Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic ...Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic capacitance. Using this model, computerized simulation is conducted for the FB - ZVZCS - PWM soft - ewitching converter,the switching and energy-transferring characteristics of the components are analyzed.The simulation results are testified by experiments.It is proved that by abopting appropriate models,computerized simulation becomes an effective tool for investigation of arc welding inverter power source.展开更多
A novel inverter power source is developed characterized with constant output current and unit power factor input. Digital signal processor （ DSP ） is used to realize power factor correction and control of back-stag...A novel inverter power source is developed characterized with constant output current and unit power factor input. Digital signal processor （ DSP ） is used to realize power factor correction and control of back-stage inverter bridge of the arc welding inverter. The fore-stage adopts double closed loop proportion and integration （PI） rectifier technique and the back- stage adopts digital pulse width modulation （ PWM） technique. Simulated waves can be obtained in Matlab/Simulink and validated by experiments. Experiments of the prototype showed that the total harmonic distortion （THD） can be controlled within 10% and the power factor is approximate to 1.展开更多
The FB-ZVZCS-PWM converter is realized by the way of subjoiningblock-capacitor into the FB-ZVS-PWM converter. At the freewheeling interval, the primary current isattenuated fast to zero and maintained. And then, power...The FB-ZVZCS-PWM converter is realized by the way of subjoiningblock-capacitor into the FB-ZVS-PWM converter. At the freewheeling interval, the primary current isattenuated fast to zero and maintained. And then, power device of the static leg becomes azero-current-switch (ZCS), power device of the shifted leg becomes a zero-voltage-switch(ZVS). Thus,on one hand IGBT (Insulated gate bipolar transistor) with tail current can be easily used infull-bridge soft-switching converter; on the other hand additional circuiting energy is greatlyreduced. At the same time, less duty cycle loss, lower secondary parasitic resonance, widersoft-switching load range can be achieved. Based on the existing component models in the Pspicesoftware package, a combined model of IGBT is established, in which a non-linear capacitor isintroduced to replace the parasitic capacitor. Using this model, computerized simulation isconducted for the FB-ZVZCS-PWM soft-switching converter, the switching and energy-transferringcharacteristics of the power device are analyzed. Finally, based on the achievement above, a 10 kWarc welding inverter with FB-ZVZCS-PWM converter is developed. The simulation results are testifiedby experiments. It is proved that by adopting appropriate models, computerized simulation is aneffective and useful tool for the development of the arc welding inverter.展开更多
It is very difficult for arc welding inverter to realize Zero-Voltage-Switching （ZVS） because the load of arc welding inverter changes violently. An improved PS-FB-ZVS-PWM （ Phase-Shifted Full-Bridge Zero-Voltage-S...It is very difficult for arc welding inverter to realize Zero-Voltage-Switching （ZVS） because the load of arc welding inverter changes violently. An improved PS-FB-ZVS-PWM （ Phase-Shifted Full-Bridge Zero-Voltage-Switching Pulse-Width-Modulation） topology is proposed in this paper. A saturate resonant inductor is in series with the primary side of the transformer, while an auxiliary inductor is in parallel with the secondary side of the transformer to increase reactive current in light load or unload state, so the zero voltage switching of power devices is realized during switching course in light load or unload state.展开更多
A digital control of pulsed gas metal arc welding inverter was proposed. A control system consisting of analogue parts was replaced with a new digital control implemented in a TMS320LF2407A DSP chip. The design and co...A digital control of pulsed gas metal arc welding inverter was proposed. A control system consisting of analogue parts was replaced with a new digital control implemented in a TMS320LF2407A DSP chip. The design and constructional features of the whole digital control were presented. The resources of the DSP chip were efficiently utilized and the circuits are very concise, which can enhance the stability and reliability of welding inverter. Experimental results demonstrate that the developed digital control has the ability to accomplish the excellent pulsed gas metal arc welding process and the merits of the developed digital control are stable welding process, little spatter and perfect weld appearance.展开更多
The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topolo...The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topology of soft-switching inverter arc welding power supplies. However, the output power still remains a certain value when the duty-cycle of leading arm decreases to zero. The working-mode of soft-switching inverter and the waveforms of major parameters with the condition of duty-cycle of leading arm being zero are studied in this paper. U-1 characteristic experiments prove that the minimum output power of soft-switching circuit, which depends on the charged voltage of capacitors in parallel with leading arm, can be decreased by reducing the duty-cycle of lagging arm. By switching working-modes between half-bridge and full-bridge, the output power can swing from zero to the power rating.展开更多
A small-signal model of current programmed mode pulse width modulation converter including the equivalent sampling effect is introduced and analyzed. In this model, an addition pole is brought out by the sampling effe...A small-signal model of current programmed mode pulse width modulation converter including the equivalent sampling effect is introduced and analyzed. In this model, an addition pole is brought out by the sampling effect in the current loop gain, and it affects dynamic bandwidth and stability of the inner current loop. By selecting the appropriate stability parameter which determines the additional pole and describes the degree of peaking in closed loop transfer function, a control model of current programmed full bridge arc welding inverter with maximum frequency bandwidth and stability can be obtained. Small and large amplitude pulse current outputs are employed in simulations and experiments and results validate the design method.展开更多
