High-voltage power supply (HVPS) of Electron Cyclotron Resonance Heating (ECRH) for HT-7 and HT-7U is presently being constructed. The high voltage (100 kV) energy of HVPS is stored in the capacitor banks, and they ca...High-voltage power supply (HVPS) of Electron Cyclotron Resonance Heating (ECRH) for HT-7 and HT-7U is presently being constructed. The high voltage (100 kV) energy of HVPS is stored in the capacitor banks, and they can power one or two gyrotrons. All the operation of the charging system will be done by the control system, where the field signals are interfaced to programmable logic controller (PLC). The use of PLC not only simplifies the control system, but also enhances the reliability. The software written by using configuration software installed in the master computer allows for remote and multiple operator control, and the status and data information is also remotely available.展开更多
The system uses Japanese Mitsubishi PLC as the main control core,and intermediate relay is used for signal acquisition and conversion.The system is mainly composed of data processing module,municipal electricity monit...The system uses Japanese Mitsubishi PLC as the main control core,and intermediate relay is used for signal acquisition and conversion.The system is mainly composed of data processing module,municipal electricity monitoring module,wireless communication module,remote controller,speech recognition module,display module,sensor,switching output module and UPS power supply. The system can automatically start generator for power supply when municipal electricity is failure; when municipal electricity returns to normal,it automatically restores the power supply function of municipal electricity. In order to improve the stability of the system,the system has the functions of fault alarm,remote reset and remote query,etc.,which can realize seamless switching of municipal electricity and generator. It effectively avoids meteorological data loss,data delay,network interruption,etc. caused by unstable municipal electricity,solves the power supply problem of grass-roots meteorological station,especially at night,provides stable power supply for the integrated meteorological observation,forecasting,and early warning service.展开更多
In this paper, a mathematical analysis of the EMI (Electromagnetic Interference) for a 20 kHz/10 kV capacitor charging power supply in frequency-domain is presented, and a related circuit model considering the transie...In this paper, a mathematical analysis of the EMI (Electromagnetic Interference) for a 20 kHz/10 kV capacitor charging power supply in frequency-domain is presented, and a related circuit model considering the transient switching interference is proposed. Due to the high working frequency and the device-switching transitions, the conducted EMI caused by the charging circuit which includes the harmonics of grid frequency, working frequency and device-switching transition frequencies. Thus under certain working situations or loads parallel power supply, the interference may cause charging failure. To solve this problem, a high frequency transformer modeled with stray capacitances and an approximation of the device-switching transition is applied in the Spice-based simulation model, and a mathematical analysis in frequency-domain is presented.展开更多
With the coordinated development of today's social economy with science and technology,various advanced technologies are being used in highway engineering,especially the distributed intelligent power supply techno...With the coordinated development of today's social economy with science and technology,various advanced technologies are being used in highway engineering,especially the distributed intelligent power supply technology in expressway tunnels,which has a very significant advantage.In order to realize the effective application of this technology and promote the power supply effect in expressway tunnel,this study analyzes the advantages of this technology and its application in expressway tunnel,hoping to provide scientific reference for the application of distributed intelligent power supply technology and the engineering development of expressway tunnels.展开更多
This research analyses the operation of a solar PV powered electric vehicle charging station with energy storage, that has been developed and demonstrated at the University of California--Davis, West Village, the larg...This research analyses the operation of a solar PV powered electric vehicle charging station with energy storage, that has been developed and demonstrated at the University of California--Davis, West Village, the largest planned zero-energy consumption community in the U.S. The intelligent energy management approach introduces solar PV electrical energy forecasting and EV (electric vehicle) charging demand projection to optimize the SOC (state of charge) of the buffer battery. The charging station has been operated continuously and routinely used by several EV users for a year. The actual operation shows that, a workplace charging station equipped with a buffer battery and with intelligent energy management can lower and reduce the station's peak power demand, and reduce the energy exchange with the utility grid by a factor of 2. The battery recharging power demand was shifted away from the on-peak time periods to the off-peak time periods, which will benefit the charging station owner from less energy use during peak periods when time-of-use rates are higher. The standard cell voltage deviation of the 220 cells was calculated to analyse the battery cell consistency during the resting, charging and discharging periods. The analysis shows that, the 220 50Ah cells show excellent voltage consistency with voltage deviation of less than 0.005 V within the battery SOC of 20%-80%. The voltage deviation doubles when the battery SOC reaches 90%. The comparison of cell voltage deviation at the beginning and after one year operation indicates that, the battery shows perfect cell voltage consistency and there is no obvious consistency deterioration during the battery resting, charging and discharging periods.展开更多
