Plasma electric source deviceTechnical field
The present invention relates to power technique fields more particularly to a kind of power supply devices for plasma apparatus.
Background technique
Plasma apparatus has been more and more widely used in fields such as washing, cutting, welding, such as using high-precision etc.Ion-cleaning equipment cleans semiconductor and LCD display, optical equipment, PCB, sheet etc. high-precision to realizeIt is required that the plasma gas torch power for washing is 2000W-10000W, operating voltage 6-15KV belongs to powerful device.
The prior art is the L (Reactor) increased that the transformer inputs of atmospheric plasma power supply device are additionalPerhaps C (Capacitor) L (Reactor) or C (Capacitor) are connected in series or in parallel, after keeping it variable, when useWith the characteristic of gas torch, the method for power density is passively adjusted.With load (gas torch) temperature change, the characteristic variations of thermalizationWith the wear problem of the passage of time, heat is caused to increase, efficiency reduction, load inherent parameters (such as capacitor, impedance) becomesChange causes the efficiency of power supply to reduce, output density reduces, and needs the L by manual adjustment transformer inputs at this time(Reactor) or C (Capacitor) value promotes power-efficient, will be unable to the temperature characterisitic etc. of reply L, C in this wayVariation, therefore have high power density output limitation.It is led in addition, it is necessary to install contact relay and power network switch M/C etc.The service life for sending a telegraph source device is low.
Summary of the invention
In order to solve the above problem existing for existing plasma electric source device, the present invention provides a kind of high density electrical powerThe plasma electric source device of output.
Present invention technical solution used for the above purpose is: plasma electric source device, including AC power source AC,Rectification circuit, boost chopper, inverter circuit and transformer, AC power source connect the defeated of the rectification circuit being made of diodeEntering end, rectification circuit output end connects the input terminal of boost chopper, and the output end of boost chopper connects inverter circuit,The output end of inverter circuit connects transformer, and the output end of transformer connects load；The electric current of AC power source AC passes through rectified currentRoad is converted into DC current, and the DC current of rectification circuit output passes through after boosting and eliminating delay by boost chopperInverter circuit converts exchange for direct current and is conveyed to transformer, according to the variation of load or power-efficient to the switch of inverter circuitFrequency and impulse amplitude are controlled to improve power-efficient.
Capacitor C is connected in series in the transformer inputs.
The load is that gas torch or DBD are loaded.
Plasma electric source device of the invention can pass through control in the case where the passive components such as no capacitor, inductanceThe frequency and impulse amplitude of inverter switch promote electromotive power output density, load (gas torch) thermalization, aging and causeImpedance and capacitor variation when also can produce the output of high electrical power density；Additionally, due to unused power converterRelay etc., extend the service life of power supply device, reduce costs.
Detailed description of the invention
Fig. 1 is plasma power supply device circuit schematic diagram of the present invention.
Fig. 2 is plasma power supply rating of set density schematic diagram calculation of the present invention.
When Fig. 3 is that plasma electric source device exports high electrical power density, voltage, current waveform figure.
When Fig. 4 is plasma electric source device output low electric power density, voltage, current waveform figure.
Fig. 5 is that plasma power supply Installation practice one of the present invention controls rate-adaptive pacemaker by the control inverter switching device timeVoltage, current waveform figure.
Fig. 6 is that plasma power supply Installation practice two of the present invention controls rate-adaptive pacemaker by the control inverter switching device timeVoltage, current waveform figure.
Fig. 7 is that plasma power supply Installation practice three of the present invention controls impulse amplitude by the control inverter switching device timeVoltage, the current waveform figure of output.
Fig. 8 is that plasma power supply Installation practice four of the present invention controls impulse amplitude by the control inverter switching device timeVoltage, current waveform figure.
Specific embodiment
Plasma electric source device of the invention can be used for gas torch or powerful DBD (Dielectric BarrierDischarge, plasma generator) load, as plasma washing facility gas torch, plasma cutting machine, plasma welding machine orPlasma air purification and water purification system etc., circuit is as shown in Figure 1, include AC power source AC, rectification circuit, boost chopper electricityRoad, inverter circuit and transformer, AC is transformed to DC by rectifier diode by power input, then in order to which D/C voltage is boosted,In order to highly boost, the input terminal of transformer is inverter.Physical circuit is as follows: AC power source connection is made of whole diodeThe input terminal of current circuit, rectification circuit output end connect the input terminal of boost chopper, and boost chopper is by inductance LBoost、Triode SBoost, Diode and CLinkIt constitutes, the output end of boost chopper connects inverter circuit, the output end of inverter circuitTransformer is connected, transformer inputs are connected in series capacitor C and are used for pressure stabilizing and current stabilization, and the output end of transformer connects load；It hands overThe electric current of galvanic electricity source AC is converted into DC current by rectification circuit, and the DC current of rectification circuit output passes through boost chopper electricityExchange is converted for direct current by inverter circuit after the boosting of road and is conveyed to transformer.
As shown in Fig. 2, installing current inductor and voltage sensor to input by the input terminal in boost chopperElectric current and voltage are acquired, to calculate input power；Electricity is installed respectively by the input terminal and output end in transformerStream inductor and voltage sensor are acquired output electric current and voltage, to calculate output power, output power with it is defeatedThe ratio for entering power is the efficiency of power supply.Although efficiency can still be obtained because of the loss of power rectifier switch element etc., efficiency90% or more, it is exported for high density.
The waveform diagram of voltage and current, it is defeated to be illustrated in figure 4 low power density when being illustrated in figure 3 high power density outputThe waveform diagram of voltage and current when out.
The plasma electric source efficiency actually calculated is compared with 90%, when power-efficient is lower than 90%, control is openedThe ON/OFF time of pass, which improves frequency, will increase the time of switch opened if frequency range internal efficiency does not improve, and increaseImpulse amplitude.
Fig. 5 and Fig. 6 is respectively the voltage and current waveform diagram under inverter switching device different frequency, and Fig. 7 and Fig. 8 are different arteries and veinsRush the voltage and current waveform diagram under period and amplitude.
The present invention promotes output electric work by controlling frequency and the impulse amplitude of plasma electric source device inverter switching deviceThe thermalization state of plasma gas torch is passed through power calculation with the capacitor of plasma thermalization and the increase of impedance by rate densityMethod embodies and implements to control, and in order to improve the output of electrical power density, increases or decreases ON/OFF time and the pulse width of switchDegree output, high density output can also be carried out by being able to carry out accurate control and not needing other accessories.
The present invention is described by embodiment, and those skilled in the art know, is not departing from spirit of the inventionIn the case where range, various changes or equivalence replacement can be carried out to these features and embodiment.In addition, in religion of the inventionIt leads down, can modify to these features and embodiment to adapt to particular situation and material without departing from essence of the inventionMind and range.Therefore, the present invention is not limited to the particular embodiment disclosed, fallen with claims hereofEmbodiment in range belongs to protection scope of the present invention.