以崇明岛智能电网为例,提出了风燃协调等效电厂(wind-gas coordinating equivalent power plant,WGPP)的概念。通过风力发电系统与燃气-蒸汽联合循环机组(CCPP)的互补运行,实现提高并网功率的可控和可调性,以及风燃联合发电作为一个等...以崇明岛智能电网为例,提出了风燃协调等效电厂(wind-gas coordinating equivalent power plant,WGPP)的概念。通过风力发电系统与燃气-蒸汽联合循环机组(CCPP)的互补运行,实现提高并网功率的可控和可调性,以及风燃联合发电作为一个等效电厂参与系统的调度运行等目标。针对WGPP的调度目标以及接入系统规模的不同,提出了两种不同的WGPP调度模式:跟踪调度曲线模式和CPS控制模式。为了充分利用WGPP中CCPP机组出力调节速度快的特点,对基于传统比例积分原理的自动发电控制算法进行了改进。最后,分别以现场实测数据以及四种风电功率事件为例,RTDS仿真验证了两种WGPP调度模式的可行性。展开更多
In this paper, a parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative （FP＋FI＋FD） controller is proposed. It is derived from the conventional parallel proportional-integral-derivative （PID） contr...In this paper, a parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative （FP＋FI＋FD） controller is proposed. It is derived from the conventional parallel proportional-integral-derivative （PID） controller. It preserves the linear structure of a conventional parallel PID controller, with analytical formulas. The final shape of the controller is a discrete-time fuzzy version of a conventional parallel PID controller. Computer simulations are performed to evaluate the performance of the FP＋FI＋FD controller for setpoint tracking and load-disturbance rejection for some complex processes, such as first- and second-order processes with delay, inverse response process with and without delay and higher order processes. Also, the performance of the proposed fuzzy controller is evaluated experimentally on highly nonlinear liquid-flow process with a hysteresis characteristic due to a pneumatic control valve. The simulation and real time control is done using National InstrumentTM hardware and software （LabVIEWTM）. The response of the FP＋FI＋FD controller is compared with the conventional parallel PID controller, tuned with the Ziegler-Nichols （Z-H） and /~strSm- H^gglund （A-H） tuning technique. It is observed that the FP＋FI＋FD controller performed much better than the conventional PI/PID controller. Simulation and experimental results demonstrate the effectiveness of the proposed parallel FP＋FI＋FD controller.展开更多
The paper addresses the adaptive behaviour of parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative (FP+FI+FD) controller. The parallel FP+FI+FD controller is actually a non-linear adaptive controller ...The paper addresses the adaptive behaviour of parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative (FP+FI+FD) controller. The parallel FP+FI+FD controller is actually a non-linear adaptive controller whose gain changes continuously with output of the process under control. Two non-stationary processes, whose characteristics change with time, are considered for simulation study. Simulation is performed using software LabVIEW TM . The set-point tracking response of parallel FP+FI+FD is compared with conventional parallel proportional plus integral plus derivative (PID) controller, tuned with the Ziegler-Nichols (Z-N) tuning technique. Simulation results show that conventional PID controller fails to track the set-point and becomes unstable as the process changes its characteristic with time. But the parallel FP+FI+FD controller shows considerably much better set-point tracking response and does not deviate from steady state. Also, a huge spike is observed in the output of PID controller as the reference set-point and process parameters are changed, while the FP+FI+FD controller gives spike free control signal.展开更多
The study presented in this paper is in continuation with the paper published by the authors on parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative （FP ＋ FI ＋ FD） controller. It addresses the sta...The study presented in this paper is in continuation with the paper published by the authors on parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative （FP ＋ FI ＋ FD） controller. It addresses the stability analysis of parallel FP ＋ FI ＋ FD controller. The famous＂small gain theorem＂ is used to study the bounded-input and bounded-output （BIBO） stability of the fuzzy controller. Sufficient BIBO-stability conditions are developed for parallel FP ＋ FI ＋ FD controller. FP ＋ FI ＋ FD controller is derived from the conventional parallel proportional plus integral plus derivative （PID） controller. The parallel FP ＋ FI ＋ FD controller is actually a nonlinear controller with variable gains. It shows much better set-point tracking, disturbance rejection and noise suppression for nonlinear processes as compared to conventional PID controller.展开更多
