A novel three-phase active power filter (APF) circuit with photovoltaic (PV) system to improve the quality of service and to reduce the capacity of energy storage capacitor is presented. The energy balance concept...A novel three-phase active power filter (APF) circuit with photovoltaic (PV) system to improve the quality of service and to reduce the capacity of energy storage capacitor is presented. The energy balance concept and sampling technique were used to simplify the calculation algorithm for the required utility source current and to control the voltage of the energy storage capacitor. The feasibility was verified by using the Pspice simulations and experiments. When the APF mode was used during non-operational period, not only the utilization rate, power factor and power quality could be improved, but also the capacity of energy storage capacitor could sparing. As the results, the advantages of the APF circuit are simplicity of control circuits, low cost, and good transient response.展开更多
A novel dual-loop technique was proposed for single-mode selection in an optoelectronic oscillator (OEO). It consisted of a pump laser and a feedback circuit including an intensity modulator, a Fabry-Perot (FP) et...A novel dual-loop technique was proposed for single-mode selection in an optoelectronic oscillator (OEO). It consisted of a pump laser and a feedback circuit including an intensity modulator, a Fabry-Perot (FP) etalon, two optical fiber delay lines, two photodetectors, and an amplifier. By inserting the Fabry-Perot etalon, the proposed dual-loop OEO realized a single mode oscillation ranging from 0 Hz to 20 GHz. The strong oscillation mode was present at 15 GHz, and the side modes suppression ratio (SMSR) exceeded 140dB. More over the length of the two fiber loops were just 5 meters and 36 meters.展开更多
文摘A novel three-phase active power filter (APF) circuit with photovoltaic (PV) system to improve the quality of service and to reduce the capacity of energy storage capacitor is presented. The energy balance concept and sampling technique were used to simplify the calculation algorithm for the required utility source current and to control the voltage of the energy storage capacitor. The feasibility was verified by using the Pspice simulations and experiments. When the APF mode was used during non-operational period, not only the utilization rate, power factor and power quality could be improved, but also the capacity of energy storage capacitor could sparing. As the results, the advantages of the APF circuit are simplicity of control circuits, low cost, and good transient response.
文摘A novel dual-loop technique was proposed for single-mode selection in an optoelectronic oscillator (OEO). It consisted of a pump laser and a feedback circuit including an intensity modulator, a Fabry-Perot (FP) etalon, two optical fiber delay lines, two photodetectors, and an amplifier. By inserting the Fabry-Perot etalon, the proposed dual-loop OEO realized a single mode oscillation ranging from 0 Hz to 20 GHz. The strong oscillation mode was present at 15 GHz, and the side modes suppression ratio (SMSR) exceeded 140dB. More over the length of the two fiber loops were just 5 meters and 36 meters.