A rectifier circuit for wireless energy harvesting(WEH) with a wide input power range is proposed in this paper. We build up accurate models of the diodes to improve the accuracy of the design of the rectifier. Due to...A rectifier circuit for wireless energy harvesting(WEH) with a wide input power range is proposed in this paper. We build up accurate models of the diodes to improve the accuracy of the design of the rectifier. Due to the nonlinear characteristics of the diodes, a new band-stop structure is introduced to reduce the imaginary part impedance and suppress harmonics. A novel structure with double branches and an optimized λ/4 microstrip line is proposed to realize the power division ratio adjustment by the input power automatically. The proposed two branches can satisfy the two cases with input power of-20 dBm to 0 dBm and 0 dBm to 15 dBm, respectively. Here, dBm = 10 log(P mW), and P represents power. An impedance compression network(ICN) is correspondingly designed to maintain the input impedance stability over the wide input power range. A rectifier that works at 2.45 GHz is implemented. The measured results show that the highest efficiency can reach 51.5% at the output power of 0 dBm and higher than 40% at the input power of-5 dBm to 12 dBm.展开更多
This paper presents a PFCVF (Power Factor Correction) rectifier that uses a variable frequency source for alternators for electric and hybrid vehicles application. In such application, the frequency of the signal in t...This paper presents a PFCVF (Power Factor Correction) rectifier that uses a variable frequency source for alternators for electric and hybrid vehicles application. In such application, the frequency of the signal in the alternator changes according to the vehicle speed, more over the loading effect on the alternator introduces harmonic currents and increases the alternator apparent power requirements. To overcome these problems and aiming more stability and better design of the alternator, a new third harmonic injection technique is proposed. This technique allows to preserve a good THD (Total Harmonic Distortion) of the input source at any frequency and to decrease losses in semiconductors switches, thereby allowing more stability and reducing the apparent power requirements. A comparative study between the standard and the new technique is made and highlights the effectiveness of the new design. A detailed analysis of the proposed topology is presented and simulations as well as experimental results are shown.展开更多
The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and alloys.Both the single-phase and three-phase alternating current diagram with bifilar and mon...The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and alloys.Both the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot manufacturing.The numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and discussed.At the bifilar diagram of power supply,the geometrical location of electrodes in a mould holds critical importance for performances:the close location of bifilar pair electrodes provides the highest heat productivity,but the equidistant location of electrodes gives a much more uniform heat distribution.The monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.展开更多
This paper presents a new current conveyor (CCII+) full-wave rectifier for low frequency/small signal medical applications. The proposed rectifier is based on the current conveyor full-wave rectifier proposed previous...This paper presents a new current conveyor (CCII+) full-wave rectifier for low frequency/small signal medical applications. The proposed rectifier is based on the current conveyor full-wave rectifier proposed previously, but the proposed rectifier is better in view of no need diodes to rectify, and no need bias sources to overcome the zero crossing error. It needs only two CCII+s, two resistors, and three simple current mirrors, which is easy for IC implementation and for building in many countries. The PSPICE simulation with the current conveyor CCII+ in the current feedback opamp AD844 IC and the 2N2222 bipolar current mirror shows the good low frequency/small signal rectification, the operation voltage of down to 6 .展开更多
A new precision full-wave rectifier employing only two differential difference current conveyors, which is very suitable for CMOS technology implementation, is presented. The proposed rectifier is the voltage-mode cir...A new precision full-wave rectifier employing only two differential difference current conveyors, which is very suitable for CMOS technology implementation, is presented. The proposed rectifier is the voltage-mode circuit, which offers high-input and low-output impedance hence it can be directly connected to load without using any buffer circuits. PSPICE is used to verify the circuit performance. Simulated rectifier results based-on a 0.5 μm CMOS technology with ±2.5 V supply voltage demonstrates high precision rectification and excellent temperature stability. In addition, the application of proposed rectifier to pseudo RMS-to-DC conversion is also introduced.展开更多
