This paper presents two kind to pologies of newtype single-stage inverter with half-bridge and push-pull con-struction.The half-bridge single-stage DC/AC topo-logyis suited for high input voltage,and the push-pull sin...This paper presents two kind to pologies of newtype single-stage inverter with half-bridge and push-pull con-struction.The half-bridge single-stage DC/AC topo-logyis suited for high input voltage,and the push-pull single stage DC/AC topology is suited for low input voltage.The principles lf the two topologies are introduced.Ths-oretical and experimental results verify that they are suit-ed for small power DC/AC applications because of the ex-cellent performances such as simple construction,smallvolume,light weight and high reliability.展开更多
The electrolytic-capacitor-less(EL-cap-less)technique has been attracting more and more interests in these years.The EL-cap-less single-phase to three-phase inverter(STI)with front-end diode rectifier is applied to ho...The electrolytic-capacitor-less(EL-cap-less)technique has been attracting more and more interests in these years.The EL-cap-less single-phase to three-phase inverter(STI)with front-end diode rectifier is applied to home electrical appliances.In EL-cap-less systems,film-type capacitor is used to suppress the high-frequency ripple components instead of smoothing the DC-link voltage.By using the EL-cap-less solution,reliability can be improved,lifetime can be increased and high power factor(PF)also can be realized.The EL-cap-less STI brings the opportunity to simplify system structure and lower cost.Because a certain DC-link capacitance is still required,the real PF is limited.To further improve the PF,the ripple components of current references are made in synchronous with the DClink voltage.And the capacitance chosen guideline of the film-type capacitor also be presented.A prototype is built to verify its real performance.展开更多
The conventional inverters have the shortcomings of straightway conduction in transistors and the difficulty of realizing soft swit￣ching. A novel inverter based on the DC/DC converter topology is presented. The inve...The conventional inverters have the shortcomings of straightway conduction in transistors and the difficulty of realizing soft swit￣ching. A novel inverter based on the DC/DC converter topology is presented. The inverter is comprised of a combined Buck/Boost DC/DC converter and a bridge circuit. The front stage converter is controlled to output variable DC voltage and the bridge circuit is used to convert the DC voltage to AC output. The energy feedback technology and one circle control scheme are used t...展开更多
DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the pa...DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the parallel inverter system without output isolation transformers, the difference of DC components of the output voltage can cause large DC loop-current among modular inverters. Aiming at this problem, this paper studies several DC loop-current detecting and restraining methods. By digital adjustment with high precision on the DC components of reference sine wave, the DC components of inverter′s output voltage can be adjusted to restrain DC loop-current. Experimental results prove that the DC loop-current detecting and restraining methods have a good performance.展开更多
Single zinc oxide nanowires(ZnO NWs)are promising for nanogenerators because of their excellent semiconducting and piezoelectric properties,but characterizing the latter efficiently is challenging.As reported here,an ...Single zinc oxide nanowires(ZnO NWs)are promising for nanogenerators because of their excellent semiconducting and piezoelectric properties,but characterizing the latter efficiently is challenging.As reported here,an electrical breakdown strategy was used to construct single ZnO NWs with a specific length.With the high operability of a nanomanipulator in a scanning electron microscope,ZnO-NW-based twoprobe and three-probe structures were constructed for fabricating AC/DC nanogenerators,respectively.For a ZnO NW,an AC output of between−15.31 mV and 5.82 mV was achieved,while for a DC nanogenerator,an output of24.3 mV was realized.Also,the three-probe structure’s output method was changed to verify the distribution of piezoelectric charges when a single ZnO NW is bent by a probe,and DC outputs of different amplitudes were achieved.This study provides a low-cost,highly convenient,and operational method for studying the AC/DC output characteristics of single NWs,which is beneficial for the further development of nanogenerators.展开更多
This article presents an ongoing study of the design of a DC-AC inverter using a single renewable energy source. The proposed approach makes it possible to produce an output with an H-bridge or full bridge and a singl...This article presents an ongoing study of the design of a DC-AC inverter using a single renewable energy source. The proposed approach makes it possible to produce an output with an H-bridge or full bridge and a single energy source. To this end, the performance of the inverter was studied first by means of a simulation and then with the implementation of an experimental device.展开更多
The design of a general simulation package for AC drive system with soft switching inverter is discussed in this paper. This package is based on the secondary developing of the nonlinear control system simulation lang...The design of a general simulation package for AC drive system with soft switching inverter is discussed in this paper. This package is based on the secondary developing of the nonlinear control system simulation language SIMNON. Being constructed with modularization programming, the package can be used for general purposes conveuieutly and has strong graphic functions. The design principle for this simulation package is discussed in datail in this peper; and an application example (DSC controlled AC drive system with RDCLI) as well as its simulation results are given.展开更多
文摘This paper presents two kind to pologies of newtype single-stage inverter with half-bridge and push-pull con-struction.The half-bridge single-stage DC/AC topo-logyis suited for high input voltage,and the push-pull single stage DC/AC topology is suited for low input voltage.The principles lf the two topologies are introduced.Ths-oretical and experimental results verify that they are suit-ed for small power DC/AC applications because of the ex-cellent performances such as simple construction,smallvolume,light weight and high reliability.
