The photovoltaic (PV) generator exhibits a nonlinear current-voltage (I-V) characteristic that its maximum power point (MPP) varies with solar insolation. In this paper, a maximum power point tracking (MPPT) method us...The photovoltaic (PV) generator exhibits a nonlinear current-voltage (I-V) characteristic that its maximum power point (MPP) varies with solar insolation. In this paper, a maximum power point tracking (MPPT) method using fuzzy logic control (FLC) is presented. This method is based on the concept of perturbation and observation (P & O) algorithm to track the MPP of a stand-alone PV system. The controller is used to maximize the power generated by the PV array and the simulation of the system is implemented in MATLAB. Simulation results are compared with those obtained by the conventional P & O controller. Results show that the FLC gives better and more reliable control for the stand-alone PV system feeding hybrid loads.展开更多
Nowadays,AC electronic loads with energy recovery are widely used in the testing of uninterruptible power supplies and power supply equipment.To tackle the problems of control difficulty,strategy complexity,and poor d...Nowadays,AC electronic loads with energy recovery are widely used in the testing of uninterruptible power supplies and power supply equipment.To tackle the problems of control difficulty,strategy complexity,and poor dynamic performance of AC electronic load with energy recovery of the conventional control strategy,a control strategy of AC electronic load with energy recovery based on Finite Control Set Model Predictive Control(FCSMPC)is developed.To further reduce the computation burden of the FCS-MPC,a simplified FCS-MPC with transforming the predicted variables and using sector to select expected state is proposed.Through simplified model and equivalent approximation analysis,the transfer function of the system is obtained,and the stability and robustness of the system are analyzed.The performance of the simplified FCS-MPC is compared with space vector control(SVPWM)and conventional FCS-MPC.The results show that the FCS-MPC method performs better dynamic response and this advantage is more obvious when simulating high power loads.The simplified FCS-MPC shows similar control performance to conventional FCS-MPC at less computation burden.The control performance of the system also shows better simulation results.展开更多
Triggered vacuum switches(TVSs)have fast growing applications in the field of power system and pulse power.The relation between triggering parameters of triggering system,such as triggering voltage and triggering powe...Triggered vacuum switches(TVSs)have fast growing applications in the field of power system and pulse power.The relation between triggering parameters of triggering system,such as triggering voltage and triggering power,between the triggering time delay and its scatter of TVS had been obtained through series of experiments.The result can be adopted as the steering for high-power controller design and application of TVS.A steepened high-voltage triggering pulse is introduced in the main high-voltage generating circuit.As a result,the triggering time delay and its scatter can be decreased remarkably.Synchronous switch technology is imported to control the triggering phase at the crest of applied voltage on TVS.The Triggering characteristic of TVS under alternating current(AC)and direct current(DC)load has been investigated emphatically.Given the identical triggering parameter of triggering system,DC condition is prior to AC on the triggering probability and stability markedly.Such conclusion can be drawn,for AC condition,TVS would require much for the triggering system.展开更多
电力弹簧(electric spring,ES)作为一种电能质量优化装置,对关键负载与非关键负载进行区分使得电力弹簧在对关键负载进行保护时,非关键负载无法运行在其额定电压下,而且其调压能力受到线路参数的限制。针对传统ES在实际电网中工作时的...电力弹簧(electric spring,ES)作为一种电能质量优化装置,对关键负载与非关键负载进行区分使得电力弹簧在对关键负载进行保护时,非关键负载无法运行在其额定电压下,而且其调压能力受到线路参数的限制。针对传统ES在实际电网中工作时的被动性,文中提出一种基于双极性直接式AC-AC变换器的主动电力弹簧(AC-AC based active electric spring,AC-AES)实现分布式调压。AC-AES不再对关键负载与非关键负载进行区分,对用户负载进行统一控制,从而使其调压变得主动。最后,通过仿真和实验分别验证所提装置通过调节电压调控负载功率的可行性,以及在波动电网中稳定负载电压的能力。展开更多
文摘The photovoltaic (PV) generator exhibits a nonlinear current-voltage (I-V) characteristic that its maximum power point (MPP) varies with solar insolation. In this paper, a maximum power point tracking (MPPT) method using fuzzy logic control (FLC) is presented. This method is based on the concept of perturbation and observation (P & O) algorithm to track the MPP of a stand-alone PV system. The controller is used to maximize the power generated by the PV array and the simulation of the system is implemented in MATLAB. Simulation results are compared with those obtained by the conventional P & O controller. Results show that the FLC gives better and more reliable control for the stand-alone PV system feeding hybrid loads.
文摘Nowadays,AC electronic loads with energy recovery are widely used in the testing of uninterruptible power supplies and power supply equipment.To tackle the problems of control difficulty,strategy complexity,and poor dynamic performance of AC electronic load with energy recovery of the conventional control strategy,a control strategy of AC electronic load with energy recovery based on Finite Control Set Model Predictive Control(FCSMPC)is developed.To further reduce the computation burden of the FCS-MPC,a simplified FCS-MPC with transforming the predicted variables and using sector to select expected state is proposed.Through simplified model and equivalent approximation analysis,the transfer function of the system is obtained,and the stability and robustness of the system are analyzed.The performance of the simplified FCS-MPC is compared with space vector control(SVPWM)and conventional FCS-MPC.The results show that the FCS-MPC method performs better dynamic response and this advantage is more obvious when simulating high power loads.The simplified FCS-MPC shows similar control performance to conventional FCS-MPC at less computation burden.The control performance of the system also shows better simulation results.
基金This work was carried out under the support of Guangxi Key Laboratory of Manufacturing System and Advanced Manufacturing Technology(No.0842006_025_Z).
文摘Triggered vacuum switches(TVSs)have fast growing applications in the field of power system and pulse power.The relation between triggering parameters of triggering system,such as triggering voltage and triggering power,between the triggering time delay and its scatter of TVS had been obtained through series of experiments.The result can be adopted as the steering for high-power controller design and application of TVS.A steepened high-voltage triggering pulse is introduced in the main high-voltage generating circuit.As a result,the triggering time delay and its scatter can be decreased remarkably.Synchronous switch technology is imported to control the triggering phase at the crest of applied voltage on TVS.The Triggering characteristic of TVS under alternating current(AC)and direct current(DC)load has been investigated emphatically.Given the identical triggering parameter of triggering system,DC condition is prior to AC on the triggering probability and stability markedly.Such conclusion can be drawn,for AC condition,TVS would require much for the triggering system.
文摘电力弹簧(electric spring,ES)作为一种电能质量优化装置,对关键负载与非关键负载进行区分使得电力弹簧在对关键负载进行保护时,非关键负载无法运行在其额定电压下,而且其调压能力受到线路参数的限制。针对传统ES在实际电网中工作时的被动性,文中提出一种基于双极性直接式AC-AC变换器的主动电力弹簧(AC-AC based active electric spring,AC-AES)实现分布式调压。AC-AES不再对关键负载与非关键负载进行区分,对用户负载进行统一控制,从而使其调压变得主动。最后,通过仿真和实验分别验证所提装置通过调节电压调控负载功率的可行性,以及在波动电网中稳定负载电压的能力。