The soft switching are welding inverter reduces switching losses and improves operating environment of devices by using Zero-Voltage-Transition (ZVT) technique. Step-by-step analysis of each timing interval and the as...The soft switching are welding inverter reduces switching losses and improves operating environment of devices by using Zero-Voltage-Transition (ZVT) technique. Step-by-step analysis of each timing interval and the associating voltage and current waveforms are included for the Full-Bridge Zero-Voltage-Switched PWM converter. Numerous design equations supporting the phase-shifted soft switching technique are highlighted.展开更多
The full bridge zero voltage zero current switching （ FB-ZVZCS ） , which could adjust the output power by keeping the duty ratio of lagging leg constant and changing the duty ratio of leading leg, was a common circu...The full bridge zero voltage zero current switching （ FB-ZVZCS ） , which could adjust the output power by keeping the duty ratio of lagging leg constant and changing the duty ratio of leading leg, was a common circuit of soft switching arc welding inverter power source. However, when the duty ratio of leading leg was reduced to zero, the output power stayed the constant value instead of becoming zero. The working status and waveforms of some major parameters were studied in this paper while the duty ratio of leading leg was zero. It was concluded that the minimum output power of soft switching inverter was related to the charging voltage of paraUel capacitors, and the output power also could be reduced by reducing the duty ratio of lagging leg. A novel two-stage continuous PWM control method that could switch working-mode between full bridge and half bridge was put forward in this paper. This kind of control method could further reduce the output power of soft switching inverter in order to meet the requirement of low heat input of sheet metal welding.展开更多
This paper mainly introduces an output control method with high stable precision of a large power IGBT arc welding inverter. Experiments indicate that this kind of control mode can effectively improve the static and d...This paper mainly introduces an output control method with high stable precision of a large power IGBT arc welding inverter. Experiments indicate that this kind of control mode can effectively improve the static and dynamic characteristics and stability of power supply system. And it can decrease the spatters in the welding process apparently. This power supply is especially suitable to automatic robot welding assembly line. It will be the developing direction of robot welding supply in the future.展开更多
A fuzzy logic intelligent control system of pulsed MAG welding inverter based on digital signal processor （DSP） is proposed to obtain the consistency of arc length in pulsed MAG welding. The proposed control system ...A fuzzy logic intelligent control system of pulsed MAG welding inverter based on digital signal processor （DSP） is proposed to obtain the consistency of arc length in pulsed MAG welding. The proposed control system combines the merits of intelligent control with DSP digital control. The fuzzy logic intelligent control system designed is a typical two-input-single-output structure, and regards the error and the change in error of peak arc voltage as two inputs and the background time as single output. The fuzzy logic intelligent control system is realized in a look-up table （LUT） method by using MATLAB based fuzzy logic toolbox, and the implement of LUT method based on DSP is also discussed. The pulsed MAG welding experimental results demonstrate that the developed fuzzy logic intelligent control system based on DSP has strong arc length controlling ability to accomplish the stable pulsed MAG welding process and controls pulsed MAG welding inverter digitally and intelligently.展开更多
Full bridge Zero Voltage Switch PWM converter combines advantages of the PWM control technique and resonant technique. However, Full ZVS is achieved only under large load current because resonant tank of this circu...Full bridge Zero Voltage Switch PWM converter combines advantages of the PWM control technique and resonant technique. However, Full ZVS is achieved only under large load current because resonant tank of this circuit is made up of the parasitic capacitance of the power semiconductors and the leakage inductor of the transformer primary. In this paper two saturable inductors as magnetic switches are added to secondary, so output inductor is always reflected to primary and assists resonant transition. Full ZVS is achieved under lower load current. The above mentioned investigated results are validated by the computerized simulation and hardware circuit experiment.展开更多
An inverter type power source system for robot arc welding is considered. The power source includes several isolated gate bipolar transistor (IGBT) inverter power units. The output current of every individual power un...An inverter type power source system for robot arc welding is considered. The power source includes several isolated gate bipolar transistor (IGBT) inverter power units. The output current of every individual power unit is regulated by an identical single chip microcomputer to enable the whole power source system to work over a wide range of continuous output current with good dynamic properties. This inverter type power source satisfies robotic welding requirements.展开更多
文摘Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic capacitance. Using this model, computerized simulation is conducted for the FB - ZVZCS - PWM soft - ewitching converter,the switching and energy-transferring characteristics of the components are analyzed.The simulation results are testified by experiments.It is proved that by abopting appropriate models,computerized simulation becomes an effective tool for investigation of arc welding inverter power source.
