from all the controllers were within the 8%limit in accordance to the IEEE std.519-2014.展开更多
In this paper, fractional order PI(FOPI) control is developed for speed control of permanent magnet synchronous motor(PMSM). Designing the parameters for FOPI controller is a challenging task, especially for nonlinear...In this paper, fractional order PI(FOPI) control is developed for speed control of permanent magnet synchronous motor(PMSM). Designing the parameters for FOPI controller is a challenging task, especially for nonlinear systems like PMSM.All three PI controllers in the conventional vector controlled speed drive are replaced by FOPI controllers. Design of these FOPI controllers is based on the locally linearized model of PMSM around an operating point. This operating point changes with the load torque. The novelty of the work reported here is in use of Non Linear Disturbance Observer(NLDO) to estimate load torque to obtain this new operating point. All three FOPI controllers are then designed adaptively using this new operating point. The scheme is tested on simulation using MATLAB/SIMULINK and results are presented.展开更多
An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.Howe...An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.However,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult issue.Fractional-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance.The suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum performance.The suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid load.The optimal FOPI+iFOPI controller manages the voltage and frequency of the load.The behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed controller.MATLAB simulations were used to evaluate the recommended system’s performance.The results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and frequency.In addition,the required load demand was accurately reduced.Furthermore,the microgrid functioned incredibly well despite SMES and varying wind speeds.Results obtained under identical conditions were compared with and without the best FOPI+iFOPI controller.When utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES.展开更多
[目的]随着集成互联网数据中心(Internet Data Center,IDC)逐步成为一种体量庞大的新兴负荷,充分挖掘IDC需求侧响应潜力有利于实现主动配电网(Active Distribution Network,ADN)的优化控制,提高配电网新能源利用率。[方法]为解决以上问...[目的]随着集成互联网数据中心(Internet Data Center,IDC)逐步成为一种体量庞大的新兴负荷,充分挖掘IDC需求侧响应潜力有利于实现主动配电网(Active Distribution Network,ADN)的优化控制,提高配电网新能源利用率。[方法]为解决以上问题,文章提出了一种基于IDC需求侧响应特性,采用分数阶比例积分(Fractional Order Proportional Integral,FOPI)与分数阶比例微分(Fractional Order Proportional Differential,FOPD)级联结构的ADN优化控制策略。首先,文章构建了一种考虑响应负载时间转移特性、空间转移特性和新能源消纳特性的功耗模型,并考虑了其需求侧响应参与ADN优化控制的建模研究;其次,结合几种控制原理设计不同优化控制策略,优化配电网能耗结构,提升新能源利用率,实现配电网的优化控制;最后,结合具有1000台服务器的贵州省某大型数据中心进行仿真分析。[结果]结果表明:相比于其他控制策略,采用FOPI-FOPD的控制策略具有更好的优化控制效果,使其运行成本降低了1.71%,峰谷差减少了21.92%,新能源利用率提升了15.78%~17.02%。[结论]仿真实验结果验证了所提优化控制策略的有效性与合理性。展开更多
Generally,the Battery Energy Storage Systems(BESS)may meet entire load requirements while the wind turbine and PV array are still not providing energy,which enhances the reliability of the power system's distribut...Generally,the Battery Energy Storage Systems(BESS)may meet entire load requirements while the wind turbine and PV array are still not providing energy,which enhances the reliability of the power system's distribution.The primary aim of the presented research is to produce a framework for enhancing power quality in hybrid devices attached to renewable sources via an optimised fractional order proportional integral(FOPI)Controller in Unified Power Quality Conditioner(UPQC).The source input is made up of RES.To address the PQ difficulties,the UPQC employs series and shunt filter management techniques.Utilizing suggested Adaptive Bald Eagle optimisation algorithm(ABE-OA),the variables are ideally optimised for greater control.To confirm the effectiveness of the proposed method in PQ enhancement,the effectiveness of the developed system is evaluated to that of previous techniques.The proposed method achieved better rise time of 2042.5 and settling min of 19,999.展开更多
文摘In this paper, the auto-tuning of a fractional order proportional and integral(FOPI) controller is proposed and experimentally validated for two-input two-output(TITO) processes. The proposed method first identifies an unknown TITO plant into fractional order TITO model with time delay. Furthermore, decoupling the TITO process into two fractional order single-input single-output(SISO) transfer function models makes it easier for designing the decentralized FOPI controllers. The proposed control method is a generalization of both integer order and fractional order TITO systems depending on the value of the order of the model. One advantage of this method is the non-requirement of a-priori information of gain and phase crossover frequencies of the system while tuning the controllers. The proposed algorithm is validated both by simulation of a class of TITO process models as well as by experimental analysis of a coupled tank system(CTS).
文摘In this paper,we report on the identification and modeling of unknown and higher order processes into first order plus dead time(FOPDT)plants based on the limit cycle information obtained from a single relay feedback test with an online fractional order proportional integral(FOPI)controller.The parameters of the test processes are accurately determined by the state space method while the FOPI controller settings are re-tuned to achieve enhanced performance based on the identified model parameters based on the balancedtuning method.A new performance index,integral time fractional order absolute error(ITFIAE)is introduced in this paper for balanced tuning of fractional order(FO)controllers.It requires minimum design specifications without a-priori knowledge of gain and phase crossover frequencies and is done non-iteratively without disrupting the closed loop.Four test processes and experimental analysis on a coupled tank system(CTS)validate the theory proposed.