The unique features of ambipolar two-dimensional materials open up a great opportunity to build gate-programmable devices for reconfigurable circuit applications,e.g.,PN junctions for rectifier circuits.However,curren...The unique features of ambipolar two-dimensional materials open up a great opportunity to build gate-programmable devices for reconfigurable circuit applications,e.g.,PN junctions for rectifier circuits.However,current-reported rectifier circuits usually consist of one gate-programmable PN junction as the rectifier and one resistor as the load,which are not conductive to voltage output and large-scale integration.Here we propose an approach of complementary gate-programmable PN junctions to assemble reconfigurable rectifier circuit,which include two symmetric back-to-back black phosphorus(BP)/hexagonal boron nitride(h-BN)/graphene heterostructured semi-gate field-effect transistors(FETs)and perform complementary NP and PN junction like complementary metal-oxide-semiconductor(CMOS)circuit.The investigation exhibits that the circuit can effectively reconfigure the circuit with/without rectifying ability,and can process alternating current(AC)signals with the frequency prior 1 KHz and reconfiguration speed up to 25μs.We also achieve the reconfigurable rectifier circuit memory via complementary semi-floating gate FETs configuration.The complementary configuration here should be of low output impedance and low static power consumption,being beneficial for effective voltage output and large-scale integration.展开更多
In this paper,a grid voltage sensorless model predictive control is proposed and verified by simulation and experimental tests for a PWM rectifier.The presented method is simple and cost effective due to no need of mo...In this paper,a grid voltage sensorless model predictive control is proposed and verified by simulation and experimental tests for a PWM rectifier.The presented method is simple and cost effective due to no need of modulator and voltage sensors.The developed sliding mode voltage observer(SMVO)can theoretically track the grid voltage accurately without phase lag and magnitude error.Based on the proposed SMVO,the finite control set-model predictive control(FCS-MPC)is incorporated for power regulation.The active power and reactive power are calculated and predicted using the measured current and the estimated grid voltage from the SMVO.With the predicated power for one-step delay compensation,the best voltage vector minimizing the tracking error is selected by FCS-MPC.The whole algorithm is implemented in stationary frame without using Park's transformation.Both the simulation and experimental results validate the effectiveness of the proposed method.展开更多
基金Key Laboratory of Chinese Academy of Sciences Foundation,China(No. 20190918)。
文摘A rectifier circuit for wireless energy harvesting(WEH) with a wide input power range is proposed in this paper. We build up accurate models of the diodes to improve the accuracy of the design of the rectifier. Due to the nonlinear characteristics of the diodes, a new band-stop structure is introduced to reduce the imaginary part impedance and suppress harmonics. A novel structure with double branches and an optimized λ/4 microstrip line is proposed to realize the power division ratio adjustment by the input power automatically. The proposed two branches can satisfy the two cases with input power of-20 dBm to 0 dBm and 0 dBm to 15 dBm, respectively. Here, dBm = 10 log(P mW), and P represents power. An impedance compression network(ICN) is correspondingly designed to maintain the input impedance stability over the wide input power range. A rectifier that works at 2.45 GHz is implemented. The measured results show that the highest efficiency can reach 51.5% at the output power of 0 dBm and higher than 40% at the input power of-5 dBm to 12 dBm.
文摘This paper presents a PFCVF (Power Factor Correction) rectifier that uses a variable frequency source for alternators for electric and hybrid vehicles application. In such application, the frequency of the signal in the alternator changes according to the vehicle speed, more over the loading effect on the alternator introduces harmonic currents and increases the alternator apparent power requirements. To overcome these problems and aiming more stability and better design of the alternator, a new third harmonic injection technique is proposed. This technique allows to preserve a good THD (Total Harmonic Distortion) of the input source at any frequency and to decrease losses in semiconductors switches, thereby allowing more stability and reducing the apparent power requirements. A comparative study between the standard and the new technique is made and highlights the effectiveness of the new design. A detailed analysis of the proposed topology is presented and simulations as well as experimental results are shown.