文摘A novel inverter power source is developed characterized with constant output current and unit power factor input. Digital signal processor （ DSP ） is used to realize power factor correction and control of back-stage inverter bridge of the arc welding inverter. The fore-stage adopts double closed loop proportion and integration （PI） rectifier technique and the back- stage adopts digital pulse width modulation （ PWM） technique. Simulated waves can be obtained in Matlab/Simulink and validated by experiments. Experiments of the prototype showed that the total harmonic distortion （THD） can be controlled within 10% and the power factor is approximate to 1.
基金This project is supported by National Natural Science Foundation of China(No.50075003)Municipal Natural Science Foundation of Beijing, China(No.3001001).
文摘The FB-ZVZCS-PWM converter is realized by the way of subjoiningblock-capacitor into the FB-ZVS-PWM converter. At the freewheeling interval, the primary current isattenuated fast to zero and maintained. And then, power device of the static leg becomes azero-current-switch (ZCS), power device of the shifted leg becomes a zero-voltage-switch(ZVS). Thus,on one hand IGBT (Insulated gate bipolar transistor) with tail current can be easily used infull-bridge soft-switching converter; on the other hand additional circuiting energy is greatlyreduced. At the same time, less duty cycle loss, lower secondary parasitic resonance, widersoft-switching load range can be achieved. Based on the existing component models in the Pspicesoftware package, a combined model of IGBT is established, in which a non-linear capacitor isintroduced to replace the parasitic capacitor. Using this model, computerized simulation isconducted for the FB-ZVZCS-PWM soft-switching converter, the switching and energy-transferringcharacteristics of the power device are analyzed. Finally, based on the achievement above, a 10 kWarc welding inverter with FB-ZVZCS-PWM converter is developed. The simulation results are testifiedby experiments. It is proved that by adopting appropriate models, computerized simulation is aneffective and useful tool for the development of the arc welding inverter.
文摘It is very difficult for arc welding inverter to realize Zero-Voltage-Switching （ZVS） because the load of arc welding inverter changes violently. An improved PS-FB-ZVS-PWM （ Phase-Shifted Full-Bridge Zero-Voltage-Switching Pulse-Width-Modulation） topology is proposed in this paper. A saturate resonant inductor is in series with the primary side of the transformer, while an auxiliary inductor is in parallel with the secondary side of the transformer to increase reactive current in light load or unload state, so the zero voltage switching of power devices is realized during switching course in light load or unload state.
基金Supported by National Natural Science Foundation of China ( No50375054)China Postdoctoral Science Foundation ( No20060400745)
文摘A digital control of pulsed gas metal arc welding inverter was proposed. A control system consisting of analogue parts was replaced with a new digital control implemented in a TMS320LF2407A DSP chip. The design and constructional features of the whole digital control were presented. The resources of the DSP chip were efficiently utilized and the circuits are very concise, which can enhance the stability and reliability of welding inverter. Experimental results demonstrate that the developed digital control has the ability to accomplish the excellent pulsed gas metal arc welding process and the merits of the developed digital control are stable welding process, little spatter and perfect weld appearance.
