Welder of half bridge inversion electron beam uses the design of power source of dc high pressure

Generation of the meeting when power source of switch of circuit of 1EMC filter wave works conducts noise to return subsidiary channels in the human body through which vital energy of city electrified wire netting, affect the regular job of circuit of electric source control, generate interference to the wiring of other, because this must try,overcome [2] . This power source uses circuit of EMC filter wave, the filter of road of power supply cord that basically comprises by L and C, include difference the model is restrained and in all the model restrains circuit, can check difference effectively model and in all modular noise. 2.

2 can accuse rectification circuit to be able to accuse rectification circuit to move tool set piece to comprise by compositive unifinication intelligence, inductance L1 and circuit of wave of filter of capacitance C3 composition in order to obtain relatively smooth volts d.c. , rc and Rd comprise accurate feedback sampling circuit, keep stable below the action that ensures output voltage is dominating circuit. 2.

Circuit of inversion of 3IGBT inversion circuit wait for composition by element of transformer of C of half bridge capacitance, IGBT, high pressure, protection. IGBT is the rapid series module of Fuji company, its model is 1MBH600-100. T is high-pressured transformer, the high frequency alternating voltage that the step up of transformer of high pressure of classics of square wave voltage after classics IGBT inversion controls to 40kV. Because the v/LIT all over the ground number of high-pressured coil is more, be in high frequency when, parasitism capacitance and feel oneself the output that can affect power source is characteristic [3] , because this needs pair of coil to take electrostatic screen, the action that because be opposite,additionally terrestrial electricity allows, bundle shed overlay of the meeting on sampling resistor signal of one high frequency communication [4] , must adopt compensation measure to try to eliminate. This power source uses double screen measure to eliminate bundle dry faze signal, add screen of outfit double deck between tall low-pressure coil namely, ground connection of ground floor screen, the 2nd is received in bundle shed sampling resistor. VL11, R9, C9, VL21, R19, C19 comprises the aiguille voltage of IGBT to draw circuit, ensure the safety of IGBT works. 2.

Circuit of commutate of high pressure of circuit of commutate of 4 high pressure reachs sampling circuit to comprise by resistor of capacitor of wave of filter of caboodle of silicon of high frequency high pressure, high pressure, protection. Because the voltage after step up of transformer of classics high pressure has taller frequency, choose high frequency high pressure so the need of caboodle of fast commutate silicon with commutate of contented and high frequency high pressure. Filter wave capacitor chooses high-pressured polystyrene capacitor, this kind of capacitor has lesser Tg δ and high frequency property, characteristic to the output of power source impact is little. The current limliting resistor that restricts short-circuit current and overvoltage of power source interior for effective ground and protective resistor, all collect appliance to have hot property stable, feel small oneself, stream the size is large, have stronger be able to bear or endure the hypostatic resistance that gets overvoltage, electric current to pound ability. The high-pressured sampling signal in sampling circuit is obtained by precision resistance voltage divider, voltage divider is circled by narrow line make without electrification block, coping adds outfit screen electrode, assure the stability of sampling voltage. Electron beam sheds sampling to also circle resistor to be made without touch line through nicety, resistor of two kinds of sampling all is put in electromagnetism screen box, prevent to disturb signal to enter control circuit. Circuit of control of 3 control circuit is given by PI adjust the composition such as PWM and circuit, its drive circuit. What voltage outputs after rectification controls circuit to assure town report commutate is stable. PI is given adjust circuit and PWM and the stability that its drive circuit realizes dc high pressure and self-adjusting. The working principle of each part circuit is as follows. 3.

1 commutate moves to control circuit commutate to control circuit to be compositive the generous standard inside module is controlled in tone integrated circuit. The sampling of voltage divider of resistor of volts d.c. classics after rectification sends the feedback of PI adjuster end via n segregation circuit, PI adjuster falls in the joint action that give and feedbacks, give intelligence to move tool set block control to carry via one dc signal is being outputted after enlarge, spark in order to control what brilliant brake is in charge of horn, implementation dc outputs the stable adjustment of voltage. Auxiliary power source uses power source of linear of compositive unifinication high accuracy, ground of each power source becomes independent respectively, be opposite in order to reduce signal of interference of ground electric current the influence that commands circuit. 3.

2PI is given adjust circuit PI is given adjust circuit reachs the composition such as segregation circuit by sampling of signal of adjuster of PLC and D/A module, PI, feedback. Give signal to be installed by PLC program, it was included rise inclined wave function and drop inclined wave function, module of quantity classics D/A outputs the number after operation to give potentiometer, adjust potentiometer can adjust the gives signal size of PI adjustment. Feedback signal takes the feedback end that keeps apart circuit to input PI adjuster via n from the low-pressure arm of tall precision resistance voltage divider. PI adjuster is mixed by TL494[6] in-house amplifier outside receive resistor capacitance composition, specific principle circuit is shown 3 times like the graph. 3.