基金This Research was Financially Supported by Faculty of Engineering,Mahasarakham University(Grant year 2021).
文摘This paper proposes a low complexity control scheme for voltage control of a dynamic voltage restorer(DVR)in a three-phase system.The control scheme employs the fractional order,proportional-integral-derivative(FOPID)controller to improve on the DVR performance in order to enhance the power quality in terms of the response time,steady-state error and total harmonic distortion(THD).The result obtained was compared with fractional order,proportionalintegral(FOPI),proportional-integral-derivative(PID)and proportional-integral(PI)controllers in order to show the effectiveness of the proposed DVR control scheme.A water cycle optimization algorithm(WCA)was utilized to find the optimal set for all the controller gains.They were used to solve four power quality issues;balanced voltage sag,balanced voltage swell,unbalanced voltage sag,and unbalanced voltage swell.It showed that one set of controller gain obtained from the WCA could solve all the power quality issues while the others in the literature needed an individual set of optimal gain for each power quality problem.To prove the concept,the proposed DVR algorithm was simulated in the MATLAB/Simulink software and the results revealed that the four optimal controllers can compensate for all the power quality problems.A comparative analysis of the results in various aspects of their dynamic response and%THD was discussed and analyzed.It was found that PID controller yields the most rapid performance in terms of average response time while FOPID controller yields the best performance in term of average%steady-state error.FOPI controller was found to provide the lowest THD percentage in the average%THD.FOPID did not differ much in average response from the PID and average%THD from FOPI;however,FOPID provided the most outstanding average steady-state error.According to the CBMA curve,the dynamic responses of all controllers fall in the acceptable power quality area.The total harmonic distortion(THD)of the compensated load voltage from all the controllers were within the 8%limit in accordance to the IEEE std.519-2014.
文摘In this paper, fractional order PI(FOPI) control is developed for speed control of permanent magnet synchronous motor(PMSM). Designing the parameters for FOPI controller is a challenging task, especially for nonlinear systems like PMSM.All three PI controllers in the conventional vector controlled speed drive are replaced by FOPI controllers. Design of these FOPI controllers is based on the locally linearized model of PMSM around an operating point. This operating point changes with the load torque. The novelty of the work reported here is in use of Non Linear Disturbance Observer(NLDO) to estimate load torque to obtain this new operating point. All three FOPI controllers are then designed adaptively using this new operating point. The scheme is tested on simulation using MATLAB/SIMULINK and results are presented.
基金This research was funded by the Deputyship for Research and Innovation,Ministry of Education,Saudi Arabia,through the University of Tabuk,Grant Number S-1443-0123.
文摘An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.However,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult issue.Fractional-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance.The suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum performance.The suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid load.The optimal FOPI+iFOPI controller manages the voltage and frequency of the load.The behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed controller.MATLAB simulations were used to evaluate the recommended system’s performance.The results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and frequency.In addition,the required load demand was accurately reduced.Furthermore,the microgrid functioned incredibly well despite SMES and varying wind speeds.Results obtained under identical conditions were compared with and without the best FOPI+iFOPI controller.When utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES.
文摘[目的]随着集成互联网数据中心(Internet Data Center,IDC)逐步成为一种体量庞大的新兴负荷,充分挖掘IDC需求侧响应潜力有利于实现主动配电网(Active Distribution Network,ADN)的优化控制,提高配电网新能源利用率。[方法]为解决以上问题,文章提出了一种基于IDC需求侧响应特性,采用分数阶比例积分(Fractional Order Proportional Integral,FOPI)与分数阶比例微分(Fractional Order Proportional Differential,FOPD)级联结构的ADN优化控制策略。首先,文章构建了一种考虑响应负载时间转移特性、空间转移特性和新能源消纳特性的功耗模型,并考虑了其需求侧响应参与ADN优化控制的建模研究;其次,结合几种控制原理设计不同优化控制策略,优化配电网能耗结构,提升新能源利用率,实现配电网的优化控制;最后,结合具有1000台服务器的贵州省某大型数据中心进行仿真分析。[结果]结果表明:相比于其他控制策略,采用FOPI-FOPD的控制策略具有更好的优化控制效果,使其运行成本降低了1.71%,峰谷差减少了21.92%,新能源利用率提升了15.78%~17.02%。[结论]仿真实验结果验证了所提优化控制策略的有效性与合理性。
文摘Generally,the Battery Energy Storage Systems(BESS)may meet entire load requirements while the wind turbine and PV array are still not providing energy,which enhances the reliability of the power system's distribution.The primary aim of the presented research is to produce a framework for enhancing power quality in hybrid devices attached to renewable sources via an optimised fractional order proportional integral(FOPI)Controller in Unified Power Quality Conditioner(UPQC).The source input is made up of RES.To address the PQ difficulties,the UPQC employs series and shunt filter management techniques.Utilizing suggested Adaptive Bald Eagle optimisation algorithm(ABE-OA),the variables are ideally optimised for greater control.To confirm the effectiveness of the proposed method in PQ enhancement,the effectiveness of the developed system is evaluated to that of previous techniques.The proposed method achieved better rise time of 2042.5 and settling min of 19,999.