文摘The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and alloys.Both the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot manufacturing.The numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and discussed.At the bifilar diagram of power supply,the geometrical location of electrodes in a mould holds critical importance for performances:the close location of bifilar pair electrodes provides the highest heat productivity,but the equidistant location of electrodes gives a much more uniform heat distribution.The monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.
文摘This paper presents a new current conveyor (CCII+) full-wave rectifier for low frequency/small signal medical applications. The proposed rectifier is based on the current conveyor full-wave rectifier proposed previously, but the proposed rectifier is better in view of no need diodes to rectify, and no need bias sources to overcome the zero crossing error. It needs only two CCII+s, two resistors, and three simple current mirrors, which is easy for IC implementation and for building in many countries. The PSPICE simulation with the current conveyor CCII+ in the current feedback opamp AD844 IC and the 2N2222 bipolar current mirror shows the good low frequency/small signal rectification, the operation voltage of down to 6 .
文摘A new precision full-wave rectifier employing only two differential difference current conveyors, which is very suitable for CMOS technology implementation, is presented. The proposed rectifier is the voltage-mode circuit, which offers high-input and low-output impedance hence it can be directly connected to load without using any buffer circuits. PSPICE is used to verify the circuit performance. Simulated rectifier results based-on a 0.5 μm CMOS technology with ±2.5 V supply voltage demonstrates high precision rectification and excellent temperature stability. In addition, the application of proposed rectifier to pseudo RMS-to-DC conversion is also introduced.
基金Authors acknowledge the financial supports from the Ministry of Science and Technology of China(No.2018YFE0118300)the National Key Research and Development Program of China(No.2018YFA0703703)+1 种基金the State Key Laboratory of ASIC&System(No.2021MS003)the Science and Technology Commission of Shanghai Municipality(No.20501130100).
文摘The unique features of ambipolar two-dimensional materials open up a great opportunity to build gate-programmable devices for reconfigurable circuit applications,e.g.,PN junctions for rectifier circuits.However,current-reported rectifier circuits usually consist of one gate-programmable PN junction as the rectifier and one resistor as the load,which are not conductive to voltage output and large-scale integration.Here we propose an approach of complementary gate-programmable PN junctions to assemble reconfigurable rectifier circuit,which include two symmetric back-to-back black phosphorus(BP)/hexagonal boron nitride(h-BN)/graphene heterostructured semi-gate field-effect transistors(FETs)and perform complementary NP and PN junction like complementary metal-oxide-semiconductor(CMOS)circuit.The investigation exhibits that the circuit can effectively reconfigure the circuit with/without rectifying ability,and can process alternating current(AC)signals with the frequency prior 1 KHz and reconfiguration speed up to 25μs.We also achieve the reconfigurable rectifier circuit memory via complementary semi-floating gate FETs configuration.The complementary configuration here should be of low output impedance and low static power consumption,being beneficial for effective voltage output and large-scale integration.
文摘In this paper,a grid voltage sensorless model predictive control is proposed and verified by simulation and experimental tests for a PWM rectifier.The presented method is simple and cost effective due to no need of modulator and voltage sensors.The developed sliding mode voltage observer(SMVO)can theoretically track the grid voltage accurately without phase lag and magnitude error.Based on the proposed SMVO,the finite control set-model predictive control(FCS-MPC)is incorporated for power regulation.The active power and reactive power are calculated and predicted using the measured current and the estimated grid voltage from the SMVO.With the predicated power for one-step delay compensation,the best voltage vector minimizing the tracking error is selected by FCS-MPC.The whole algorithm is implemented in stationary frame without using Park's transformation.Both the simulation and experimental results validate the effectiveness of the proposed method.