This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “com...This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “computer-automated control system design” (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process.展开更多
Proportional and derivative kick i.e., a large change in control action of a proportional plus integral plus derivative （PID） controller due to a sudden change in reference set-point is generally undesired in proces...Proportional and derivative kick i.e., a large change in control action of a proportional plus integral plus derivative （PID） controller due to a sudden change in reference set-point is generally undesired in process industry. Therefore, the structure of conventional parallel PID controller is modified to integral minus proportional derivative （I-PD） controller. In this paper, three hybrid fuzzy IPD controllers such as a fuzzy I-fuzzy PD （FI-FPD） controller and its hybrid combinations with its conventional counterpart such as fuzzy I-PD （FI-PD） and I-fuzzy PD （I-FPD） are presented in view of above industrial problem. These controllers are based upon the counterpart conventional I-PD controller and contains analytical formulae. Computer simulations are carried out to evaluate the performance of hybrid fuzzy controllers along with conventional I-PD and PID controllers for set-point tracking and disturbance rejection for an induction motor in closed loop using LabVIEWTM environment. The gains of conventional and hybrid fuzzy controllers are tuned using genetic algorithm （GA） for minimum overshoot and settling time. It has been observed that hybrid fuzzy controllers along with the conventional I-PD controller significantly remove the kick from the control action in reference set-point tracking. However, in disturbance rejection, I-PD and FI-PD controllers fail to eliminate the kick from the control signal. In contrast, FI-FPD and I-FPD controllers considerably reduced spikes from the control action in disturbance rejection. Among the conventional and hybrid fuzzy IPD controllers, FI--FPD demonstrates much better set-point tracking and disturbance rejection response with spike free control action.展开更多
三电平有源电力滤波器(APF,active power filter)系统在负载不同的情况下,谐波补偿性能的稳定性较差,通过分析三电平APF的基本工作原理,给出了一种重复-模糊PI控制方法;该方法通过瞬时无功功率理论的谐波检测将负载电流中的基波电流分离...三电平有源电力滤波器(APF,active power filter)系统在负载不同的情况下,谐波补偿性能的稳定性较差,通过分析三电平APF的基本工作原理,给出了一种重复-模糊PI控制方法;该方法通过瞬时无功功率理论的谐波检测将负载电流中的基波电流分离,然后利用重复-模糊PI控制器控制基波电流与负载电流的误差信号;采用MATLAB/Simulink进行仿真分析,发现相比于重复控制和模糊PI控制方法,重复-模糊PI控制的三电平APF结构在不同频点的跟踪稳定性得到了提升,降低了入网谐波含量,即总谐波失真(THD,total harmonic distortion);该方法可应用在工商业负载场合,弥补了模糊PI控制和重复控制单独使用时系统性能受负载变化影响的缺点,提高了其鲁棒性。展开更多
文摘以崇明岛智能电网为例,提出了风燃协调等效电厂(wind-gas coordinating equivalent power plant,WGPP)的概念。通过风力发电系统与燃气-蒸汽联合循环机组(CCPP)的互补运行,实现提高并网功率的可控和可调性,以及风燃联合发电作为一个等效电厂参与系统的调度运行等目标。针对WGPP的调度目标以及接入系统规模的不同,提出了两种不同的WGPP调度模式:跟踪调度曲线模式和CPS控制模式。为了充分利用WGPP中CCPP机组出力调节速度快的特点,对基于传统比例积分原理的自动发电控制算法进行了改进。最后,分别以现场实测数据以及四种风电功率事件为例,RTDS仿真验证了两种WGPP调度模式的可行性。
文摘In this paper, a parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative （FP＋FI＋FD） controller is proposed. It is derived from the conventional parallel proportional-integral-derivative （PID） controller. It preserves the linear structure of a conventional parallel PID controller, with analytical formulas. The final shape of the controller is a discrete-time fuzzy version of a conventional parallel PID controller. Computer simulations are performed to evaluate the performance of the FP＋FI＋FD controller for setpoint tracking and load-disturbance rejection for some complex processes, such as first- and second-order processes with delay, inverse response process with and without delay and higher order processes. Also, the performance of the proposed fuzzy controller is evaluated experimentally on highly nonlinear liquid-flow process with a hysteresis characteristic due to a pneumatic control valve. The simulation and real time control is done using National InstrumentTM hardware and software （LabVIEWTM）. The response of the FP＋FI＋FD controller is compared with the conventional parallel PID controller, tuned with the Ziegler-Nichols （Z-H） and /~strSm- H^gglund （A-H） tuning technique. It is observed that the FP＋FI＋FD controller performed much better than the conventional PI/PID controller. Simulation and experimental results demonstrate the effectiveness of the proposed parallel FP＋FI＋FD controller.