文摘The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topology of soft-switching inverter arc welding power supplies. However, the output power still remains a certain value when the duty-cycle of leading arm decreases to zero. The working-mode of soft-switching inverter and the waveforms of major parameters with the condition of duty-cycle of leading arm being zero are studied in this paper. U-1 characteristic experiments prove that the minimum output power of soft-switching circuit, which depends on the charged voltage of capacitors in parallel with leading arm, can be decreased by reducing the duty-cycle of lagging arm. By switching working-modes between half-bridge and full-bridge, the output power can swing from zero to the power rating.
文摘A small-signal model of current programmed mode pulse width modulation converter including the equivalent sampling effect is introduced and analyzed. In this model, an addition pole is brought out by the sampling effect in the current loop gain, and it affects dynamic bandwidth and stability of the inner current loop. By selecting the appropriate stability parameter which determines the additional pole and describes the degree of peaking in closed loop transfer function, a control model of current programmed full bridge arc welding inverter with maximum frequency bandwidth and stability can be obtained. Small and large amplitude pulse current outputs are employed in simulations and experiments and results validate the design method.
文摘The soft switching are welding inverter reduces switching losses and improves operating environment of devices by using Zero-Voltage-Transition (ZVT) technique. Step-by-step analysis of each timing interval and the associating voltage and current waveforms are included for the Full-Bridge Zero-Voltage-Switched PWM converter. Numerous design equations supporting the phase-shifted soft switching technique are highlighted.
文摘The full bridge zero voltage zero current switching （ FB-ZVZCS ） , which could adjust the output power by keeping the duty ratio of lagging leg constant and changing the duty ratio of leading leg, was a common circuit of soft switching arc welding inverter power source. However, when the duty ratio of leading leg was reduced to zero, the output power stayed the constant value instead of becoming zero. The working status and waveforms of some major parameters were studied in this paper while the duty ratio of leading leg was zero. It was concluded that the minimum output power of soft switching inverter was related to the charging voltage of paraUel capacitors, and the output power also could be reduced by reducing the duty ratio of lagging leg. A novel two-stage continuous PWM control method that could switch working-mode between full bridge and half bridge was put forward in this paper. This kind of control method could further reduce the output power of soft switching inverter in order to meet the requirement of low heat input of sheet metal welding.
文摘This paper mainly introduces an output control method with high stable precision of a large power IGBT arc welding inverter. Experiments indicate that this kind of control mode can effectively improve the static and dynamic characteristics and stability of power supply system. And it can decrease the spatters in the welding process apparently. This power supply is especially suitable to automatic robot welding assembly line. It will be the developing direction of robot welding supply in the future.
基金supported by National Natural Science Foundation of China(No.50375054)China Postdoctoral Science Foundation (No.20060400745).
文摘A fuzzy logic intelligent control system of pulsed MAG welding inverter based on digital signal processor （DSP） is proposed to obtain the consistency of arc length in pulsed MAG welding. The proposed control system combines the merits of intelligent control with DSP digital control. The fuzzy logic intelligent control system designed is a typical two-input-single-output structure, and regards the error and the change in error of peak arc voltage as two inputs and the background time as single output. The fuzzy logic intelligent control system is realized in a look-up table （LUT） method by using MATLAB based fuzzy logic toolbox, and the implement of LUT method based on DSP is also discussed. The pulsed MAG welding experimental results demonstrate that the developed fuzzy logic intelligent control system based on DSP has strong arc length controlling ability to accomplish the stable pulsed MAG welding process and controls pulsed MAG welding inverter digitally and intelligently.
文摘Full bridge Zero Voltage Switch PWM converter combines advantages of the PWM control technique and resonant technique. However, Full ZVS is achieved only under large load current because resonant tank of this circuit is made up of the parasitic capacitance of the power semiconductors and the leakage inductor of the transformer primary. In this paper two saturable inductors as magnetic switches are added to secondary, so output inductor is always reflected to primary and assists resonant transition. Full ZVS is achieved under lower load current. The above mentioned investigated results are validated by the computerized simulation and hardware circuit experiment.
文摘An inverter type power source system for robot arc welding is considered. The power source includes several isolated gate bipolar transistor (IGBT) inverter power units. The output current of every individual power unit is regulated by an identical single chip microcomputer to enable the whole power source system to work over a wide range of continuous output current with good dynamic properties. This inverter type power source satisfies robotic welding requirements.