If the graph is shown 3 times,the electric principle of 3PWM and PWM of its drive circuit and its drive circuit pursues. PWM signal by TL494 modulation, TL494 receives voltaic signal to had served as outside in-house another amplifier shed protection to use. The electricity that voltaic sensor uses LEM company to produce detects segregation parts of an apparatus, can assure to control the reliable segregation of circuit and main circuit, have trends to answer the characteristic with signal of electric current of fast, sampling and good degree of linearity of output electric current, the interference signal to sampling circuit effect that can overcome high-pressured circuit effectively. Feedback signal and modulation of TL494 of the classics after giving signal to adjust in PI adjuster become two complementary PWM pulse. The input of the EXB840 of special drive module that the pulse that TL494 outputs sends IGBT is carried, the drive circuit of IGBT uses the module of the 1200V of EXB840 special drive of Fuji company, 70A, interior uses 2500V photoelectricity to keep apart circuit, its input voltage to be ＋ 20V, among them ＋ 15V serves as IGBT to driving voltage, - 5V is IGBT the grid that when closing, is imposed in IGBT and blast off extremely the retrorse voltage between, those who make is reliable close. Foot 14 outside the IGBT of PWM signal drive that receives TL494 output, foot 6 receive IGBT to detect through diode of IGBT shed signal too, foot 4 outside receive control circuit shed signal to input PLC too, after PLC undertakes operation and processing to its, had given out shed signal. The signal after the working process that controls circuit is action of classics PI adjuster inputs TL494 interior, TL494 outputs PWM pulse, its occupy sky comparing to output the size of signal to decide by PI adjuster, have IGBT of the drive after the effect of EXB840 of PWM pulse classics that takes sky comparing certainly, realize transformer to output the stable adjustment of voltage thereby. When power source of high pressure of 4 protection circuit is working, the in-house meeting of power source produces overvoltage or cross power source of attaint of voltaic as a result or IGBT, because this must install protection,circuit assures the safety of power source. Power source had been installed press protection, gradient to rise reach drop circuit and shed protective circuit too. Shed protection to use 3 class protection too: The first class is EXB840 circuit itself shed protection to detect too function, flow too in IGBT namely when, the foot of IGBT drive module 6 meetings had detected shed signal and direct block outputs pulse, close IGBT, at the same time the foot of EXB840 receives circuit to output signal to give PLC outside 4 courses, after PLC passes program operation, had given out on one hand shed signal directive, to brilliant brake on the other hand the canal moves to control circuit to provide block pulse signal, guan Duanjing brake is in charge of main circuit. The foot that protection of the 2nd class is the in-house amplifier that uses TL494 15, 16 outside receive electric current to keep apart sensor, when the voltaic signal that detects exceeds set to be worth, TL494 block outputs pulse, realize pair of IGBT thereby close. Protection of the 3rd class is high-pressured side electron beam had flowed to shed protection, should have appeared when electric current, bundle shed sampling signal to feedback to dominate circuit, control circuit has been given out shed signal to give PLC, PLC is given out respectively close main circuit and shed indication signal too, had come true to shed protection thereby. Power source still had been installed press protective circuit, undertake effectively protective to the overvoltage of power source, still add in the interior of high-pressured power source mounted current limliting resistor and protective resistance, had restricted electric current and overvoltage effectively. To overcome the impact of report of the town when switching on the mobile phone to power source, through PLC interior the program installed function of the soft brae that start, PI regards as adjuster after operation of classics D/A module give, those who realize power source is soft start. The technical index of the technical index power source of system of 5 power source is as follows: Input voltage 220V, 50Hz; Output voltage 0 ～ 60kV, ％ of ripple coefficient <1, stability 10 - 4; Electron beam sheds 0 ～ 167mA, ％ of ripple coefficient <1; Go against frequency conversion to lead 20kHz; Output power 0 ～ 10kW; Efficiency > 80 ％ . 6 epilogue classics experiments, the each technology index of power source all achieved expectant design goal. Electron beam welder uses power source of inversion type high pressure with high-pressured power source, be helpful for the miniaturization of whole equipment, special apply to welder of portable electron beam, improved the use efficiency of equipment, realize interlocking to high-pressured automation protection more easily, make equipment operation more simple. Welder of high-power electron beam uses inversion power source to still need to study further with high-pressured power source. To high-power welder power source (30kW above) , bulk and specific power consumption are in opposite blame to stress the position, the protective technology when on the other hand the high pressure of high-power power source discharges, production technology of high frequency transformer, inversion control technology remain to study at further ground and be developed. As a result of dependability and power source efficiency rise, the high-pressured power source that the welder of power waits for to use this design in (3 ～ 15kW) be worth to popularize and apply. In the influence of the power source when high-pressured strike a light to low-pressure circuit, IGBT flow too and pressed the respect such as protection, EMC to take significant step too, made sure the job of electron beam welder needs. High-pressured welder uses high-pressured power source (150kV) use power source of inversion high pressure, in high pressure interlocking protection respect actors or actress point out is shown, the improvement to character of electron beam spot, welder art increase a respect especially such. Beginning high-pressured welder to use the research of high-pressured power source is the new task of manufacturing industry of welder of our country electron beam, the experience of this power source and the research that design data to use high-pressured power source to high-pressured welder have referenced sense. CNC Milling CNC Machining