文摘The paper addresses the adaptive behaviour of parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative (FP+FI+FD) controller. The parallel FP+FI+FD controller is actually a non-linear adaptive controller whose gain changes continuously with output of the process under control. Two non-stationary processes, whose characteristics change with time, are considered for simulation study. Simulation is performed using software LabVIEW TM . The set-point tracking response of parallel FP+FI+FD is compared with conventional parallel proportional plus integral plus derivative (PID) controller, tuned with the Ziegler-Nichols (Z-N) tuning technique. Simulation results show that conventional PID controller fails to track the set-point and becomes unstable as the process changes its characteristic with time. But the parallel FP+FI+FD controller shows considerably much better set-point tracking response and does not deviate from steady state. Also, a huge spike is observed in the output of PID controller as the reference set-point and process parameters are changed, while the FP+FI+FD controller gives spike free control signal.
文摘The study presented in this paper is in continuation with the paper published by the authors on parallel fuzzy proportional plus fuzzy integral plus fuzzy derivative （FP ＋ FI ＋ FD） controller. It addresses the stability analysis of parallel FP ＋ FI ＋ FD controller. The famous＂small gain theorem＂ is used to study the bounded-input and bounded-output （BIBO） stability of the fuzzy controller. Sufficient BIBO-stability conditions are developed for parallel FP ＋ FI ＋ FD controller. FP ＋ FI ＋ FD controller is derived from the conventional parallel proportional plus integral plus derivative （PID） controller. The parallel FP ＋ FI ＋ FD controller is actually a nonlinear controller with variable gains. It shows much better set-point tracking, disturbance rejection and noise suppression for nonlinear processes as compared to conventional PID controller.
文摘This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “computer-automated control system design” (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process.
文摘Proportional and derivative kick i.e., a large change in control action of a proportional plus integral plus derivative （PID） controller due to a sudden change in reference set-point is generally undesired in process industry. Therefore, the structure of conventional parallel PID controller is modified to integral minus proportional derivative （I-PD） controller. In this paper, three hybrid fuzzy IPD controllers such as a fuzzy I-fuzzy PD （FI-FPD） controller and its hybrid combinations with its conventional counterpart such as fuzzy I-PD （FI-PD） and I-fuzzy PD （I-FPD） are presented in view of above industrial problem. These controllers are based upon the counterpart conventional I-PD controller and contains analytical formulae. Computer simulations are carried out to evaluate the performance of hybrid fuzzy controllers along with conventional I-PD and PID controllers for set-point tracking and disturbance rejection for an induction motor in closed loop using LabVIEWTM environment. The gains of conventional and hybrid fuzzy controllers are tuned using genetic algorithm （GA） for minimum overshoot and settling time. It has been observed that hybrid fuzzy controllers along with the conventional I-PD controller significantly remove the kick from the control action in reference set-point tracking. However, in disturbance rejection, I-PD and FI-PD controllers fail to eliminate the kick from the control signal. In contrast, FI-FPD and I-FPD controllers considerably reduced spikes from the control action in disturbance rejection. Among the conventional and hybrid fuzzy IPD controllers, FI--FPD demonstrates much better set-point tracking and disturbance rejection response with spike free control action.
文摘三电平有源电力滤波器(APF,active power filter)系统在负载不同的情况下,谐波补偿性能的稳定性较差,通过分析三电平APF的基本工作原理,给出了一种重复-模糊PI控制方法;该方法通过瞬时无功功率理论的谐波检测将负载电流中的基波电流分离,然后利用重复-模糊PI控制器控制基波电流与负载电流的误差信号;采用MATLAB/Simulink进行仿真分析,发现相比于重复控制和模糊PI控制方法,重复-模糊PI控制的三电平APF结构在不同频点的跟踪稳定性得到了提升,降低了入网谐波含量,即总谐波失真(THD,total harmonic distortion);该方法可应用在工商业负载场合,弥补了模糊PI控制和重复控制单独使用时系统性能受负载变化影响的缺点,提高了其鲁棒性。