基金supported by the Fundamental Research Funds for the Central Universities (No.NT2018011)the China Postdoctoral Science Foundation (No.2015M580424)
文摘The electrolytic-capacitor-less(EL-cap-less)technique has been attracting more and more interests in these years.The EL-cap-less single-phase to three-phase inverter(STI)with front-end diode rectifier is applied to home electrical appliances.In EL-cap-less systems,film-type capacitor is used to suppress the high-frequency ripple components instead of smoothing the DC-link voltage.By using the EL-cap-less solution,reliability can be improved,lifetime can be increased and high power factor(PF)also can be realized.The EL-cap-less STI brings the opportunity to simplify system structure and lower cost.Because a certain DC-link capacitance is still required,the real PF is limited.To further improve the PF,the ripple components of current references are made in synchronous with the DClink voltage.And the capacitance chosen guideline of the film-type capacitor also be presented.A prototype is built to verify its real performance.
文摘The conventional inverters have the shortcomings of straightway conduction in transistors and the difficulty of realizing soft swit￣ching. A novel inverter based on the DC/DC converter topology is presented. The inverter is comprised of a combined Buck/Boost DC/DC converter and a bridge circuit. The front stage converter is controlled to output variable DC voltage and the bridge circuit is used to convert the DC voltage to AC output. The energy feedback technology and one circle control scheme are used t...
文摘DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the parallel inverter system without output isolation transformers, the difference of DC components of the output voltage can cause large DC loop-current among modular inverters. Aiming at this problem, this paper studies several DC loop-current detecting and restraining methods. By digital adjustment with high precision on the DC components of reference sine wave, the DC components of inverter′s output voltage can be adjusted to restrain DC loop-current. Experimental results prove that the DC loop-current detecting and restraining methods have a good performance.
基金supported by the Research Fund Program of the Guangdong Provincial Key Laboratory of Fuel Cell Technology (Grant No.FC202204).
文摘Single zinc oxide nanowires(ZnO NWs)are promising for nanogenerators because of their excellent semiconducting and piezoelectric properties,but characterizing the latter efficiently is challenging.As reported here,an electrical breakdown strategy was used to construct single ZnO NWs with a specific length.With the high operability of a nanomanipulator in a scanning electron microscope,ZnO-NW-based twoprobe and three-probe structures were constructed for fabricating AC/DC nanogenerators,respectively.For a ZnO NW,an AC output of between−15.31 mV and 5.82 mV was achieved,while for a DC nanogenerator,an output of24.3 mV was realized.Also,the three-probe structure’s output method was changed to verify the distribution of piezoelectric charges when a single ZnO NW is bent by a probe,and DC outputs of different amplitudes were achieved.This study provides a low-cost,highly convenient,and operational method for studying the AC/DC output characteristics of single NWs,which is beneficial for the further development of nanogenerators.
文摘This article presents an ongoing study of the design of a DC-AC inverter using a single renewable energy source. The proposed approach makes it possible to produce an output with an H-bridge or full bridge and a single energy source. To this end, the performance of the inverter was studied first by means of a simulation and then with the implementation of an experimental device.
文摘The design of a general simulation package for AC drive system with soft switching inverter is discussed in this paper. This package is based on the secondary developing of the nonlinear control system simulation language SIMNON. Being constructed with modularization programming, the package can be used for general purposes conveuieutly and has strong graphic functions. The design principle for this simulation package is discussed in datail in this peper; and an application example (DSC controlled AC drive system with RDCLI) as well as its simulation results are given.