This paper proposes the design concept of a dynamic charging system for electric vehicles using multiple transmitter coils connected to a common radio frequency(RF)feeder driven by a pair of two power supplies.Using a...This paper proposes the design concept of a dynamic charging system for electric vehicles using multiple transmitter coils connected to a common radio frequency(RF)feeder driven by a pair of two power supplies.Using a common RF feeder for multiple transmitter coils reduces the power electronic redundancy compared to a conventional system,where each transmitter coil is individually driven by one switched-mode power supply.Currently,wireless charging of electric vehicles is recommended to operate in the frequency range of 85 kHz and beyond.In this frequency range,the signal wavelength is shorter than about 3.5 km.Therefore,a charging pad longer than several hundred meters is subject to the standing wave effect.In such a case,the voltage significantly varies along the RF feeder,resulting in a variation in the received power level when the receiver moves.Specifically,the received power significantly deteriorates when the receiver is nearby a node of the voltage standing wave.In this paper,we employ a pair of two power sources which are electrically separated by an odd-integer number of the quarter wavelength to drive the RF feeder.As a result,the voltage standing wave generated by one power source is complemented by that of the other,leading to stable received power and transmission efficiency at all the receiver’s positions along with the charging pad.Simulation results at the 85 kHz frequency band verify the output power stabilization effect of the proposed design.It is worth noting that the proposed concept can also be applied to simultaneous wireless information and power transfer(SWIPT)for passive radio frequency identification(RFID)tags by raising the operation frequency to higher industrial,scientific and medical(ISM)bands,e.g.,13.56 MHz and employing similar modulation methods as in the current RFID technology.展开更多
A power management unit (PMU) chip supplying dual panel supply voltage, which has a low electro-magnetic interference (EMI) characteristic and is favorable for miniaturization, is designed. A two-phase charge pump...A power management unit (PMU) chip supplying dual panel supply voltage, which has a low electro-magnetic interference (EMI) characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip's 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.展开更多
The electric unmanned aerial vehicles (UAVs) are rapidly growing due to their abilities to perform some difficult or dangerous tasks as well as many public services including real-time monitoring, wireless coverage, s...The electric unmanned aerial vehicles (UAVs) are rapidly growing due to their abilities to perform some difficult or dangerous tasks as well as many public services including real-time monitoring, wireless coverage, search and rescue, wildlife surveys, and precision agriculture. However, the electrochemical power supply system of UAV is a critical issue in terms of its energy/power densities and lifetime for service endurance. In this paper, the current power supply systems used in UAVs are comprehensively reviewed and analyzed on the existing power configurations and the energy management systems. It is identified that a single type of electrochemical power source is not enough to support a UAV to achieve a long-haul flight;hence, a hybrid power system architecture is necessary. To make use of the advantages of each type of power source to increase the endurance and achieve good performance of the UAVs, the hybrid systems containing two or three types of power sources (fuel cell,battery, solar cell, and supercapacitor,) have to be developed. In this regard, the selection of an appropriate hybrid power structure with the optimized energy management system is critical for the efficient operation of a UAV. It is found that the data-driven models with artificial intelligence (AI) are promising in intelligent energy management. This paper can provide insights and guidelines for future research and development into the design and fabrication of the advanced UAV power systems.展开更多
基金The project supported by the National Meg-science Engineering Project of the Chinese Government
文摘High-voltage power supply (HVPS) of Electron Cyclotron Resonance Heating (ECRH) for HT-7 and HT-7U is presently being constructed. The high voltage (100 kV) energy of HVPS is stored in the capacitor banks, and they can power one or two gyrotrons. All the operation of the charging system will be done by the control system, where the field signals are interfaced to programmable logic controller (PLC). The use of PLC not only simplifies the control system, but also enhances the reliability. The software written by using configuration software installed in the master computer allows for remote and multiple operator control, and the status and data information is also remotely available.
基金Supported by Youth Technology Foundation Item of Guizhou Meteorological Bureau in 2015(QN201520)
文摘The system uses Japanese Mitsubishi PLC as the main control core,and intermediate relay is used for signal acquisition and conversion.The system is mainly composed of data processing module,municipal electricity monitoring module,wireless communication module,remote controller,speech recognition module,display module,sensor,switching output module and UPS power supply. The system can automatically start generator for power supply when municipal electricity is failure; when municipal electricity returns to normal,it automatically restores the power supply function of municipal electricity. In order to improve the stability of the system,the system has the functions of fault alarm,remote reset and remote query,etc.,which can realize seamless switching of municipal electricity and generator. It effectively avoids meteorological data loss,data delay,network interruption,etc. caused by unstable municipal electricity,solves the power supply problem of grass-roots meteorological station,especially at night,provides stable power supply for the integrated meteorological observation,forecasting,and early warning service.
文摘In this paper, a mathematical analysis of the EMI (Electromagnetic Interference) for a 20 kHz/10 kV capacitor charging power supply in frequency-domain is presented, and a related circuit model considering the transient switching interference is proposed. Due to the high working frequency and the device-switching transitions, the conducted EMI caused by the charging circuit which includes the harmonics of grid frequency, working frequency and device-switching transition frequencies. Thus under certain working situations or loads parallel power supply, the interference may cause charging failure. To solve this problem, a high frequency transformer modeled with stray capacitances and an approximation of the device-switching transition is applied in the Spice-based simulation model, and a mathematical analysis in frequency-domain is presented.
文摘With the coordinated development of today's social economy with science and technology,various advanced technologies are being used in highway engineering,especially the distributed intelligent power supply technology in expressway tunnels,which has a very significant advantage.In order to realize the effective application of this technology and promote the power supply effect in expressway tunnel,this study analyzes the advantages of this technology and its application in expressway tunnel,hoping to provide scientific reference for the application of distributed intelligent power supply technology and the engineering development of expressway tunnels.
文摘This research analyses the operation of a solar PV powered electric vehicle charging station with energy storage, that has been developed and demonstrated at the University of California--Davis, West Village, the largest planned zero-energy consumption community in the U.S. The intelligent energy management approach introduces solar PV electrical energy forecasting and EV (electric vehicle) charging demand projection to optimize the SOC (state of charge) of the buffer battery. The charging station has been operated continuously and routinely used by several EV users for a year. The actual operation shows that, a workplace charging station equipped with a buffer battery and with intelligent energy management can lower and reduce the station's peak power demand, and reduce the energy exchange with the utility grid by a factor of 2. The battery recharging power demand was shifted away from the on-peak time periods to the off-peak time periods, which will benefit the charging station owner from less energy use during peak periods when time-of-use rates are higher. The standard cell voltage deviation of the 220 cells was calculated to analyse the battery cell consistency during the resting, charging and discharging periods. The analysis shows that, the 220 50Ah cells show excellent voltage consistency with voltage deviation of less than 0.005 V within the battery SOC of 20%-80%. The voltage deviation doubles when the battery SOC reaches 90%. The comparison of cell voltage deviation at the beginning and after one year operation indicates that, the battery shows perfect cell voltage consistency and there is no obvious consistency deterioration during the battery resting, charging and discharging periods.
基金JSPS KAKENHI under Grant Nos.20K14736 and 19K04376.
文摘This paper proposes the design concept of a dynamic charging system for electric vehicles using multiple transmitter coils connected to a common radio frequency(RF)feeder driven by a pair of two power supplies.Using a common RF feeder for multiple transmitter coils reduces the power electronic redundancy compared to a conventional system,where each transmitter coil is individually driven by one switched-mode power supply.Currently,wireless charging of electric vehicles is recommended to operate in the frequency range of 85 kHz and beyond.In this frequency range,the signal wavelength is shorter than about 3.5 km.Therefore,a charging pad longer than several hundred meters is subject to the standing wave effect.In such a case,the voltage significantly varies along the RF feeder,resulting in a variation in the received power level when the receiver moves.Specifically,the received power significantly deteriorates when the receiver is nearby a node of the voltage standing wave.In this paper,we employ a pair of two power sources which are electrically separated by an odd-integer number of the quarter wavelength to drive the RF feeder.As a result,the voltage standing wave generated by one power source is complemented by that of the other,leading to stable received power and transmission efficiency at all the receiver’s positions along with the charging pad.Simulation results at the 85 kHz frequency band verify the output power stabilization effect of the proposed design.It is worth noting that the proposed concept can also be applied to simultaneous wireless information and power transfer(SWIPT)for passive radio frequency identification(RFID)tags by raising the operation frequency to higher industrial,scientific and medical(ISM)bands,e.g.,13.56 MHz and employing similar modulation methods as in the current RFID technology.
文摘A power management unit (PMU) chip supplying dual panel supply voltage, which has a low electro-magnetic interference (EMI) characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip's 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.
基金supported in part by the founding of state key laboratory of industrial control technology,Zhejiang University(ICT2021B19)the Technological Innovation and Application Demonstration in Chongqing(Major Themes of Industry:cstc2019jscx-zdztzxX0033,cstc2019jscxfxyd0158)the National Natural Science Foundation of China(NO.22005026,21908142).
文摘The electric unmanned aerial vehicles (UAVs) are rapidly growing due to their abilities to perform some difficult or dangerous tasks as well as many public services including real-time monitoring, wireless coverage, search and rescue, wildlife surveys, and precision agriculture. However, the electrochemical power supply system of UAV is a critical issue in terms of its energy/power densities and lifetime for service endurance. In this paper, the current power supply systems used in UAVs are comprehensively reviewed and analyzed on the existing power configurations and the energy management systems. It is identified that a single type of electrochemical power source is not enough to support a UAV to achieve a long-haul flight;hence, a hybrid power system architecture is necessary. To make use of the advantages of each type of power source to increase the endurance and achieve good performance of the UAVs, the hybrid systems containing two or three types of power sources (fuel cell,battery, solar cell, and supercapacitor,) have to be developed. In this regard, the selection of an appropriate hybrid power structure with the optimized energy management system is critical for the efficient operation of a UAV. It is found that the data-driven models with artificial intelligence (AI) are promising in intelligent energy management. This paper can provide insights and guidelines for future research and development into the design and fabrication of the advanced UAV power systems.